Merge pull request #1303 from 0xProject/feature/contracts/optimizedAbiEncoder

Optimized ABI Encoder

41 files changed, 4913 insertions, 1 deletions

diff --git a/packages/ethereum-types/src/index.ts b/packages/ethereum-types/src/index.ts
index eff38711a..9430fdc98 100644
--- a/packages/ethereum-types/src/index.ts
+++ b/packages/ethereum-types/src/index.ts
@@ -283,6 +283,11 @@ export interface RawLogEntry {
 
 export enum SolidityTypes {
     Address = 'address',
+    Bool = 'bool',
+    Bytes = 'bytes',
+    Int = 'int',
+    String = 'string',
+    Tuple = 'tuple',
     Uint256 = 'uint256',
     Uint8 = 'uint8',
     Uint = 'uint',
diff --git a/packages/utils/CHANGELOG.json b/packages/utils/CHANGELOG.json
index 8c6fb124f..08801a891 100644
--- a/packages/utils/CHANGELOG.json
+++ b/packages/utils/CHANGELOG.json
@@ -1,5 +1,15 @@
 [
     {
+        "timestamp": 1543448882,
+        "version": "2.0.7",
+        "changes": [
+            {
+                "note":
+                    "Optimized ABI Encoder/Decoder. Generates compressed calldata to save gas. Generates human-readable calldata to aid development."
+            }
+        ]
+    },
+    {
         "timestamp": 1542821676,
         "version": "2.0.6",
         "changes": [
diff --git a/packages/utils/package.json b/packages/utils/package.json
index 8dc1f0739..1f4d85843 100644
--- a/packages/utils/package.json
+++ b/packages/utils/package.json
@@ -33,6 +33,9 @@
         "@types/lodash": "4.14.104",
         "@types/mocha": "^2.2.42",
         "chai": "^4.0.1",
+        "chai-as-promised": "^7.1.0",
+        "chai-bignumber": "^2.0.1",
+        "dirty-chai": "^2.0.1",
         "make-promises-safe": "^1.1.0",
         "mocha": "^4.1.0",
         "npm-run-all": "^4.1.2",
@@ -57,4 +60,4 @@
     "publishConfig": {
         "access": "public"
     }
-}
+}
\ No newline at end of file
diff --git a/packages/utils/src/abi_encoder/abstract_data_types/data_type.ts b/packages/utils/src/abi_encoder/abstract_data_types/data_type.ts
new file mode 100644
index 000000000..13cc87e2a
--- /dev/null
+++ b/packages/utils/src/abi_encoder/abstract_data_types/data_type.ts
@@ -0,0 +1,58 @@
+import { DataItem } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { Calldata } from '../calldata/calldata';
+import { CalldataBlock } from '../calldata/calldata_block';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+import { DecodingRules, EncodingRules } from '../utils/rules';
+
+import { DataTypeFactory } from './interfaces';
+
+export abstract class DataType {
+    private readonly _dataItem: DataItem;
+    private readonly _factory: DataTypeFactory;
+
+    constructor(dataItem: DataItem, factory: DataTypeFactory) {
+        this._dataItem = dataItem;
+        this._factory = factory;
+    }
+
+    public getDataItem(): DataItem {
+        return this._dataItem;
+    }
+
+    public getFactory(): DataTypeFactory {
+        return this._factory;
+    }
+
+    public encode(value: any, rules?: EncodingRules, selector?: string): string {
+        const rules_ = _.isUndefined(rules) ? constants.DEFAULT_ENCODING_RULES : rules;
+        const calldata = new Calldata(rules_);
+        if (!_.isUndefined(selector)) {
+            calldata.setSelector(selector);
+        }
+        const block = this.generateCalldataBlock(value);
+        calldata.setRoot(block);
+        const encodedCalldata = calldata.toString();
+        return encodedCalldata;
+    }
+
+    public decode(calldata: string, rules?: DecodingRules, selector?: string): any {
+        if (!_.isUndefined(selector) && !_.startsWith(calldata, selector)) {
+            throw new Error(
+                `Tried to decode calldata, but it was missing the function selector. Expected prefix '${selector}'. Got '${calldata}'.`,
+            );
+        }
+        const hasSelector = !_.isUndefined(selector);
+        const rawCalldata = new RawCalldata(calldata, hasSelector);
+        const rules_ = _.isUndefined(rules) ? constants.DEFAULT_DECODING_RULES : rules;
+        const value = this.generateValue(rawCalldata, rules_);
+        return value;
+    }
+
+    public abstract generateCalldataBlock(value: any, parentBlock?: CalldataBlock): CalldataBlock;
+    public abstract generateValue(calldata: RawCalldata, rules: DecodingRules): any;
+    public abstract getSignature(): string;
+    public abstract isStatic(): boolean;
+}
diff --git a/packages/utils/src/abi_encoder/abstract_data_types/interfaces.ts b/packages/utils/src/abi_encoder/abstract_data_types/interfaces.ts
new file mode 100644
index 000000000..2f2f60871
--- /dev/null
+++ b/packages/utils/src/abi_encoder/abstract_data_types/interfaces.ts
@@ -0,0 +1,19 @@
+import { DataItem } from 'ethereum-types';
+
+import { RawCalldata } from '../calldata/raw_calldata';
+
+import { DataType } from './data_type';
+
+export interface DataTypeFactory {
+    create: (dataItem: DataItem, parentDataType?: DataType) => DataType;
+}
+
+export interface DataTypeStaticInterface {
+    matchType: (type: string) => boolean;
+    encodeValue: (value: any) => Buffer;
+    decodeValue: (rawCalldata: RawCalldata) => any;
+}
+
+export interface MemberIndexByName {
+    [key: string]: number;
+}
diff --git a/packages/utils/src/abi_encoder/abstract_data_types/types/blob.ts b/packages/utils/src/abi_encoder/abstract_data_types/types/blob.ts
new file mode 100644
index 000000000..a091e55b9
--- /dev/null
+++ b/packages/utils/src/abi_encoder/abstract_data_types/types/blob.ts
@@ -0,0 +1,40 @@
+import { DataItem } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { BlobCalldataBlock } from '../../calldata/blocks/blob';
+import { CalldataBlock } from '../../calldata/calldata_block';
+import { RawCalldata } from '../../calldata/raw_calldata';
+import { DecodingRules } from '../../utils/rules';
+
+import { DataType } from '../data_type';
+import { DataTypeFactory } from '../interfaces';
+
+export abstract class AbstractBlobDataType extends DataType {
+    protected _sizeKnownAtCompileTime: boolean;
+
+    public constructor(dataItem: DataItem, factory: DataTypeFactory, sizeKnownAtCompileTime: boolean) {
+        super(dataItem, factory);
+        this._sizeKnownAtCompileTime = sizeKnownAtCompileTime;
+    }
+
+    public generateCalldataBlock(value: any, parentBlock?: CalldataBlock): BlobCalldataBlock {
+        const encodedValue = this.encodeValue(value);
+        const name = this.getDataItem().name;
+        const signature = this.getSignature();
+        const parentName = _.isUndefined(parentBlock) ? '' : parentBlock.getName();
+        const block = new BlobCalldataBlock(name, signature, parentName, encodedValue);
+        return block;
+    }
+
+    public generateValue(calldata: RawCalldata, rules: DecodingRules): any {
+        const value = this.decodeValue(calldata);
+        return value;
+    }
+
+    public isStatic(): boolean {
+        return this._sizeKnownAtCompileTime;
+    }
+
+    public abstract encodeValue(value: any): Buffer;
+    public abstract decodeValue(calldata: RawCalldata): any;
+}
diff --git a/packages/utils/src/abi_encoder/abstract_data_types/types/pointer.ts b/packages/utils/src/abi_encoder/abstract_data_types/types/pointer.ts
new file mode 100644
index 000000000..0f3c55280
--- /dev/null
+++ b/packages/utils/src/abi_encoder/abstract_data_types/types/pointer.ts
@@ -0,0 +1,54 @@
+import { DataItem } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { PointerCalldataBlock } from '../../calldata/blocks/pointer';
+import { CalldataBlock } from '../../calldata/calldata_block';
+import { RawCalldata } from '../../calldata/raw_calldata';
+import { constants } from '../../utils/constants';
+import { DecodingRules } from '../../utils/rules';
+
+import { DataType } from '../data_type';
+import { DataTypeFactory } from '../interfaces';
+
+export abstract class AbstractPointerDataType extends DataType {
+    protected _destination: DataType;
+    protected _parent: DataType;
+
+    public constructor(dataItem: DataItem, factory: DataTypeFactory, destination: DataType, parent: DataType) {
+        super(dataItem, factory);
+        this._destination = destination;
+        this._parent = parent;
+    }
+
+    public generateCalldataBlock(value: any, parentBlock?: CalldataBlock): PointerCalldataBlock {
+        if (_.isUndefined(parentBlock)) {
+            throw new Error(`DependentDataType requires a parent block to generate its block`);
+        }
+        const destinationBlock = this._destination.generateCalldataBlock(value, parentBlock);
+        const name = this.getDataItem().name;
+        const signature = this.getSignature();
+        const parentName = parentBlock.getName();
+        const block = new PointerCalldataBlock(name, signature, parentName, destinationBlock, parentBlock);
+        return block;
+    }
+
+    public generateValue(calldata: RawCalldata, rules: DecodingRules): any {
+        const destinationOffsetBuf = calldata.popWord();
+        const destinationOffsetHex = ethUtil.bufferToHex(destinationOffsetBuf);
+        const destinationOffsetRelative = parseInt(destinationOffsetHex, constants.HEX_BASE);
+        const destinationOffsetAbsolute = calldata.toAbsoluteOffset(destinationOffsetRelative);
+        const currentOffset = calldata.getOffset();
+        calldata.setOffset(destinationOffsetAbsolute);
+        const value = this._destination.generateValue(calldata, rules);
+        calldata.setOffset(currentOffset);
+        return value;
+    }
+
+    // Disable prefer-function-over-method for inherited abstract method.
+    /* tslint:disable prefer-function-over-method */
+    public isStatic(): boolean {
+        return true;
+    }
+    /* tslint:enable prefer-function-over-method */
+}
diff --git a/packages/utils/src/abi_encoder/abstract_data_types/types/set.ts b/packages/utils/src/abi_encoder/abstract_data_types/types/set.ts
new file mode 100644
index 000000000..089d04659
--- /dev/null
+++ b/packages/utils/src/abi_encoder/abstract_data_types/types/set.ts
@@ -0,0 +1,218 @@
+import { DataItem } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { BigNumber } from '../../../configured_bignumber';
+import { SetCalldataBlock } from '../../calldata/blocks/set';
+import { CalldataBlock } from '../../calldata/calldata_block';
+import { RawCalldata } from '../../calldata/raw_calldata';
+import { constants } from '../../utils/constants';
+import { DecodingRules } from '../../utils/rules';
+
+import { DataType } from '../data_type';
+import { DataTypeFactory, MemberIndexByName } from '../interfaces';
+
+import { AbstractPointerDataType } from './pointer';
+
+export abstract class AbstractSetDataType extends DataType {
+    protected readonly _arrayLength: number | undefined;
+    protected readonly _arrayElementType: string | undefined;
+    private readonly _memberIndexByName: MemberIndexByName;
+    private readonly _members: DataType[];
+    private readonly _isArray: boolean;
+
+    public constructor(
+        dataItem: DataItem,
+        factory: DataTypeFactory,
+        isArray: boolean = false,
+        arrayLength?: number,
+        arrayElementType?: string,
+    ) {
+        super(dataItem, factory);
+        this._memberIndexByName = {};
+        this._members = [];
+        this._isArray = isArray;
+        this._arrayLength = arrayLength;
+        this._arrayElementType = arrayElementType;
+        if (isArray && !_.isUndefined(arrayLength)) {
+            [this._members, this._memberIndexByName] = this._createMembersWithLength(dataItem, arrayLength);
+        } else if (!isArray) {
+            [this._members, this._memberIndexByName] = this._createMembersWithKeys(dataItem);
+        }
+    }
+
+    public generateCalldataBlock(value: any[] | object, parentBlock?: CalldataBlock): SetCalldataBlock {
+        const block =
+            value instanceof Array
+                ? this._generateCalldataBlockFromArray(value, parentBlock)
+                : this._generateCalldataBlockFromObject(value, parentBlock);
+        return block;
+    }
+
+    public generateValue(calldata: RawCalldata, rules: DecodingRules): any[] | object {
+        let members = this._members;
+        // Case 1: This is an array of undefined length, which means that `this._members` was not
+        //         populated in the constructor. So we must construct the set of members now.
+        if (this._isArray && _.isUndefined(this._arrayLength)) {
+            const arrayLengthBuf = calldata.popWord();
+            const arrayLengthHex = ethUtil.bufferToHex(arrayLengthBuf);
+            const arrayLength = new BigNumber(arrayLengthHex, constants.HEX_BASE);
+            [members] = this._createMembersWithLength(this.getDataItem(), arrayLength.toNumber());
+        }
+        // Create a new scope in the calldata, before descending into the members of this set.
+        calldata.startScope();
+        let value: any[] | object;
+        if (rules.structsAsObjects && !this._isArray) {
+            // Construct an object with values for each member of the set.
+            value = {};
+            _.each(this._memberIndexByName, (idx: number, key: string) => {
+                const member = this._members[idx];
+                const memberValue = member.generateValue(calldata, rules);
+                (value as { [key: string]: any })[key] = memberValue;
+            });
+        } else {
+            // Construct an array with values for each member of the set.
+            value = [];
+            _.each(members, (member: DataType, idx: number) => {
+                const memberValue = member.generateValue(calldata, rules);
+                (value as any[]).push(memberValue);
+            });
+        }
+        // Close this scope and return tetheh value.
+        calldata.endScope();
+        return value;
+    }
+
+    public isStatic(): boolean {
+        // An array with an undefined length is never static.
+        if (this._isArray && _.isUndefined(this._arrayLength)) {
+            return false;
+        }
+        // If any member of the set is a pointer then the set is not static.
+        const dependentMember = _.find(this._members, (member: DataType) => {
+            return member instanceof AbstractPointerDataType;
+        });
+        const isStatic = _.isUndefined(dependentMember);
+        return isStatic;
+    }
+
+    protected _generateCalldataBlockFromArray(value: any[], parentBlock?: CalldataBlock): SetCalldataBlock {
+        // Sanity check: if the set has a defined length then `value` must have the same length.
+        if (!_.isUndefined(this._arrayLength) && value.length !== this._arrayLength) {
+            throw new Error(
+                `Expected array of ${JSON.stringify(
+                    this._arrayLength,
+                )} elements, but got array of length ${JSON.stringify(value.length)}`,
+            );
+        }
+        // Create a new calldata block for this set.
+        const parentName = _.isUndefined(parentBlock) ? '' : parentBlock.getName();
+        const block = new SetCalldataBlock(this.getDataItem().name, this.getSignature(), parentName);
+        // If this set has an undefined length then set its header to be the number of elements.
+        let members = this._members;
+        if (this._isArray && _.isUndefined(this._arrayLength)) {
+            [members] = this._createMembersWithLength(this.getDataItem(), value.length);
+            const lenBuf = ethUtil.setLengthLeft(
+                ethUtil.toBuffer(`0x${value.length.toString(constants.HEX_BASE)}`),
+                constants.EVM_WORD_WIDTH_IN_BYTES,
+            );
+            block.setHeader(lenBuf);
+        }
+        // Create blocks for members of set.
+        const memberCalldataBlocks: CalldataBlock[] = [];
+        _.each(members, (member: DataType, idx: number) => {
+            const memberBlock = member.generateCalldataBlock(value[idx], block);
+            memberCalldataBlocks.push(memberBlock);
+        });
+        block.setMembers(memberCalldataBlocks);
+        return block;
+    }
+
+    protected _generateCalldataBlockFromObject(obj: object, parentBlock?: CalldataBlock): SetCalldataBlock {
+        // Create a new calldata block for this set.
+        const parentName = _.isUndefined(parentBlock) ? '' : parentBlock.getName();
+        const block = new SetCalldataBlock(this.getDataItem().name, this.getSignature(), parentName);
+        // Create blocks for members of set.
+        const memberCalldataBlocks: CalldataBlock[] = [];
+        const childMap = _.cloneDeep(this._memberIndexByName);
+        _.forOwn(obj, (value: any, key: string) => {
+            if (!(key in childMap)) {
+                throw new Error(
+                    `Could not assign tuple to object: unrecognized key '${key}' in object ${this.getDataItem().name}`,
+                );
+            }
+            const memberBlock = this._members[this._memberIndexByName[key]].generateCalldataBlock(value, block);
+            memberCalldataBlocks.push(memberBlock);
+            delete childMap[key];
+        });
+        // Sanity check that all members have been included.
+        if (Object.keys(childMap).length !== 0) {
+            throw new Error(`Could not assign tuple to object: missing keys ${Object.keys(childMap)}`);
+        }
+        // Associate member blocks with Set block.
+        block.setMembers(memberCalldataBlocks);
+        return block;
+    }
+
+    protected _computeSignatureOfMembers(): string {
+        // Compute signature of members
+        let signature = `(`;
+        _.each(this._members, (member: DataType, i: number) => {
+            signature += member.getSignature();
+            if (i < this._members.length - 1) {
+                signature += ',';
+            }
+        });
+        signature += ')';
+        return signature;
+    }
+
+    private _createMembersWithKeys(dataItem: DataItem): [DataType[], MemberIndexByName] {
+        // Sanity check
+        if (_.isUndefined(dataItem.components)) {
+            throw new Error(
+                `Tried to create a set using key/value pairs, but no components were defined by the input DataItem '${
+                    dataItem.name
+                }'.`,
+            );
+        }
+        // Create one member for each component of `dataItem`
+        const members: DataType[] = [];
+        const memberIndexByName: MemberIndexByName = {};
+        _.each(dataItem.components, (memberItem: DataItem) => {
+            const childDataItem: DataItem = {
+                type: memberItem.type,
+                name: `${dataItem.name}.${memberItem.name}`,
+            };
+            const components = memberItem.components;
+            if (!_.isUndefined(components)) {
+                childDataItem.components = components;
+            }
+            const child = this.getFactory().create(childDataItem, this);
+            memberIndexByName[memberItem.name] = members.length;
+            members.push(child);
+        });
+        return [members, memberIndexByName];
+    }
+
+    private _createMembersWithLength(dataItem: DataItem, length: number): [DataType[], MemberIndexByName] {
+        // Create `length` members, deriving the type from `dataItem`
+        const members: DataType[] = [];
+        const memberIndexByName: MemberIndexByName = {};
+        const range = _.range(length);
+        _.each(range, (idx: number) => {
+            const memberDataItem: DataItem = {
+                type: _.isUndefined(this._arrayElementType) ? '' : this._arrayElementType,
+                name: `${dataItem.name}[${idx.toString(constants.DEC_BASE)}]`,
+            };
+            const components = dataItem.components;
+            if (!_.isUndefined(components)) {
+                memberDataItem.components = components;
+            }
+            const memberType = this.getFactory().create(memberDataItem, this);
+            memberIndexByName[idx.toString(constants.DEC_BASE)] = members.length;
+            members.push(memberType);
+        });
+        return [members, memberIndexByName];
+    }
+}
diff --git a/packages/utils/src/abi_encoder/calldata/blocks/blob.ts b/packages/utils/src/abi_encoder/calldata/blocks/blob.ts
new file mode 100644
index 000000000..219ea6c61
--- /dev/null
+++ b/packages/utils/src/abi_encoder/calldata/blocks/blob.ts
@@ -0,0 +1,20 @@
+import { CalldataBlock } from '../calldata_block';
+
+export class BlobCalldataBlock extends CalldataBlock {
+    private readonly _blob: Buffer;
+
+    constructor(name: string, signature: string, parentName: string, blob: Buffer) {
+        const headerSizeInBytes = 0;
+        const bodySizeInBytes = blob.byteLength;
+        super(name, signature, parentName, headerSizeInBytes, bodySizeInBytes);
+        this._blob = blob;
+    }
+
+    public toBuffer(): Buffer {
+        return this._blob;
+    }
+
+    public getRawData(): Buffer {
+        return this._blob;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/calldata/blocks/pointer.ts b/packages/utils/src/abi_encoder/calldata/blocks/pointer.ts
new file mode 100644
index 000000000..72d6a3173
--- /dev/null
+++ b/packages/utils/src/abi_encoder/calldata/blocks/pointer.ts
@@ -0,0 +1,61 @@
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { constants } from '../../utils/constants';
+
+import { CalldataBlock } from '../calldata_block';
+
+export class PointerCalldataBlock extends CalldataBlock {
+    public static readonly RAW_DATA_START = new Buffer('<');
+    public static readonly RAW_DATA_END = new Buffer('>');
+    private static readonly _DEPENDENT_PAYLOAD_SIZE_IN_BYTES = 32;
+    private static readonly _EMPTY_HEADER_SIZE = 0;
+    private readonly _parent: CalldataBlock;
+    private readonly _dependency: CalldataBlock;
+    private _aliasFor: CalldataBlock | undefined;
+
+    constructor(name: string, signature: string, parentName: string, dependency: CalldataBlock, parent: CalldataBlock) {
+        const headerSizeInBytes = PointerCalldataBlock._EMPTY_HEADER_SIZE;
+        const bodySizeInBytes = PointerCalldataBlock._DEPENDENT_PAYLOAD_SIZE_IN_BYTES;
+        super(name, signature, parentName, headerSizeInBytes, bodySizeInBytes);
+        this._parent = parent;
+        this._dependency = dependency;
+        this._aliasFor = undefined;
+    }
+
+    public toBuffer(): Buffer {
+        const destinationOffset = !_.isUndefined(this._aliasFor)
+            ? this._aliasFor.getOffsetInBytes()
+            : this._dependency.getOffsetInBytes();
+        const parentOffset = this._parent.getOffsetInBytes();
+        const parentHeaderSize = this._parent.getHeaderSizeInBytes();
+        const pointer: number = destinationOffset - (parentOffset + parentHeaderSize);
+        const pointerHex = `0x${pointer.toString(constants.HEX_BASE)}`;
+        const pointerBuf = ethUtil.toBuffer(pointerHex);
+        const pointerBufPadded = ethUtil.setLengthLeft(pointerBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
+        return pointerBufPadded;
+    }
+
+    public getDependency(): CalldataBlock {
+        return this._dependency;
+    }
+
+    public setAlias(block: CalldataBlock): void {
+        this._aliasFor = block;
+        this._setName(`${this.getName()} (alias for ${block.getName()})`);
+    }
+
+    public getAlias(): CalldataBlock | undefined {
+        return this._aliasFor;
+    }
+
+    public getRawData(): Buffer {
+        const dependencyRawData = this._dependency.getRawData();
+        const rawDataComponents: Buffer[] = [];
+        rawDataComponents.push(PointerCalldataBlock.RAW_DATA_START);
+        rawDataComponents.push(dependencyRawData);
+        rawDataComponents.push(PointerCalldataBlock.RAW_DATA_END);
+        const rawData = Buffer.concat(rawDataComponents);
+        return rawData;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/calldata/blocks/set.ts b/packages/utils/src/abi_encoder/calldata/blocks/set.ts
new file mode 100644
index 000000000..d1abc4986
--- /dev/null
+++ b/packages/utils/src/abi_encoder/calldata/blocks/set.ts
@@ -0,0 +1,47 @@
+import * as _ from 'lodash';
+
+import { CalldataBlock } from '../calldata_block';
+
+export class SetCalldataBlock extends CalldataBlock {
+    private _header: Buffer | undefined;
+    private _members: CalldataBlock[];
+
+    constructor(name: string, signature: string, parentName: string) {
+        super(name, signature, parentName, 0, 0);
+        this._members = [];
+        this._header = undefined;
+    }
+
+    public getRawData(): Buffer {
+        const rawDataComponents: Buffer[] = [];
+        if (!_.isUndefined(this._header)) {
+            rawDataComponents.push(this._header);
+        }
+        _.each(this._members, (member: CalldataBlock) => {
+            const memberBuffer = member.getRawData();
+            rawDataComponents.push(memberBuffer);
+        });
+        const rawData = Buffer.concat(rawDataComponents);
+        return rawData;
+    }
+
+    public setMembers(members: CalldataBlock[]): void {
+        this._members = members;
+    }
+
+    public setHeader(header: Buffer): void {
+        this._setHeaderSize(header.byteLength);
+        this._header = header;
+    }
+
+    public toBuffer(): Buffer {
+        if (!_.isUndefined(this._header)) {
+            return this._header;
+        }
+        return new Buffer('');
+    }
+
+    public getMembers(): CalldataBlock[] {
+        return this._members;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/calldata/calldata.ts b/packages/utils/src/abi_encoder/calldata/calldata.ts
new file mode 100644
index 000000000..5f3eee94a
--- /dev/null
+++ b/packages/utils/src/abi_encoder/calldata/calldata.ts
@@ -0,0 +1,243 @@
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { constants } from '../utils/constants';
+import { EncodingRules } from '../utils/rules';
+
+import { PointerCalldataBlock } from './blocks/pointer';
+import { SetCalldataBlock } from './blocks/set';
+import { CalldataBlock } from './calldata_block';
+import { CalldataIterator, ReverseCalldataIterator } from './iterator';
+
+export class Calldata {
+    private readonly _rules: EncodingRules;
+    private _selector: string;
+    private _root: CalldataBlock | undefined;
+
+    public constructor(rules: EncodingRules) {
+        this._rules = rules;
+        this._selector = '';
+        this._root = undefined;
+    }
+    /**
+     * Sets the root calldata block. This block usually corresponds to a Method.
+     */
+    public setRoot(block: CalldataBlock): void {
+        this._root = block;
+    }
+    /**
+     * Sets the selector to be prepended onto the calldata.
+     * If the root block was created by a Method then a selector will likely be set.
+     */
+    public setSelector(selector: string): void {
+        if (!_.startsWith(selector, '0x')) {
+            throw new Error(`Expected selector to be hex. Missing prefix '0x'`);
+        } else if (selector.length !== constants.HEX_SELECTOR_LENGTH_IN_CHARS) {
+            throw new Error(`Invalid selector '${selector}'`);
+        }
+        this._selector = selector;
+    }
+    /**
+     * Iterates through the calldata blocks, starting from the root block, to construct calldata as a hex string.
+     * If the `optimize` flag is set then this calldata will be condensed, to save gas.
+     * If the `annotate` flag is set then this will return human-readable calldata.
+     * If the `annotate` flag is *not* set then this will return EVM-compatible calldata.
+     */
+    public toString(): string {
+        // Sanity check: root block must be set
+        if (_.isUndefined(this._root)) {
+            throw new Error('expected root');
+        }
+        // Optimize, if flag set
+        if (this._rules.optimize) {
+            this._optimize();
+        }
+        // Set offsets
+        const iterator = new CalldataIterator(this._root);
+        let offset = 0;
+        for (const block of iterator) {
+            block.setOffset(offset);
+            offset += block.getSizeInBytes();
+        }
+        // Generate hex string
+        const hexString = this._rules.annotate ? this._toHumanReadableCallData() : this._toEvmCompatibeCallDataHex();
+        return hexString;
+    }
+    /**
+     * There are three types of calldata blocks: Blob, Set and Pointer.
+     * Scenarios arise where distinct pointers resolve to identical values.
+     * We optimize by keeping only one such instance of the identical value, and redirecting all pointers here.
+     * We keep the last such duplicate value because pointers can only be positive (they cannot point backwards).
+     *
+     * Example #1:
+     *  function f(string[], string[])
+     *  f(["foo", "bar", "blitz"], ["foo", "bar", "blitz"])
+     *  The array ["foo", "bar", "blitz"] will only be included in the calldata once.
+     *
+     * Example #2:
+     *  function f(string[], string)
+     *  f(["foo", "bar", "blitz"], "foo")
+     *  The string "foo" will only be included in the calldata once.
+     *
+     * Example #3:
+     *  function f((string, uint, bytes), string, uint, bytes)
+     *  f(("foo", 5, "0x05"), "foo", 5, "0x05")
+     *  The string "foo" and bytes "0x05" will only be included in the calldata once.
+     *  The duplicate `uint 5` values cannot be optimized out because they are static values (no pointer points to them).
+     *
+     * @TODO #1:
+     *   This optimization strategy handles blocks that are exact duplicates of one another.
+     *   But what if some block is a combination of two other blocks? Or a subset of another block?
+     *   This optimization problem is not much different from the current implemetation.
+     *   Instead of tracking "observed" hashes, at each node we would simply do pattern-matching on the calldata.
+     *   This strategy would be applied after assigning offsets to the tree, rather than before (as in this strategy).
+     *   Note that one consequence of this strategy is pointers may resolve to offsets that are not word-aligned.
+     *   This shouldn't be a problem but further investigation should be done.
+     *
+     * @TODO #2:
+     *   To be done as a follow-up to @TODO #1.
+     *   Since we optimize from the bottom-up, we could be affecting the outcome of a later potential optimization.
+     *   For example, what if by removing one duplicate value we miss out on optimizing another block higher in the tree.
+     *   To handle this case, at each node we can store a candidate optimization in a priority queue (sorted by calldata size).
+     *   At the end of traversing the tree, the candidate at the front of the queue will be the most optimal output.
+     *
+     */
+    private _optimize(): void {
+        // Step 1/1 Create a reverse iterator (starts from the end of the calldata to the beginning)
+        if (_.isUndefined(this._root)) {
+            throw new Error('expected root');
+        }
+        const iterator = new ReverseCalldataIterator(this._root);
+        // Step 2/2 Iterate over each block, keeping track of which blocks have been seen and pruning redundant blocks.
+        const blocksByHash: { [key: string]: CalldataBlock } = {};
+        for (const block of iterator) {
+            // If a block is a pointer and its value has already been observed, then update
+            // the pointer to resolve to the existing value.
+            if (block instanceof PointerCalldataBlock) {
+                const dependencyBlockHashBuf = block.getDependency().computeHash();
+                const dependencyBlockHash = ethUtil.bufferToHex(dependencyBlockHashBuf);
+                if (dependencyBlockHash in blocksByHash) {
+                    const blockWithSameHash = blocksByHash[dependencyBlockHash];
+                    if (blockWithSameHash !== block.getDependency()) {
+                        block.setAlias(blockWithSameHash);
+                    }
+                }
+                continue;
+            }
+            // This block has not been seen. Record its hash.
+            const blockHashBuf = block.computeHash();
+            const blockHash = ethUtil.bufferToHex(blockHashBuf);
+            if (!(blockHash in blocksByHash)) {
+                blocksByHash[blockHash] = block;
+            }
+        }
+    }
+    private _toEvmCompatibeCallDataHex(): string {
+        // Sanity check: must have a root block.
+        if (_.isUndefined(this._root)) {
+            throw new Error('expected root');
+        }
+        // Construct an array of buffers (one buffer for each block).
+        const selectorBuffer = ethUtil.toBuffer(this._selector);
+        const valueBufs: Buffer[] = [selectorBuffer];
+        const iterator = new CalldataIterator(this._root);
+        for (const block of iterator) {
+            valueBufs.push(block.toBuffer());
+        }
+        // Create hex from buffer array.
+        const combinedBuffers = Buffer.concat(valueBufs);
+        const hexValue = ethUtil.bufferToHex(combinedBuffers);
+        return hexValue;
+    }
+    /**
+     * Returns human-readable calldata.
+     *
+     * Example:
+     *   simpleFunction(string[], string[])
+     *   strings = ["Hello", "World"]
+     *   simpleFunction(strings, strings)
+     *
+     * Output:
+     *   0xbb4f12e3
+     *                                                                                      ### simpleFunction
+     *   0x0       0000000000000000000000000000000000000000000000000000000000000040              ptr<array1> (alias for array2)
+     *   0x20      0000000000000000000000000000000000000000000000000000000000000040              ptr<array2>
+     *
+     *   0x40      0000000000000000000000000000000000000000000000000000000000000002          ### array2
+     *   0x60      0000000000000000000000000000000000000000000000000000000000000040              ptr<array2[0]>
+     *   0x80      0000000000000000000000000000000000000000000000000000000000000080              ptr<array2[1]>
+     *   0xa0      0000000000000000000000000000000000000000000000000000000000000005              array2[0]
+     *   0xc0      48656c6c6f000000000000000000000000000000000000000000000000000000
+     *   0xe0      0000000000000000000000000000000000000000000000000000000000000005              array2[1]
+     *   0x100     576f726c64000000000000000000000000000000000000000000000000000000
+     */
+    private _toHumanReadableCallData(): string {
+        // Sanity check: must have a root block.
+        if (_.isUndefined(this._root)) {
+            throw new Error('expected root');
+        }
+        // Constants for constructing annotated string
+        const offsetPadding = 10;
+        const valuePadding = 74;
+        const namePadding = 80;
+        const evmWordStartIndex = 0;
+        const emptySize = 0;
+        // Construct annotated calldata
+        let hexValue = `${this._selector}`;
+        let offset = 0;
+        const functionName: string = this._root.getName();
+        const iterator = new CalldataIterator(this._root);
+        for (const block of iterator) {
+            // Process each block 1 word at a time
+            const size = block.getSizeInBytes();
+            const name = block.getName();
+            const parentName = block.getParentName();
+            const prettyName = name.replace(`${parentName}.`, '').replace(`${functionName}.`, '');
+            // Resulting line will be <offsetStr><valueStr><nameStr>
+            let offsetStr = '';
+            let valueStr = '';
+            let nameStr = '';
+            let lineStr = '';
+            if (size === emptySize) {
+                // This is a Set block with no header.
+                // For example, a tuple or an array with a defined length.
+                offsetStr = ' '.repeat(offsetPadding);
+                valueStr = ' '.repeat(valuePadding);
+                nameStr = `### ${prettyName.padEnd(namePadding)}`;
+                lineStr = `\n${offsetStr}${valueStr}${nameStr}`;
+            } else {
+                // This block has at least one word of value.
+                offsetStr = `0x${offset.toString(constants.HEX_BASE)}`.padEnd(offsetPadding);
+                valueStr = ethUtil
+                    .stripHexPrefix(
+                        ethUtil.bufferToHex(
+                            block.toBuffer().slice(evmWordStartIndex, constants.EVM_WORD_WIDTH_IN_BYTES),
+                        ),
+                    )
+                    .padEnd(valuePadding);
+                if (block instanceof SetCalldataBlock) {
+                    nameStr = `### ${prettyName.padEnd(namePadding)}`;
+                    lineStr = `\n${offsetStr}${valueStr}${nameStr}`;
+                } else {
+                    nameStr = `    ${prettyName.padEnd(namePadding)}`;
+                    lineStr = `${offsetStr}${valueStr}${nameStr}`;
+                }
+            }
+            // This block has a value that is more than 1 word.
+            for (let j = constants.EVM_WORD_WIDTH_IN_BYTES; j < size; j += constants.EVM_WORD_WIDTH_IN_BYTES) {
+                offsetStr = `0x${(offset + j).toString(constants.HEX_BASE)}`.padEnd(offsetPadding);
+                valueStr = ethUtil
+                    .stripHexPrefix(
+                        ethUtil.bufferToHex(block.toBuffer().slice(j, j + constants.EVM_WORD_WIDTH_IN_BYTES)),
+                    )
+                    .padEnd(valuePadding);
+                nameStr = ' '.repeat(namePadding);
+                lineStr = `${lineStr}\n${offsetStr}${valueStr}${nameStr}`;
+            }
+            // Append to hex value
+            hexValue = `${hexValue}\n${lineStr}`;
+            offset += size;
+        }
+        return hexValue;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/calldata/calldata_block.ts b/packages/utils/src/abi_encoder/calldata/calldata_block.ts
new file mode 100644
index 000000000..35bd994e5
--- /dev/null
+++ b/packages/utils/src/abi_encoder/calldata/calldata_block.ts
@@ -0,0 +1,77 @@
+import * as ethUtil from 'ethereumjs-util';
+
+export abstract class CalldataBlock {
+    private readonly _signature: string;
+    private readonly _parentName: string;
+    private _name: string;
+    private _offsetInBytes: number;
+    private _headerSizeInBytes: number;
+    private _bodySizeInBytes: number;
+
+    constructor(
+        name: string,
+        signature: string,
+        parentName: string,
+        headerSizeInBytes: number,
+        bodySizeInBytes: number,
+    ) {
+        this._name = name;
+        this._signature = signature;
+        this._parentName = parentName;
+        this._offsetInBytes = 0;
+        this._headerSizeInBytes = headerSizeInBytes;
+        this._bodySizeInBytes = bodySizeInBytes;
+    }
+
+    protected _setHeaderSize(headerSizeInBytes: number): void {
+        this._headerSizeInBytes = headerSizeInBytes;
+    }
+
+    protected _setBodySize(bodySizeInBytes: number): void {
+        this._bodySizeInBytes = bodySizeInBytes;
+    }
+
+    protected _setName(name: string): void {
+        this._name = name;
+    }
+
+    public getName(): string {
+        return this._name;
+    }
+
+    public getParentName(): string {
+        return this._parentName;
+    }
+
+    public getSignature(): string {
+        return this._signature;
+    }
+    public getHeaderSizeInBytes(): number {
+        return this._headerSizeInBytes;
+    }
+
+    public getBodySizeInBytes(): number {
+        return this._bodySizeInBytes;
+    }
+
+    public getSizeInBytes(): number {
+        return this.getHeaderSizeInBytes() + this.getBodySizeInBytes();
+    }
+
+    public getOffsetInBytes(): number {
+        return this._offsetInBytes;
+    }
+
+    public setOffset(offsetInBytes: number): void {
+        this._offsetInBytes = offsetInBytes;
+    }
+
+    public computeHash(): Buffer {
+        const rawData = this.getRawData();
+        const hash = ethUtil.sha3(rawData);
+        return hash;
+    }
+
+    public abstract toBuffer(): Buffer;
+    public abstract getRawData(): Buffer;
+}
diff --git a/packages/utils/src/abi_encoder/calldata/iterator.ts b/packages/utils/src/abi_encoder/calldata/iterator.ts
new file mode 100644
index 000000000..333b32b4f
--- /dev/null
+++ b/packages/utils/src/abi_encoder/calldata/iterator.ts
@@ -0,0 +1,114 @@
+/* tslint:disable max-classes-per-file */
+import * as _ from 'lodash';
+
+import { Queue } from '../utils/queue';
+
+import { BlobCalldataBlock } from './blocks/blob';
+import { PointerCalldataBlock } from './blocks/pointer';
+import { SetCalldataBlock } from './blocks/set';
+import { CalldataBlock } from './calldata_block';
+
+/**
+ * Iterator class for Calldata Blocks. Blocks follows the order
+ * they should be put into calldata that is passed to he EVM.
+ *
+ * Example #1:
+ * Let root = Set {
+ *                  Blob{} A,
+ *                  Pointer {
+ *                      Blob{} a
+ *                  } B,
+ *                  Blob{} C
+ *            }
+ * It will iterate as follows: [A, B, C, B.a]
+ *
+ * Example #2:
+ * Let root = Set {
+ *                  Blob{} A,
+ *                  Pointer {
+ *                      Blob{} a
+ *                      Pointer {
+ *                          Blob{} b
+ *                      }
+ *                  } B,
+ *                  Pointer {
+ *                      Blob{} c
+ *                  } C
+ *            }
+ * It will iterate as follows: [A, B, C, B.a, B.b, C.c]
+ */
+abstract class BaseIterator implements Iterable<CalldataBlock> {
+    protected readonly _root: CalldataBlock;
+    protected readonly _queue: Queue<CalldataBlock>;
+
+    private static _createQueue(block: CalldataBlock): Queue<CalldataBlock> {
+        const queue = new Queue<CalldataBlock>();
+        // Base case
+        if (!(block instanceof SetCalldataBlock)) {
+            queue.pushBack(block);
+            return queue;
+        }
+        // This is a set; add members
+        const set = block;
+        _.eachRight(set.getMembers(), (member: CalldataBlock) => {
+            queue.mergeFront(BaseIterator._createQueue(member));
+        });
+        // Add children
+        _.each(set.getMembers(), (member: CalldataBlock) => {
+            // Traverse child if it is a unique pointer.
+            // A pointer that is an alias for another pointer is ignored.
+            if (member instanceof PointerCalldataBlock && _.isUndefined(member.getAlias())) {
+                const dependency = member.getDependency();
+                queue.mergeBack(BaseIterator._createQueue(dependency));
+            }
+        });
+        // Put set block at the front of the queue
+        queue.pushFront(set);
+        return queue;
+    }
+
+    public constructor(root: CalldataBlock) {
+        this._root = root;
+        this._queue = BaseIterator._createQueue(root);
+    }
+
+    public [Symbol.iterator](): { next: () => IteratorResult<CalldataBlock> } {
+        return {
+            next: () => {
+                const nextBlock = this.nextBlock();
+                if (!_.isUndefined(nextBlock)) {
+                    return {
+                        value: nextBlock,
+                        done: false,
+                    };
+                }
+                return {
+                    done: true,
+                    value: new BlobCalldataBlock('', '', '', new Buffer('')),
+                };
+            },
+        };
+    }
+
+    public abstract nextBlock(): CalldataBlock | undefined;
+}
+
+export class CalldataIterator extends BaseIterator {
+    public constructor(root: CalldataBlock) {
+        super(root);
+    }
+
+    public nextBlock(): CalldataBlock | undefined {
+        return this._queue.popFront();
+    }
+}
+
+export class ReverseCalldataIterator extends BaseIterator {
+    public constructor(root: CalldataBlock) {
+        super(root);
+    }
+
+    public nextBlock(): CalldataBlock | undefined {
+        return this._queue.popBack();
+    }
+}
diff --git a/packages/utils/src/abi_encoder/calldata/raw_calldata.ts b/packages/utils/src/abi_encoder/calldata/raw_calldata.ts
new file mode 100644
index 000000000..189841989
--- /dev/null
+++ b/packages/utils/src/abi_encoder/calldata/raw_calldata.ts
@@ -0,0 +1,82 @@
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { constants } from '../utils/constants';
+import { Queue } from '../utils/queue';
+
+export class RawCalldata {
+    private static readonly _INITIAL_OFFSET = 0;
+    private readonly _value: Buffer;
+    private readonly _selector: string;
+    private readonly _scopes: Queue<number>;
+    private _offset: number;
+
+    public constructor(value: string | Buffer, hasSelector: boolean = true) {
+        // Sanity check
+        if (typeof value === 'string' && !_.startsWith(value, '0x')) {
+            throw new Error(`Expected raw calldata to start with '0x'`);
+        }
+        // Construct initial values
+        this._value = ethUtil.toBuffer(value);
+        this._selector = '0x';
+        this._scopes = new Queue<number>();
+        this._scopes.pushBack(RawCalldata._INITIAL_OFFSET);
+        this._offset = RawCalldata._INITIAL_OFFSET;
+        // If there's a selector then slice it
+        if (hasSelector) {
+            const selectorBuf = this._value.slice(constants.HEX_SELECTOR_LENGTH_IN_BYTES);
+            this._value = this._value.slice(constants.HEX_SELECTOR_LENGTH_IN_BYTES);
+            this._selector = ethUtil.bufferToHex(selectorBuf);
+        }
+    }
+
+    public popBytes(lengthInBytes: number): Buffer {
+        const value = this._value.slice(this._offset, this._offset + lengthInBytes);
+        this.setOffset(this._offset + lengthInBytes);
+        return value;
+    }
+
+    public popWord(): Buffer {
+        const wordInBytes = 32;
+        return this.popBytes(wordInBytes);
+    }
+
+    public popWords(length: number): Buffer {
+        const wordInBytes = 32;
+        return this.popBytes(length * wordInBytes);
+    }
+
+    public readBytes(from: number, to: number): Buffer {
+        const value = this._value.slice(from, to);
+        return value;
+    }
+
+    public setOffset(offsetInBytes: number): void {
+        this._offset = offsetInBytes;
+    }
+
+    public startScope(): void {
+        this._scopes.pushFront(this._offset);
+    }
+
+    public endScope(): void {
+        this._scopes.popFront();
+    }
+
+    public getOffset(): number {
+        return this._offset;
+    }
+
+    public toAbsoluteOffset(relativeOffset: number): number {
+        const scopeOffset = this._scopes.peekFront();
+        if (_.isUndefined(scopeOffset)) {
+            throw new Error(`Tried to access undefined scope.`);
+        }
+        const absoluteOffset = relativeOffset + scopeOffset;
+        return absoluteOffset;
+    }
+
+    public getSelector(): string {
+        return this._selector;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_type_factory.ts b/packages/utils/src/abi_encoder/evm_data_type_factory.ts
new file mode 100644
index 000000000..4cc124e0a
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_type_factory.ts
@@ -0,0 +1,132 @@
+/* tslint:disable max-classes-per-file */
+import { DataItem, MethodAbi } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { DataType } from './abstract_data_types/data_type';
+import { DataTypeFactory } from './abstract_data_types/interfaces';
+import { AddressDataType } from './evm_data_types/address';
+import { ArrayDataType } from './evm_data_types/array';
+import { BoolDataType } from './evm_data_types/bool';
+import { DynamicBytesDataType } from './evm_data_types/dynamic_bytes';
+import { IntDataType } from './evm_data_types/int';
+import { MethodDataType } from './evm_data_types/method';
+import { PointerDataType } from './evm_data_types/pointer';
+import { StaticBytesDataType } from './evm_data_types/static_bytes';
+import { StringDataType } from './evm_data_types/string';
+import { TupleDataType } from './evm_data_types/tuple';
+import { UIntDataType } from './evm_data_types/uint';
+
+export class Address extends AddressDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class Bool extends BoolDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class Int extends IntDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class UInt extends UIntDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class StaticBytes extends StaticBytesDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class DynamicBytes extends DynamicBytesDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class String extends StringDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class Pointer extends PointerDataType {
+    public constructor(destDataType: DataType, parentDataType: DataType) {
+        super(destDataType, parentDataType, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class Tuple extends TupleDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class Array extends ArrayDataType {
+    public constructor(dataItem: DataItem) {
+        super(dataItem, EvmDataTypeFactory.getInstance());
+    }
+}
+
+export class Method extends MethodDataType {
+    public constructor(abi: MethodAbi) {
+        super(abi, EvmDataTypeFactory.getInstance());
+    }
+}
+
+/* tslint:disable no-construct */
+export class EvmDataTypeFactory implements DataTypeFactory {
+    private static _instance: DataTypeFactory;
+
+    public static getInstance(): DataTypeFactory {
+        if (!EvmDataTypeFactory._instance) {
+            EvmDataTypeFactory._instance = new EvmDataTypeFactory();
+        }
+        return EvmDataTypeFactory._instance;
+    }
+
+    /* tslint:disable prefer-function-over-method */
+    public create(dataItem: DataItem, parentDataType?: DataType): DataType {
+        // Create data type
+        let dataType: undefined | DataType;
+        if (Array.matchType(dataItem.type)) {
+            dataType = new Array(dataItem);
+        } else if (Address.matchType(dataItem.type)) {
+            dataType = new Address(dataItem);
+        } else if (Bool.matchType(dataItem.type)) {
+            dataType = new Bool(dataItem);
+        } else if (Int.matchType(dataItem.type)) {
+            dataType = new Int(dataItem);
+        } else if (UInt.matchType(dataItem.type)) {
+            dataType = new UInt(dataItem);
+        } else if (StaticBytes.matchType(dataItem.type)) {
+            dataType = new StaticBytes(dataItem);
+        } else if (Tuple.matchType(dataItem.type)) {
+            dataType = new Tuple(dataItem);
+        } else if (DynamicBytes.matchType(dataItem.type)) {
+            dataType = new DynamicBytes(dataItem);
+        } else if (String.matchType(dataItem.type)) {
+            dataType = new String(dataItem);
+        }
+        // @TODO: DataTypeement Fixed/UFixed types
+        if (_.isUndefined(dataType)) {
+            throw new Error(`Unrecognized data type: '${dataItem.type}'`);
+        } else if (!_.isUndefined(parentDataType) && !dataType.isStatic()) {
+            const pointerToDataType = new Pointer(dataType, parentDataType);
+            return pointerToDataType;
+        }
+        return dataType;
+    }
+    /* tslint:enable prefer-function-over-method */
+
+    private constructor() {}
+}
+/* tslint:enable no-construct */
diff --git a/packages/utils/src/abi_encoder/evm_data_types/address.ts b/packages/utils/src/abi_encoder/evm_data_types/address.ts
new file mode 100644
index 000000000..88846b1fa
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/address.ts
@@ -0,0 +1,49 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractBlobDataType } from '../abstract_data_types/types/blob';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+
+export class AddressDataType extends AbstractBlobDataType {
+    private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
+    private static readonly _ADDRESS_SIZE_IN_BYTES = 20;
+    private static readonly _DECODED_ADDRESS_OFFSET_IN_BYTES = constants.EVM_WORD_WIDTH_IN_BYTES -
+    AddressDataType._ADDRESS_SIZE_IN_BYTES;
+
+    public static matchType(type: string): boolean {
+        return type === SolidityTypes.Address;
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory, AddressDataType._SIZE_KNOWN_AT_COMPILE_TIME);
+        if (!AddressDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate Address with bad input: ${dataItem}`);
+        }
+    }
+
+    // Disable prefer-function-over-method for inherited abstract methods.
+    /* tslint:disable prefer-function-over-method */
+    public encodeValue(value: string): Buffer {
+        if (!ethUtil.isValidAddress(value)) {
+            throw new Error(`Invalid address: '${value}'`);
+        }
+        const valueBuf = ethUtil.toBuffer(value);
+        const encodedValueBuf = ethUtil.setLengthLeft(valueBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
+        return encodedValueBuf;
+    }
+
+    public decodeValue(calldata: RawCalldata): string {
+        const valueBufPadded = calldata.popWord();
+        const valueBuf = valueBufPadded.slice(AddressDataType._DECODED_ADDRESS_OFFSET_IN_BYTES);
+        const value = ethUtil.bufferToHex(valueBuf);
+        return value;
+    }
+
+    public getSignature(): string {
+        return SolidityTypes.Address;
+    }
+    /* tslint:enable prefer-function-over-method */
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/array.ts b/packages/utils/src/abi_encoder/evm_data_types/array.ts
new file mode 100644
index 000000000..7595cb667
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/array.ts
@@ -0,0 +1,64 @@
+import { DataItem } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractSetDataType } from '../abstract_data_types/types/set';
+import { constants } from '../utils/constants';
+
+export class ArrayDataType extends AbstractSetDataType {
+    private static readonly _MATCHER = RegExp('^(.+)\\[([0-9]*)\\]$');
+    private readonly _arraySignature: string;
+    private readonly _elementType: string;
+
+    public static matchType(type: string): boolean {
+        return ArrayDataType._MATCHER.test(type);
+    }
+
+    private static _decodeElementTypeAndLengthFromType(type: string): [string, undefined | number] {
+        const matches = ArrayDataType._MATCHER.exec(type);
+        if (_.isNull(matches) || matches.length !== 3) {
+            throw new Error(`Could not parse array: ${type}`);
+        } else if (_.isUndefined(matches[1])) {
+            throw new Error(`Could not parse array type: ${type}`);
+        } else if (_.isUndefined(matches[2])) {
+            throw new Error(`Could not parse array length: ${type}`);
+        }
+        const arrayElementType = matches[1];
+        const arrayLength = _.isEmpty(matches[2]) ? undefined : parseInt(matches[2], constants.DEC_BASE);
+        return [arrayElementType, arrayLength];
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        // Construct parent
+        const isArray = true;
+        const [arrayElementType, arrayLength] = ArrayDataType._decodeElementTypeAndLengthFromType(dataItem.type);
+        super(dataItem, dataTypeFactory, isArray, arrayLength, arrayElementType);
+        // Set array properties
+        this._elementType = arrayElementType;
+        this._arraySignature = this._computeSignature();
+    }
+
+    public getSignature(): string {
+        return this._arraySignature;
+    }
+
+    private _computeSignature(): string {
+        // Compute signature for a single array element
+        const elementDataItem: DataItem = {
+            type: this._elementType,
+            name: 'N/A',
+        };
+        const elementComponents = this.getDataItem().components;
+        if (!_.isUndefined(elementComponents)) {
+            elementDataItem.components = elementComponents;
+        }
+        const elementDataType = this.getFactory().create(elementDataItem);
+        const elementSignature = elementDataType.getSignature();
+        // Construct signature for array of type `element`
+        if (_.isUndefined(this._arrayLength)) {
+            return `${elementSignature}[]`;
+        } else {
+            return `${elementSignature}[${this._arrayLength}]`;
+        }
+    }
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/bool.ts b/packages/utils/src/abi_encoder/evm_data_types/bool.ts
new file mode 100644
index 000000000..d713d5a94
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/bool.ts
@@ -0,0 +1,53 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { BigNumber } from '../../configured_bignumber';
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractBlobDataType } from '../abstract_data_types/types/blob';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+
+export class BoolDataType extends AbstractBlobDataType {
+    private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
+
+    public static matchType(type: string): boolean {
+        return type === SolidityTypes.Bool;
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory, BoolDataType._SIZE_KNOWN_AT_COMPILE_TIME);
+        if (!BoolDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate Bool with bad input: ${dataItem}`);
+        }
+    }
+
+    // Disable prefer-function-over-method for inherited abstract methods.
+    /* tslint:disable prefer-function-over-method */
+    public encodeValue(value: boolean): Buffer {
+        const encodedValue = value ? '0x1' : '0x0';
+        const encodedValueBuf = ethUtil.setLengthLeft(
+            ethUtil.toBuffer(encodedValue),
+            constants.EVM_WORD_WIDTH_IN_BYTES,
+        );
+        return encodedValueBuf;
+    }
+
+    public decodeValue(calldata: RawCalldata): boolean {
+        const valueBuf = calldata.popWord();
+        const valueHex = ethUtil.bufferToHex(valueBuf);
+        const valueNumber = new BigNumber(valueHex, constants.HEX_BASE);
+        if (!(valueNumber.equals(0) || valueNumber.equals(1))) {
+            throw new Error(`Failed to decode boolean. Expected 0x0 or 0x1, got ${valueHex}`);
+        }
+        /* tslint:disable boolean-naming */
+        const value: boolean = !valueNumber.equals(0);
+        /* tslint:enable boolean-naming */
+        return value;
+    }
+
+    public getSignature(): string {
+        return SolidityTypes.Bool;
+    }
+    /* tslint:enable prefer-function-over-method */
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/dynamic_bytes.ts b/packages/utils/src/abi_encoder/evm_data_types/dynamic_bytes.ts
new file mode 100644
index 000000000..5277efd6c
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/dynamic_bytes.ts
@@ -0,0 +1,72 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractBlobDataType } from '../abstract_data_types/types/blob';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+
+export class DynamicBytesDataType extends AbstractBlobDataType {
+    private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = false;
+
+    public static matchType(type: string): boolean {
+        return type === SolidityTypes.Bytes;
+    }
+
+    private static _sanityCheckValue(value: string | Buffer): void {
+        if (typeof value !== 'string') {
+            return;
+        }
+        if (!_.startsWith(value, '0x')) {
+            throw new Error(`Tried to encode non-hex value. Value must inlcude '0x' prefix.`);
+        } else if (value.length % 2 !== 0) {
+            throw new Error(`Tried to assign ${value}, which is contains a half-byte. Use full bytes only.`);
+        }
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory, DynamicBytesDataType._SIZE_KNOWN_AT_COMPILE_TIME);
+        if (!DynamicBytesDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate Dynamic Bytes with bad input: ${dataItem}`);
+        }
+    }
+
+    // Disable prefer-function-over-method for inherited abstract methods.
+    /* tslint:disable prefer-function-over-method */
+    public encodeValue(value: string | Buffer): Buffer {
+        // Encoded value is of the form: <length><value>, with each field padded to be word-aligned.
+        // 1/3 Construct the length
+        const valueBuf = ethUtil.toBuffer(value);
+        const wordsToStoreValuePadded = Math.ceil(valueBuf.byteLength / constants.EVM_WORD_WIDTH_IN_BYTES);
+        const bytesToStoreValuePadded = wordsToStoreValuePadded * constants.EVM_WORD_WIDTH_IN_BYTES;
+        const lengthBuf = ethUtil.toBuffer(valueBuf.byteLength);
+        const lengthBufPadded = ethUtil.setLengthLeft(lengthBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
+        // 2/3 Construct the value
+        DynamicBytesDataType._sanityCheckValue(value);
+        const valueBufPadded = ethUtil.setLengthRight(valueBuf, bytesToStoreValuePadded);
+        // 3/3 Combine length and value
+        const encodedValue = Buffer.concat([lengthBufPadded, valueBufPadded]);
+        return encodedValue;
+    }
+
+    public decodeValue(calldata: RawCalldata): string {
+        // Encoded value is of the form: <length><value>, with each field padded to be word-aligned.
+        // 1/2 Decode length
+        const lengthBuf = calldata.popWord();
+        const lengthHex = ethUtil.bufferToHex(lengthBuf);
+        const length = parseInt(lengthHex, constants.HEX_BASE);
+        // 2/2 Decode value
+        const wordsToStoreValuePadded = Math.ceil(length / constants.EVM_WORD_WIDTH_IN_BYTES);
+        const valueBufPadded = calldata.popWords(wordsToStoreValuePadded);
+        const valueBuf = valueBufPadded.slice(0, length);
+        const value = ethUtil.bufferToHex(valueBuf);
+        DynamicBytesDataType._sanityCheckValue(value);
+        return value;
+    }
+
+    public getSignature(): string {
+        return SolidityTypes.Bytes;
+    }
+    /* tslint:enable prefer-function-over-method */
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/int.ts b/packages/utils/src/abi_encoder/evm_data_types/int.ts
new file mode 100644
index 000000000..f1dcf5ea1
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/int.ts
@@ -0,0 +1,59 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { BigNumber } from '../../configured_bignumber';
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractBlobDataType } from '../abstract_data_types/types/blob';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+import * as EncoderMath from '../utils/math';
+
+export class IntDataType extends AbstractBlobDataType {
+    private static readonly _MATCHER = RegExp(
+        '^int(8|16|24|32|40|48|56|64|72|88|96|104|112|120|128|136|144|152|160|168|176|184|192|200|208|216|224|232|240|248|256){0,1}$',
+    );
+    private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
+    private static readonly _MAX_WIDTH: number = 256;
+    private static readonly _DEFAULT_WIDTH: number = IntDataType._MAX_WIDTH;
+    private readonly _width: number;
+    private readonly _minValue: BigNumber;
+    private readonly _maxValue: BigNumber;
+
+    public static matchType(type: string): boolean {
+        return IntDataType._MATCHER.test(type);
+    }
+
+    private static _decodeWidthFromType(type: string): number {
+        const matches = IntDataType._MATCHER.exec(type);
+        const width =
+            !_.isNull(matches) && matches.length === 2 && !_.isUndefined(matches[1])
+                ? parseInt(matches[1], constants.DEC_BASE)
+                : IntDataType._DEFAULT_WIDTH;
+        return width;
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory, IntDataType._SIZE_KNOWN_AT_COMPILE_TIME);
+        if (!IntDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate Int with bad input: ${dataItem}`);
+        }
+        this._width = IntDataType._decodeWidthFromType(dataItem.type);
+        this._minValue = new BigNumber(2).toPower(this._width - 1).times(-1);
+        this._maxValue = new BigNumber(2).toPower(this._width - 1).sub(1);
+    }
+
+    public encodeValue(value: BigNumber | string | number): Buffer {
+        const encodedValue = EncoderMath.safeEncodeNumericValue(value, this._minValue, this._maxValue);
+        return encodedValue;
+    }
+
+    public decodeValue(calldata: RawCalldata): BigNumber {
+        const valueBuf = calldata.popWord();
+        const value = EncoderMath.safeDecodeNumericValue(valueBuf, this._minValue, this._maxValue);
+        return value;
+    }
+
+    public getSignature(): string {
+        return `${SolidityTypes.Int}${this._width}`;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/method.ts b/packages/utils/src/abi_encoder/evm_data_types/method.ts
new file mode 100644
index 000000000..b1cd1377f
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/method.ts
@@ -0,0 +1,72 @@
+import { DataItem, MethodAbi } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { DataType } from '../abstract_data_types/data_type';
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractSetDataType } from '../abstract_data_types/types/set';
+import { constants } from '../utils/constants';
+import { DecodingRules, EncodingRules } from '../utils/rules';
+
+import { TupleDataType } from './tuple';
+
+export class MethodDataType extends AbstractSetDataType {
+    private readonly _methodSignature: string;
+    private readonly _methodSelector: string;
+    private readonly _returnDataType: DataType;
+
+    public constructor(abi: MethodAbi, dataTypeFactory: DataTypeFactory) {
+        const methodDataItem = { type: 'method', name: abi.name, components: abi.inputs };
+        super(methodDataItem, dataTypeFactory);
+        this._methodSignature = this._computeSignature();
+        this._methodSelector = this._computeSelector();
+        const returnDataItem: DataItem = { type: 'tuple', name: abi.name, components: abi.outputs };
+        this._returnDataType = new TupleDataType(returnDataItem, this.getFactory());
+    }
+
+    public encode(value: any, rules?: EncodingRules): string {
+        const calldata = super.encode(value, rules, this._methodSelector);
+        return calldata;
+    }
+
+    public decode(calldata: string, rules?: DecodingRules): any[] | object {
+        const value = super.decode(calldata, rules, this._methodSelector);
+        return value;
+    }
+
+    public encodeReturnValues(value: any, rules?: EncodingRules): string {
+        const returnData = this._returnDataType.encode(value, rules);
+        return returnData;
+    }
+
+    public decodeReturnValues(returndata: string, rules?: DecodingRules): any {
+        const returnValues = this._returnDataType.decode(returndata, rules);
+        return returnValues;
+    }
+
+    public getSignature(): string {
+        return this._methodSignature;
+    }
+
+    public getSelector(): string {
+        return this._methodSelector;
+    }
+
+    private _computeSignature(): string {
+        const memberSignature = this._computeSignatureOfMembers();
+        const methodSignature = `${this.getDataItem().name}${memberSignature}`;
+        return methodSignature;
+    }
+
+    private _computeSelector(): string {
+        const signature = this._computeSignature();
+        const selector = ethUtil.bufferToHex(
+            ethUtil.toBuffer(
+                ethUtil
+                    .sha3(signature)
+                    .slice(constants.HEX_SELECTOR_BYTE_OFFSET_IN_CALLDATA, constants.HEX_SELECTOR_LENGTH_IN_BYTES),
+            ),
+        );
+        return selector;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/pointer.ts b/packages/utils/src/abi_encoder/evm_data_types/pointer.ts
new file mode 100644
index 000000000..389e75927
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/pointer.ts
@@ -0,0 +1,17 @@
+import { DataItem } from 'ethereum-types';
+
+import { DataType } from '../abstract_data_types/data_type';
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractPointerDataType } from '../abstract_data_types/types/pointer';
+
+export class PointerDataType extends AbstractPointerDataType {
+    constructor(destDataType: DataType, parentDataType: DataType, dataTypeFactory: DataTypeFactory) {
+        const destDataItem = destDataType.getDataItem();
+        const dataItem: DataItem = { name: `ptr<${destDataItem.name}>`, type: `ptr<${destDataItem.type}>` };
+        super(dataItem, dataTypeFactory, destDataType, parentDataType);
+    }
+
+    public getSignature(): string {
+        return this._destination.getSignature();
+    }
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts b/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
new file mode 100644
index 000000000..2e371c505
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
@@ -0,0 +1,78 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractBlobDataType } from '../abstract_data_types/types/blob';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+
+export class StaticBytesDataType extends AbstractBlobDataType {
+    private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
+    private static readonly _MATCHER = RegExp(
+        '^(byte|bytes(1|2|3|4|5|6|7|8|9|10|11|12|13|14|15|16|17|18|19|20|21|22|23|24|25|26|27|28|29|30|31|32))$',
+    );
+    private static readonly _DEFAULT_WIDTH = 1;
+    private readonly _width: number;
+
+    public static matchType(type: string): boolean {
+        return StaticBytesDataType._MATCHER.test(type);
+    }
+
+    private static _decodeWidthFromType(type: string): number {
+        const matches = StaticBytesDataType._MATCHER.exec(type);
+        const width =
+            !_.isNull(matches) && matches.length === 3 && !_.isUndefined(matches[2])
+                ? parseInt(matches[2], constants.DEC_BASE)
+                : StaticBytesDataType._DEFAULT_WIDTH;
+        return width;
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory, StaticBytesDataType._SIZE_KNOWN_AT_COMPILE_TIME);
+        if (!StaticBytesDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate Static Bytes with bad input: ${dataItem}`);
+        }
+        this._width = StaticBytesDataType._decodeWidthFromType(dataItem.type);
+    }
+
+    public getSignature(): string {
+        // Note that `byte` reduces to `bytes1`
+        return `${SolidityTypes.Bytes}${this._width}`;
+    }
+
+    public encodeValue(value: string | Buffer): Buffer {
+        // 1/2 Convert value into a buffer and do bounds checking
+        this._sanityCheckValue(value);
+        const valueBuf = ethUtil.toBuffer(value);
+        // 2/2 Store value as hex
+        const valuePadded = ethUtil.setLengthRight(valueBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
+        return valuePadded;
+    }
+
+    public decodeValue(calldata: RawCalldata): string {
+        const valueBufPadded = calldata.popWord();
+        const valueBuf = valueBufPadded.slice(0, this._width);
+        const value = ethUtil.bufferToHex(valueBuf);
+        this._sanityCheckValue(value);
+        return value;
+    }
+
+    private _sanityCheckValue(value: string | Buffer): void {
+        if (typeof value === 'string') {
+            if (!_.startsWith(value, '0x')) {
+                throw new Error(`Tried to encode non-hex value. Value must inlcude '0x' prefix.`);
+            } else if (value.length % 2 !== 0) {
+                throw new Error(`Tried to assign ${value}, which is contains a half-byte. Use full bytes only.`);
+            }
+        }
+        const valueBuf = ethUtil.toBuffer(value);
+        if (valueBuf.byteLength > this._width) {
+            throw new Error(
+                `Tried to assign ${value} (${
+                    valueBuf.byteLength
+                } bytes), which exceeds max bytes that can be stored in a ${this.getSignature()}`,
+            );
+        }
+    }
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/string.ts b/packages/utils/src/abi_encoder/evm_data_types/string.ts
new file mode 100644
index 000000000..91a72ad3f
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/string.ts
@@ -0,0 +1,59 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractBlobDataType } from '../abstract_data_types/types/blob';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+
+export class StringDataType extends AbstractBlobDataType {
+    private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = false;
+
+    public static matchType(type: string): boolean {
+        return type === SolidityTypes.String;
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory, StringDataType._SIZE_KNOWN_AT_COMPILE_TIME);
+        if (!StringDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate String with bad input: ${dataItem}`);
+        }
+    }
+
+    // Disable prefer-function-over-method for inherited abstract methods.
+    /* tslint:disable prefer-function-over-method */
+    public encodeValue(value: string): Buffer {
+        // Encoded value is of the form: <length><value>, with each field padded to be word-aligned.
+        // 1/3 Construct the length
+        const wordsToStoreValuePadded = Math.ceil(value.length / constants.EVM_WORD_WIDTH_IN_BYTES);
+        const bytesToStoreValuePadded = wordsToStoreValuePadded * constants.EVM_WORD_WIDTH_IN_BYTES;
+        const lengthBuf = ethUtil.toBuffer(value.length);
+        const lengthBufPadded = ethUtil.setLengthLeft(lengthBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
+        // 2/3 Construct the value
+        const valueBuf = new Buffer(value);
+        const valueBufPadded = ethUtil.setLengthRight(valueBuf, bytesToStoreValuePadded);
+        // 3/3 Combine length and value
+        const encodedValue = Buffer.concat([lengthBufPadded, valueBufPadded]);
+        return encodedValue;
+    }
+
+    public decodeValue(calldata: RawCalldata): string {
+        // Encoded value is of the form: <length><value>, with each field padded to be word-aligned.
+        // 1/2 Decode length
+        const lengthBufPadded = calldata.popWord();
+        const lengthHexPadded = ethUtil.bufferToHex(lengthBufPadded);
+        const length = parseInt(lengthHexPadded, constants.HEX_BASE);
+        // 2/2 Decode value
+        const wordsToStoreValuePadded = Math.ceil(length / constants.EVM_WORD_WIDTH_IN_BYTES);
+        const valueBufPadded = calldata.popWords(wordsToStoreValuePadded);
+        const valueBuf = valueBufPadded.slice(0, length);
+        const value = valueBuf.toString('ascii');
+        return value;
+    }
+
+    public getSignature(): string {
+        return SolidityTypes.String;
+    }
+    /* tslint:enable prefer-function-over-method */
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/tuple.ts b/packages/utils/src/abi_encoder/evm_data_types/tuple.ts
new file mode 100644
index 000000000..31593c882
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/tuple.ts
@@ -0,0 +1,24 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractSetDataType } from '../abstract_data_types/types/set';
+
+export class TupleDataType extends AbstractSetDataType {
+    private readonly _signature: string;
+
+    public static matchType(type: string): boolean {
+        return type === SolidityTypes.Tuple;
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory);
+        if (!TupleDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate Tuple with bad input: ${dataItem}`);
+        }
+        this._signature = this._computeSignatureOfMembers();
+    }
+
+    public getSignature(): string {
+        return this._signature;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/evm_data_types/uint.ts b/packages/utils/src/abi_encoder/evm_data_types/uint.ts
new file mode 100644
index 000000000..5180f0cf3
--- /dev/null
+++ b/packages/utils/src/abi_encoder/evm_data_types/uint.ts
@@ -0,0 +1,58 @@
+import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as _ from 'lodash';
+
+import { BigNumber } from '../../configured_bignumber';
+import { DataTypeFactory } from '../abstract_data_types/interfaces';
+import { AbstractBlobDataType } from '../abstract_data_types/types/blob';
+import { RawCalldata } from '../calldata/raw_calldata';
+import { constants } from '../utils/constants';
+import * as EncoderMath from '../utils/math';
+
+export class UIntDataType extends AbstractBlobDataType {
+    private static readonly _MATCHER = RegExp(
+        '^uint(8|16|24|32|40|48|56|64|72|88|96|104|112|120|128|136|144|152|160|168|176|184|192|200|208|216|224|232|240|248|256){0,1}$',
+    );
+    private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
+    private static readonly _MAX_WIDTH: number = 256;
+    private static readonly _DEFAULT_WIDTH: number = UIntDataType._MAX_WIDTH;
+    private static readonly _MIN_VALUE = new BigNumber(0);
+    private readonly _width: number;
+    private readonly _maxValue: BigNumber;
+
+    public static matchType(type: string): boolean {
+        return UIntDataType._MATCHER.test(type);
+    }
+
+    private static _decodeWidthFromType(type: string): number {
+        const matches = UIntDataType._MATCHER.exec(type);
+        const width =
+            !_.isNull(matches) && matches.length === 2 && !_.isUndefined(matches[1])
+                ? parseInt(matches[1], constants.DEC_BASE)
+                : UIntDataType._DEFAULT_WIDTH;
+        return width;
+    }
+
+    public constructor(dataItem: DataItem, dataTypeFactory: DataTypeFactory) {
+        super(dataItem, dataTypeFactory, UIntDataType._SIZE_KNOWN_AT_COMPILE_TIME);
+        if (!UIntDataType.matchType(dataItem.type)) {
+            throw new Error(`Tried to instantiate UInt with bad input: ${dataItem}`);
+        }
+        this._width = UIntDataType._decodeWidthFromType(dataItem.type);
+        this._maxValue = new BigNumber(2).toPower(this._width).sub(1);
+    }
+
+    public encodeValue(value: BigNumber | string | number): Buffer {
+        const encodedValue = EncoderMath.safeEncodeNumericValue(value, UIntDataType._MIN_VALUE, this._maxValue);
+        return encodedValue;
+    }
+
+    public decodeValue(calldata: RawCalldata): BigNumber {
+        const valueBuf = calldata.popWord();
+        const value = EncoderMath.safeDecodeNumericValue(valueBuf, UIntDataType._MIN_VALUE, this._maxValue);
+        return value;
+    }
+
+    public getSignature(): string {
+        return `${SolidityTypes.Uint}${this._width}`;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/index.ts b/packages/utils/src/abi_encoder/index.ts
new file mode 100644
index 000000000..baf844ac6
--- /dev/null
+++ b/packages/utils/src/abi_encoder/index.ts
@@ -0,0 +1,14 @@
+export { EncodingRules, DecodingRules } from './utils/rules';
+export {
+    Address,
+    Array,
+    Bool,
+    DynamicBytes,
+    Int,
+    Method,
+    Pointer,
+    StaticBytes,
+    String,
+    Tuple,
+    UInt,
+} from './evm_data_type_factory';
diff --git a/packages/utils/src/abi_encoder/utils/constants.ts b/packages/utils/src/abi_encoder/utils/constants.ts
new file mode 100644
index 000000000..2f43ba04d
--- /dev/null
+++ b/packages/utils/src/abi_encoder/utils/constants.ts
@@ -0,0 +1,17 @@
+import { DecodingRules, EncodingRules } from './rules';
+
+export const constants = {
+    EVM_WORD_WIDTH_IN_BYTES: 32,
+    EVM_WORD_WIDTH_IN_BITS: 256,
+    HEX_BASE: 16,
+    DEC_BASE: 10,
+    BIN_BASE: 2,
+    HEX_SELECTOR_LENGTH_IN_CHARS: 10,
+    HEX_SELECTOR_LENGTH_IN_BYTES: 4,
+    HEX_SELECTOR_BYTE_OFFSET_IN_CALLDATA: 0,
+    // Disable no-object-literal-type-assertion so we can enforce cast
+    /* tslint:disable no-object-literal-type-assertion */
+    DEFAULT_DECODING_RULES: { structsAsObjects: false } as DecodingRules,
+    DEFAULT_ENCODING_RULES: { optimize: true, annotate: false } as EncodingRules,
+    /* tslint:enable no-object-literal-type-assertion */
+};
diff --git a/packages/utils/src/abi_encoder/utils/math.ts b/packages/utils/src/abi_encoder/utils/math.ts
new file mode 100644
index 000000000..d84983c5b
--- /dev/null
+++ b/packages/utils/src/abi_encoder/utils/math.ts
@@ -0,0 +1,111 @@
+import BigNumber from 'bignumber.js';
+import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
+import { constants } from '../utils/constants';
+
+function sanityCheckBigNumberRange(
+    value_: BigNumber | string | number,
+    minValue: BigNumber,
+    maxValue: BigNumber,
+): void {
+    const value = new BigNumber(value_, 10);
+    if (value.greaterThan(maxValue)) {
+        throw new Error(`Tried to assign value of ${value}, which exceeds max value of ${maxValue}`);
+    } else if (value.lessThan(minValue)) {
+        throw new Error(`Tried to assign value of ${value}, which exceeds min value of ${minValue}`);
+    }
+}
+function bigNumberToPaddedBuffer(value: BigNumber): Buffer {
+    const valueHex = `0x${value.toString(constants.HEX_BASE)}`;
+    const valueBuf = ethUtil.toBuffer(valueHex);
+    const valueBufPadded = ethUtil.setLengthLeft(valueBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
+    return valueBufPadded;
+}
+/**
+ * Takes a numeric value and returns its ABI-encoded value
+ * @param value_    The value to encode.
+ * @return ABI Encoded value
+ */
+export function encodeNumericValue(value_: BigNumber | string | number): Buffer {
+    const value = new BigNumber(value_, 10);
+    // Case 1/2: value is non-negative
+    if (value.greaterThanOrEqualTo(0)) {
+        const encodedPositiveValue = bigNumberToPaddedBuffer(value);
+        return encodedPositiveValue;
+    }
+    // Case 2/2: Value is negative
+    // Use two's-complement to encode the value
+    // Step 1/3: Convert negative value to positive binary string
+    const valueBin = value.times(-1).toString(constants.BIN_BASE);
+    // Step 2/3: Invert binary value
+    let invertedValueBin = '1'.repeat(constants.EVM_WORD_WIDTH_IN_BITS - valueBin.length);
+    _.each(valueBin, (bit: string) => {
+        invertedValueBin += bit === '1' ? '0' : '1';
+    });
+    const invertedValue = new BigNumber(invertedValueBin, constants.BIN_BASE);
+    // Step 3/3: Add 1 to inverted value
+    const negativeValue = invertedValue.plus(1);
+    const encodedValue = bigNumberToPaddedBuffer(negativeValue);
+    return encodedValue;
+}
+/**
+ * Takes a numeric value and returns its ABI-encoded value.
+ * Performs an additional sanity check, given the min/max allowed value.
+ * @param value_    The value to encode.
+ * @return ABI Encoded value
+ */
+export function safeEncodeNumericValue(
+    value: BigNumber | string | number,
+    minValue: BigNumber,
+    maxValue: BigNumber,
+): Buffer {
+    sanityCheckBigNumberRange(value, minValue, maxValue);
+    const encodedValue = encodeNumericValue(value);
+    return encodedValue;
+}
+/**
+ * Takes an ABI-encoded numeric value and returns its decoded value as a BigNumber.
+ * @param encodedValue    The encoded numeric value.
+ * @param minValue        The minimum possible decoded value.
+ * @return ABI Decoded value
+ */
+export function decodeNumericValue(encodedValue: Buffer, minValue: BigNumber): BigNumber {
+    const valueHex = ethUtil.bufferToHex(encodedValue);
+    // Case 1/3: value is definitely non-negative because of numeric boundaries
+    const value = new BigNumber(valueHex, constants.HEX_BASE);
+    if (!minValue.lessThan(0)) {
+        return value;
+    }
+    // Case 2/3: value is non-negative because there is no leading 1 (encoded as two's-complement)
+    const valueBin = value.toString(constants.BIN_BASE);
+    const isValueNegative = valueBin.length === constants.EVM_WORD_WIDTH_IN_BITS && _.startsWith(valueBin[0], '1');
+    if (!isValueNegative) {
+        return value;
+    }
+    // Case 3/3: value is negative
+    // Step 1/3: Invert b inary value
+    let invertedValueBin = '';
+    _.each(valueBin, (bit: string) => {
+        invertedValueBin += bit === '1' ? '0' : '1';
+    });
+    const invertedValue = new BigNumber(invertedValueBin, constants.BIN_BASE);
+    // Step 2/3: Add 1 to inverted value
+    // The result is the two's-complement representation of the input value.
+    const positiveValue = invertedValue.plus(1);
+    // Step 3/3: Invert positive value to get the negative value
+    const negativeValue = positiveValue.times(-1);
+    return negativeValue;
+}
+/**
+ * Takes an ABI-encoded numeric value and returns its decoded value as a BigNumber.
+ * Performs an additional sanity check, given the min/max allowed value.
+ * @param encodedValue    The encoded numeric value.
+ * @param minValue        The minimum possible decoded value.
+ * @return ABI Decoded value
+ */
+export function safeDecodeNumericValue(encodedValue: Buffer, minValue: BigNumber, maxValue: BigNumber): BigNumber {
+    const value = decodeNumericValue(encodedValue, minValue);
+    sanityCheckBigNumberRange(value, minValue, maxValue);
+    return value;
+}
diff --git a/packages/utils/src/abi_encoder/utils/queue.ts b/packages/utils/src/abi_encoder/utils/queue.ts
new file mode 100644
index 000000000..53afb7e11
--- /dev/null
+++ b/packages/utils/src/abi_encoder/utils/queue.ts
@@ -0,0 +1,39 @@
+export class Queue<T> {
+    private _store: T[] = [];
+
+    public pushBack(val: T): void {
+        this._store.push(val);
+    }
+
+    public pushFront(val: T): void {
+        this._store.unshift(val);
+    }
+
+    public popFront(): T | undefined {
+        return this._store.shift();
+    }
+
+    public popBack(): T | undefined {
+        if (this._store.length === 0) {
+            return undefined;
+        }
+        const backElement = this._store.splice(-1, 1)[0];
+        return backElement;
+    }
+
+    public mergeBack(q: Queue<T>): void {
+        this._store = this._store.concat(q._store);
+    }
+
+    public mergeFront(q: Queue<T>): void {
+        this._store = q._store.concat(this._store);
+    }
+
+    public getStore(): T[] {
+        return this._store;
+    }
+
+    public peekFront(): T | undefined {
+        return this._store.length >= 0 ? this._store[0] : undefined;
+    }
+}
diff --git a/packages/utils/src/abi_encoder/utils/rules.ts b/packages/utils/src/abi_encoder/utils/rules.ts
new file mode 100644
index 000000000..31471e97a
--- /dev/null
+++ b/packages/utils/src/abi_encoder/utils/rules.ts
@@ -0,0 +1,8 @@
+export interface DecodingRules {
+    structsAsObjects: boolean;
+}
+
+export interface EncodingRules {
+    optimize?: boolean;
+    annotate?: boolean;
+}
diff --git a/packages/utils/src/index.ts b/packages/utils/src/index.ts
index 0723e5788..082aff6bb 100644
--- a/packages/utils/src/index.ts
+++ b/packages/utils/src/index.ts
@@ -10,3 +10,4 @@ export { NULL_BYTES } from './constants';
 export { errorUtils } from './error_utils';
 export { fetchAsync } from './fetch_async';
 export { signTypedDataUtils } from './sign_typed_data_utils';
+export import AbiEncoder = require('./abi_encoder');
diff --git a/packages/utils/test/abi_encoder/abi_samples/method_abis.ts b/packages/utils/test/abi_encoder/abi_samples/method_abis.ts
new file mode 100644
index 000000000..fc552c127
--- /dev/null
+++ b/packages/utils/test/abi_encoder/abi_samples/method_abis.ts
@@ -0,0 +1,780 @@
+/* tslint:disable max-file-line-count */
+import { MethodAbi } from 'ethereum-types';
+
+export const simpleAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'greg',
+            type: 'uint256',
+        },
+        {
+            name: 'gregStr',
+            type: 'string',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const stringAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'greg',
+            type: 'string[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const GAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'a',
+                    type: 'uint256',
+                },
+                {
+                    name: 'b',
+                    type: 'string',
+                },
+                {
+                    name: 'e',
+                    type: 'bytes',
+                },
+                {
+                    name: 'f',
+                    type: 'address',
+                },
+            ],
+
+            name: 'f',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const typesWithDefaultWidthsAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someUint',
+            type: 'uint',
+        },
+        {
+            name: 'someInt',
+            type: 'int',
+        },
+        {
+            name: 'someByte',
+            type: 'byte',
+        },
+        {
+            name: 'someUint',
+            type: 'uint[]',
+        },
+        {
+            name: 'someInt',
+            type: 'int[]',
+        },
+        {
+            name: 'someByte',
+            type: 'byte[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const multiDimensionalArraysStaticTypeAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'a',
+            type: 'uint8[][][]',
+        },
+        {
+            name: 'b',
+            type: 'uint8[][][2]',
+        },
+        {
+            name: 'c',
+            type: 'uint8[][2][]',
+        },
+        {
+            name: 'd',
+            type: 'uint8[2][][]',
+        },
+        {
+            name: 'e',
+            type: 'uint8[][2][2]',
+        },
+        {
+            name: 'f',
+            type: 'uint8[2][2][]',
+        },
+        {
+            name: 'g',
+            type: 'uint8[2][][2]',
+        },
+        {
+            name: 'h',
+            type: 'uint8[2][2][2]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const multiDimensionalArraysDynamicTypeAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'a',
+            type: 'string[][][]',
+        },
+        {
+            name: 'b',
+            type: 'string[][][2]',
+        },
+        {
+            name: 'c',
+            type: 'string[][2][]',
+        },
+        {
+            name: 'h',
+            type: 'string[2][2][2]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const dynamicTupleAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+            ],
+            name: 'order',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const arrayOfStaticTuplesWithDefinedLengthAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someUint2',
+                    type: 'uint256',
+                },
+            ],
+            name: 'order',
+            type: 'tuple[8]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const arrayOfStaticTuplesWithDynamicLengthAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someUint2',
+                    type: 'uint256',
+                },
+            ],
+            name: 'order',
+            type: 'tuple[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const arrayOfDynamicTuplesWithDefinedLengthAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someString',
+                    type: 'string',
+                },
+            ],
+            name: 'order',
+            type: 'tuple[8]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const arrayOfDynamicTuplesWithUndefinedLengthAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someString',
+                    type: 'string',
+                },
+            ],
+            name: 'order',
+            type: 'tuple[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const arrayOfDynamicTuplesAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someString',
+                    type: 'string',
+                },
+            ],
+            name: 'order',
+            type: 'tuple[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const multidimensionalArrayOfDynamicTuplesAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someString',
+                    type: 'string',
+                },
+            ],
+            name: 'order',
+            type: 'tuple[][2][]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const staticTupleAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'someUint1',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someUint2',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someUint3',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someBool',
+                    type: 'bool',
+                },
+            ],
+            name: 'order',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const staticArrayAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'uint8[3]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const staticArrayDynamicMembersAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'string[3]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const dynamicArrayDynamicMembersAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'string[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const dynamicArrayStaticMembersAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'uint8[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const largeFlatAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someUInt256',
+            type: 'uint256',
+        },
+        {
+            name: 'someInt256',
+            type: 'int256',
+        },
+        {
+            name: 'someInt32',
+            type: 'int32',
+        },
+        {
+            name: 'someByte',
+            type: 'byte',
+        },
+        {
+            name: 'someBytes32',
+            type: 'bytes32',
+        },
+        {
+            name: 'someBytes',
+            type: 'bytes',
+        },
+        {
+            name: 'someString',
+            type: 'string',
+        },
+        {
+            name: 'someAddress',
+            type: 'address',
+        },
+        {
+            name: 'someBool',
+            type: 'bool',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const largeNestedAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someStaticArray',
+            type: 'uint8[3]',
+        },
+        {
+            name: 'someStaticArrayWithDynamicMembers',
+            type: 'string[2]',
+        },
+        {
+            name: 'someDynamicArrayWithDynamicMembers',
+            type: 'bytes[]',
+        },
+        {
+            name: 'some2DArray',
+            type: 'string[][]',
+        },
+        {
+            name: 'someTuple',
+            type: 'tuple',
+            components: [
+                {
+                    name: 'someUint32',
+                    type: 'uint32',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+            ],
+        },
+        {
+            name: 'someTupleWithDynamicTypes',
+            type: 'tuple',
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+                /*{
+                    name: 'someStrArray',
+                    type: 'string[]',
+                },*/
+                {
+                    name: 'someBytes',
+                    type: 'bytes',
+                },
+                {
+                    name: 'someAddress',
+                    type: 'address',
+                },
+            ],
+        },
+        {
+            name: 'someArrayOfTuplesWithDynamicTypes',
+            type: 'tuple[]',
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+                /*{
+                    name: 'someStrArray',
+                    type: 'string[]',
+                },*/
+                {
+                    name: 'someBytes',
+                    type: 'bytes',
+                },
+                {
+                    name: 'someAddress',
+                    type: 'address',
+                },
+            ],
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const nestedTuples: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'firstTuple',
+            type: 'tuple[1]',
+            components: [
+                {
+                    name: 'someUint32',
+                    type: 'uint32',
+                },
+                {
+                    name: 'nestedTuple',
+                    type: 'tuple',
+                    components: [
+                        {
+                            name: 'someUint',
+                            type: 'uint256',
+                        },
+                        {
+                            name: 'someAddress',
+                            type: 'address',
+                        },
+                    ],
+                },
+            ],
+        },
+        {
+            name: 'secondTuple',
+            type: 'tuple[]',
+            components: [
+                {
+                    name: 'someUint',
+                    type: 'uint256',
+                },
+                {
+                    name: 'someStr',
+                    type: 'string',
+                },
+                {
+                    name: 'nestedTuple',
+                    type: 'tuple',
+                    components: [
+                        {
+                            name: 'someUint32',
+                            type: 'uint32',
+                        },
+                        {
+                            name: 'secondNestedTuple',
+                            type: 'tuple',
+                            components: [
+                                {
+                                    name: 'someUint',
+                                    type: 'uint256',
+                                },
+                                {
+                                    name: 'someStr',
+                                    type: 'string',
+                                },
+                                {
+                                    name: 'someBytes',
+                                    type: 'bytes',
+                                },
+                                {
+                                    name: 'someAddress',
+                                    type: 'address',
+                                },
+                            ],
+                        },
+                    ],
+                },
+                {
+                    name: 'someBytes',
+                    type: 'bytes',
+                },
+                {
+                    name: 'someAddress',
+                    type: 'address',
+                },
+            ],
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const simpleAbi2: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'someByte',
+            type: 'byte',
+        },
+        {
+            name: 'someBytes32',
+            type: 'bytes32',
+        },
+        {
+            name: 'someBytes',
+            type: 'bytes',
+        },
+        {
+            name: 'someString',
+            type: 'string',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const fillOrderAbi: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'makerAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'takerAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'feeRecipientAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'senderAddress',
+                    type: 'address',
+                },
+                {
+                    name: 'makerAssetAmount',
+                    type: 'uint256',
+                },
+                {
+                    name: 'takerAssetAmount',
+                    type: 'uint256',
+                },
+                {
+                    name: 'makerFee',
+                    type: 'uint256',
+                },
+                {
+                    name: 'takerFee',
+                    type: 'uint256',
+                },
+                {
+                    name: 'expirationTimeSeconds',
+                    type: 'uint256',
+                },
+                {
+                    name: 'salt',
+                    type: 'uint256',
+                },
+                {
+                    name: 'makerAssetData',
+                    type: 'bytes',
+                },
+                {
+                    name: 'takerAssetData',
+                    type: 'bytes',
+                },
+            ],
+            name: 'order',
+            type: 'tuple',
+        },
+        {
+            name: 'takerAssetFillAmount',
+            type: 'uint256',
+        },
+        {
+            name: 'salt',
+            type: 'uint256',
+        },
+        {
+            name: 'orderSignature',
+            type: 'bytes',
+        },
+        {
+            name: 'takerSignature',
+            type: 'bytes',
+        },
+    ],
+    name: 'fillOrder',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
diff --git a/packages/utils/test/abi_encoder/abi_samples/optimizer_abis.ts b/packages/utils/test/abi_encoder/abi_samples/optimizer_abis.ts
new file mode 100644
index 000000000..7cfd7a118
--- /dev/null
+++ b/packages/utils/test/abi_encoder/abi_samples/optimizer_abis.ts
@@ -0,0 +1,340 @@
+/* tslint:disable max-file-line-count */
+import { MethodAbi } from 'ethereum-types';
+
+export const duplicateDynamicArraysWithStaticElements: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'array1',
+            type: 'uint[]',
+        },
+        {
+            name: 'array2',
+            type: 'uint[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateDynamicArraysWithDynamicElements: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'array1',
+            type: 'string[]',
+        },
+        {
+            name: 'array2',
+            type: 'string[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateStaticArraysWithStaticElements: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'array1',
+            type: 'uint[2]',
+        },
+        {
+            name: 'array2',
+            type: 'uint[2]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateStaticArraysWithDynamicElements: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'array1',
+            type: 'string[2]',
+        },
+        {
+            name: 'array2',
+            type: 'string[2]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateArrayElements: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'array',
+            type: 'string[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateTupleFields: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'field1',
+                    type: 'string',
+                },
+                {
+                    name: 'field2',
+                    type: 'string',
+                },
+            ],
+            name: 'Tuple',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateStrings: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'string1',
+            type: 'string',
+        },
+        {
+            name: 'string2',
+            type: 'string',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateBytes: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'bytes1',
+            type: 'bytes',
+        },
+        {
+            name: 'bytes2',
+            type: 'bytes',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateTuples: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'field1',
+                    type: 'string',
+                },
+                {
+                    name: 'field2',
+                    type: 'uint',
+                },
+            ],
+            name: 'Tuple',
+            type: 'tuple',
+        },
+        {
+            components: [
+                {
+                    name: 'field1',
+                    type: 'string',
+                },
+                {
+                    name: 'field2',
+                    type: 'uint',
+                },
+            ],
+            name: 'Tuple',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateArraysNestedInTuples: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    name: 'field',
+                    type: 'uint[]',
+                },
+            ],
+            name: 'Tuple1',
+            type: 'tuple',
+        },
+        {
+            components: [
+                {
+                    name: 'field',
+                    type: 'uint[]',
+                },
+                {
+                    name: 'extraField',
+                    type: 'string',
+                },
+            ],
+            name: 'Tuple2',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateTuplesNestedInTuples: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            components: [
+                {
+                    components: [
+                        {
+                            name: 'nestedField',
+                            type: 'string',
+                        },
+                    ],
+                    name: 'field',
+                    type: 'tuple',
+                },
+            ],
+            name: 'Tuple1',
+            type: 'tuple',
+        },
+        {
+            components: [
+                {
+                    components: [
+                        {
+                            name: 'nestedField',
+                            type: 'string',
+                        },
+                    ],
+                    name: 'field',
+                    type: 'tuple',
+                },
+                {
+                    name: 'extraField',
+                    type: 'string',
+                },
+            ],
+            name: 'Tuple1',
+            type: 'tuple',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const duplicateTwoDimensionalArrays: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'array1',
+            type: 'string[][]',
+        },
+        {
+            name: 'array2',
+            type: 'string[][]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const arrayElementsDuplicatedAsSeparateParameter: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'stringArray',
+            type: 'string[]',
+        },
+        {
+            name: 'string',
+            type: 'string',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const arrayElementsDuplicatedAsTupleFields: MethodAbi = {
+    constant: false,
+    inputs: [
+        {
+            name: 'uint8Array',
+            type: 'uint8[]',
+        },
+        {
+            components: [
+                {
+                    name: 'uint',
+                    type: 'uint',
+                },
+            ],
+            name: 'uintTuple',
+            type: 'tuple[]',
+        },
+    ],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
diff --git a/packages/utils/test/abi_encoder/abi_samples/return_value_abis.ts b/packages/utils/test/abi_encoder/abi_samples/return_value_abis.ts
new file mode 100644
index 000000000..ac2124011
--- /dev/null
+++ b/packages/utils/test/abi_encoder/abi_samples/return_value_abis.ts
@@ -0,0 +1,99 @@
+/* tslint:disable max-file-line-count */
+import { MethodAbi } from 'ethereum-types';
+
+export const noReturnValues: MethodAbi = {
+    constant: false,
+    inputs: [],
+    name: 'simpleFunction',
+    outputs: [],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const singleStaticReturnValue: MethodAbi = {
+    constant: false,
+    inputs: [],
+    name: 'simpleFunction',
+    outputs: [
+        {
+            name: 'Bytes4',
+            type: 'bytes4',
+        },
+    ],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const multipleStaticReturnValues: MethodAbi = {
+    constant: false,
+    inputs: [],
+    name: 'simpleFunction',
+    outputs: [
+        {
+            name: 'val1',
+            type: 'bytes4',
+        },
+        {
+            name: 'val2',
+            type: 'bytes4',
+        },
+    ],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const singleDynamicReturnValue: MethodAbi = {
+    constant: false,
+    inputs: [],
+    name: 'simpleFunction',
+    outputs: [
+        {
+            name: 'val',
+            type: 'bytes',
+        },
+    ],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const multipleDynamicReturnValues: MethodAbi = {
+    constant: false,
+    inputs: [],
+    name: 'simpleFunction',
+    outputs: [
+        {
+            name: 'val1',
+            type: 'bytes',
+        },
+        {
+            name: 'val2',
+            type: 'bytes',
+        },
+    ],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
+
+export const mixedStaticAndDynamicReturnValues: MethodAbi = {
+    constant: false,
+    inputs: [],
+    name: 'simpleFunction',
+    outputs: [
+        {
+            name: 'val1',
+            type: 'bytes4',
+        },
+        {
+            name: 'val2',
+            type: 'bytes',
+        },
+    ],
+    payable: false,
+    stateMutability: 'nonpayable',
+    type: 'function',
+};
diff --git a/packages/utils/test/abi_encoder/evm_data_types_test.ts b/packages/utils/test/abi_encoder/evm_data_types_test.ts
new file mode 100644
index 000000000..9ef80a560
--- /dev/null
+++ b/packages/utils/test/abi_encoder/evm_data_types_test.ts
@@ -0,0 +1,1007 @@
+/* tslint:disable max-file-line-count */
+import * as chai from 'chai';
+import * as ethUtil from 'ethereumjs-util';
+import 'mocha';
+
+import { AbiEncoder, BigNumber } from '../../src/';
+import { chaiSetup } from '../utils/chai_setup';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
+    const encodingRules: AbiEncoder.EncodingRules = { optimize: false }; // optimizer is tested separately.
+    describe('Array', () => {
+        it('Fixed size; Static elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'int[2]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const args = [new BigNumber(5), new BigNumber(6)];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Dynamic size; Static elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'int[]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const args = [new BigNumber(5), new BigNumber(6)];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Fixed size; Dynamic elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'string[2]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const args = ['Hello', 'world'];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005776f726c64000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Dynamic size; Dynamic elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'string[]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const args = ['Hello', 'world'];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005776f726c64000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Dynamic Size; Multidimensional; Dynamic Elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'bytes[][]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const array1 = ['0x01020304', '0x05060708', '0x09101112'];
+            const array2 = ['0x10111213', '0x14151617'];
+            const array3 = ['0x18192021'];
+            const args = [array1, array2, array3];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x0000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000001a000000000000000000000000000000000000000000000000000000000000002800000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000040102030400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000405060708000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004091011120000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000041011121300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000414151617000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000041819202100000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Dynamic Size; Multidimensional; Static Elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'bytes4[][]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const array1 = ['0x01020304', '0x05060708', '0x09101112'];
+            const array2 = ['0x10111213', '0x14151617'];
+            const array3 = ['0x18192021'];
+            const args = [array1, array2, array3];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x0000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000000301020304000000000000000000000000000000000000000000000000000000000506070800000000000000000000000000000000000000000000000000000000091011120000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000021011121300000000000000000000000000000000000000000000000000000000141516170000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000011819202100000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Static Size; Multidimensional; Static Elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'bytes4[3][2]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const array1 = ['0x01020304', '0x05060708', '0x09101112'];
+            const array2 = ['0x10111213', '0x14151617', '0x18192021'];
+            const args = [array1, array2];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x010203040000000000000000000000000000000000000000000000000000000005060708000000000000000000000000000000000000000000000000000000000910111200000000000000000000000000000000000000000000000000000000101112130000000000000000000000000000000000000000000000000000000014151617000000000000000000000000000000000000000000000000000000001819202100000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Static Size; Multidimensional; Dynamic Elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'bytes[3][2]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const array1 = ['0x01020304', '0x05060708', '0x09101112'];
+            const array2 = ['0x10111213', '0x14151617', '0x18192021'];
+            const args = [array1, array2];
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000160000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000000401020304000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004050607080000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000040910111200000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000000410111213000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004141516170000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000041819202100000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Static size; Too Few Elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'string[3]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const args = ['Hello', 'world'];
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw('Expected array of 3 elements, but got array of length 2');
+        });
+        it('Static size; Too Many Elements', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'string[1]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const args = ['Hello', 'world'];
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw('Expected array of 1 elements, but got array of length 2');
+        });
+        it('Element Type Mismatch', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'testArray', type: 'uint[]' };
+            const dataType = new AbiEncoder.Array(testDataItem);
+            // Construct args to be encoded
+            const args = [new BigNumber(1), 'Bad Argument'];
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+    });
+
+    describe('Tuple', () => {
+        it('Static elements only', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field_1', type: 'int32' }, { name: 'field_2', type: 'bool' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const args = { field_1: new BigNumber(-5), field_2: true };
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0xfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffb0000000000000000000000000000000000000000000000000000000000000001';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodingRules: AbiEncoder.DecodingRules = { structsAsObjects: true };
+            const decodedArgs = dataType.decode(encodedArgs, decodingRules);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Dynamic elements only', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field_1', type: 'string' }, { name: 'field_2', type: 'bytes' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const args = { field_1: 'Hello, World!', field_2: '0xabcdef0123456789' };
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000d48656c6c6f2c20576f726c6421000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000008abcdef0123456789000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodingRules: AbiEncoder.DecodingRules = { structsAsObjects: true };
+            const decodedArgs = dataType.decode(encodedArgs, decodingRules);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Nested Static Array', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field', type: 'uint[2]' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const args = { field: [new BigNumber(1), new BigNumber(2)] };
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodingRules: AbiEncoder.DecodingRules = { structsAsObjects: true };
+            const decodedArgs = dataType.decode(encodedArgs, decodingRules);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Nested Dynamic Array', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field', type: 'uint[]' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const args = { field: [new BigNumber(1), new BigNumber(2)] };
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000002';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodingRules: AbiEncoder.DecodingRules = { structsAsObjects: true };
+            const decodedArgs = dataType.decode(encodedArgs, decodingRules);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Nested Static Multidimensional Array', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field', type: 'bytes4[2][2]' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const array1 = ['0x01020304', '0x05060708'];
+            const array2 = ['0x09101112', '0x13141516'];
+            const args = { field: [array1, array2] };
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x0102030400000000000000000000000000000000000000000000000000000000050607080000000000000000000000000000000000000000000000000000000009101112000000000000000000000000000000000000000000000000000000001314151600000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodingRules: AbiEncoder.DecodingRules = { structsAsObjects: true };
+            const decodedArgs = dataType.decode(encodedArgs, decodingRules);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Nested Dynamic Multidimensional Array', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field', type: 'bytes[2][2]' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const array1 = ['0x01020304', '0x05060708'];
+            const array2 = ['0x09101112', '0x13141516'];
+            const args = { field: [array1, array2] };
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000004010203040000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000040506070800000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000004091011120000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000041314151600000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodingRules: AbiEncoder.DecodingRules = { structsAsObjects: true };
+            const decodedArgs = dataType.decode(encodedArgs, decodingRules);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Static and dynamic elements mixed', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [
+                    { name: 'field_1', type: 'int32' },
+                    { name: 'field_2', type: 'string' },
+                    { name: 'field_3', type: 'bool' },
+                    { name: 'field_4', type: 'bytes' },
+                ],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const args = {
+                field_1: new BigNumber(-5),
+                field_2: 'Hello, World!',
+                field_3: true,
+                field_4: '0xabcdef0123456789',
+            };
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '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';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodingRules: AbiEncoder.DecodingRules = { structsAsObjects: true };
+            const decodedArgs = dataType.decode(encodedArgs, decodingRules);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Missing Key', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field_1', type: 'int32' }, { name: 'field_2', type: 'bool' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const args = { field_1: new BigNumber(-5) };
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw('Could not assign tuple to object: missing keys field_2');
+        });
+        it('Bad Key', async () => {
+            // Create DataType object
+            const testDataItem = {
+                name: 'Tuple',
+                type: 'tuple',
+                components: [{ name: 'field_1', type: 'int32' }, { name: 'field_2', type: 'bool' }],
+            };
+            const dataType = new AbiEncoder.Tuple(testDataItem);
+            // Construct args to be encoded
+            const args = { unknown_field: new BigNumber(-5) };
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw("Could not assign tuple to object: unrecognized key 'unknown_field' in object Tuple");
+        });
+    });
+
+    describe('Address', () => {
+        it('Valid Address', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Address', type: 'address' };
+            const dataType = new AbiEncoder.Address(testDataItem);
+            // Construct args to be encoded
+            const args = '0xe41d2489571d322189246dafa5ebde1f4699f498';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x000000000000000000000000e41d2489571d322189246dafa5ebde1f4699f498';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Invalid Address - input is not valid hex', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Address', type: 'address' };
+            const dataType = new AbiEncoder.Address(testDataItem);
+            // Construct args to be encoded
+            const args = 'e4';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw(`Invalid address: '${args}'`);
+        });
+        it('Invalid Address - input is not 20 bytes', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Address', type: 'address' };
+            const dataType = new AbiEncoder.Address(testDataItem);
+            // Construct args to be encoded
+            const args = '0xe4';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw(`Invalid address: '${args}'`);
+        });
+    });
+
+    describe('Bool', () => {
+        it('True', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Boolean', type: 'bool' };
+            const dataType = new AbiEncoder.Bool(testDataItem);
+            // Construct args to be encoded
+            const args = true;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0000000000000000000000000000000000000000000000000000000000000001';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('False', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Boolean', type: 'bool' };
+            const dataType = new AbiEncoder.Bool(testDataItem);
+            // Construct args to be encoded
+            const args = false;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0000000000000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+    });
+
+    describe('Integer', () => {
+        /* tslint:disable custom-no-magic-numbers */
+        const max256BitInteger = new BigNumber(2).pow(255).minus(1);
+        const min256BitInteger = new BigNumber(2).pow(255).times(-1);
+        const max32BitInteger = new BigNumber(2).pow(31).minus(1);
+        const min32BitInteger = new BigNumber(2).pow(31).times(-1);
+        /* tslint:enable custom-no-magic-numbers */
+
+        it('Int256 - Positive Base Case', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (256)', type: 'int' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = new BigNumber(1);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0000000000000000000000000000000000000000000000000000000000000001';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int256 - Negative Base Case', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (256)', type: 'int' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = new BigNumber(-1);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int256 - Positive Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (256)', type: 'int' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = max256BitInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int256 - Negative Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (256)', type: 'int' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = min256BitInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = `0x8000000000000000000000000000000000000000000000000000000000000000`;
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int256 - Value too large', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (256)', type: 'int' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = max256BitInteger.plus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+        it('Int256 - Value too small', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (256)', type: 'int' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = min256BitInteger.minus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+        it('Int32 - Positive Base Case', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (32)', type: 'int32' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = new BigNumber(1);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0000000000000000000000000000000000000000000000000000000000000001';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int32 - Negative Base Case', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (32)', type: 'int32' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = new BigNumber(-1);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int32 - Positive Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (32)', type: 'int32' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = max32BitInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x000000000000000000000000000000000000000000000000000000007fffffff';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int32 - Negative Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (32)', type: 'int32' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = min32BitInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = `0xffffffffffffffffffffffffffffffffffffffffffffffffffffffff80000000`;
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Int32 - Value too large', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (32)', type: 'int32' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = max32BitInteger.plus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+        it('Int32 - Value too small', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Integer (32)', type: 'int32' };
+            const dataType = new AbiEncoder.Int(testDataItem);
+            // Construct args to be encoded
+            const args = min32BitInteger.minus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+    });
+
+    describe('Unsigned Integer', () => {
+        /* tslint:disable custom-no-magic-numbers */
+        const max256BitUnsignedInteger = new BigNumber(2).pow(256).minus(1);
+        const min256BitUnsignedInteger = new BigNumber(0);
+        const max32BitUnsignedInteger = new BigNumber(2).pow(32).minus(1);
+        const min32BitUnsignedInteger = new BigNumber(0);
+        /* tslint:enable custom-no-magic-numbers */
+
+        it('UInt256 - Positive Base Case', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (256)', type: 'uint' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = new BigNumber(1);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0000000000000000000000000000000000000000000000000000000000000001';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('UInt256 - Positive Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (256)', type: 'uint' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = max256BitUnsignedInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('UInt256 - Zero Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (256)', type: 'uint' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = min256BitUnsignedInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = `0x0000000000000000000000000000000000000000000000000000000000000000`;
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('UInt256 - Value too large', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (256)', type: 'uint' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = max256BitUnsignedInteger.plus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+        it('UInt256 - Value too small', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (256)', type: 'uint' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = min256BitUnsignedInteger.minus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+        it('UInt32 - Positive Base Case', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (32)', type: 'uint32' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = new BigNumber(1);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0000000000000000000000000000000000000000000000000000000000000001';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('UInt32 - Positive Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (32)', type: 'uint32' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = max32BitUnsignedInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x00000000000000000000000000000000000000000000000000000000ffffffff';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('UInt32 - Zero Value', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (32)', type: 'uint32' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = min32BitUnsignedInteger;
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = `0x0000000000000000000000000000000000000000000000000000000000000000`;
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('UInt32 - Value too large', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (32)', type: 'uint32' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = max32BitUnsignedInteger.plus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+        it('UInt32 - Value too small', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Unsigned Integer (32)', type: 'uint32' };
+            const dataType = new AbiEncoder.UInt(testDataItem);
+            // Construct args to be encoded
+            const args = min32BitUnsignedInteger.minus(1);
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw();
+        });
+    });
+
+    describe('Static Bytes', () => {
+        it('Single Byte (byte)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Byte', type: 'byte' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x05';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0500000000000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Single Byte (bytes1)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes1', type: 'bytes1' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x05';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0500000000000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('4 Bytes (bytes4)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes4', type: 'bytes4' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x00010203';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0001020300000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('4 Bytes (bytes4); Encoder must pad input', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes4', type: 'bytes4' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const args = '0x1a18';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x1a18000000000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            const paddedArgs = '0x1a180000';
+            expect(decodedArgs).to.be.deep.equal(paddedArgs);
+        });
+        it('32 Bytes (bytes32)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes32', type: 'bytes32' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x0001020304050607080911121314151617181920212223242526272829303132';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x0001020304050607080911121314151617181920212223242526272829303132';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('32 Bytes (bytes32); Encoder must pad input', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes32', type: 'bytes32' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const args = '0x1a18bf61';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs = '0x1a18bf6100000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            const paddedArgs = '0x1a18bf6100000000000000000000000000000000000000000000000000000000';
+            expect(decodedArgs).to.be.deep.equal(paddedArgs);
+        });
+        it('Should throw when pass in too many bytes (bytes4)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes4', type: 'bytes4' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x0102030405';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw(
+                'Tried to assign 0x0102030405 (5 bytes), which exceeds max bytes that can be stored in a bytes4',
+            );
+        });
+        it('Should throw when pass in too many bytes (bytes32)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes32', type: 'bytes32' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x010203040506070809101112131415161718192021222324252627282930313233';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw(
+                'Tried to assign 0x010203040506070809101112131415161718192021222324252627282930313233 (33 bytes), which exceeds max bytes that can be stored in a bytes32',
+            );
+        });
+        it('Should throw when pass in bad hex (no 0x prefix)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes32', type: 'bytes32' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0102030405060708091011121314151617181920212223242526272829303132';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw("Tried to encode non-hex value. Value must inlcude '0x' prefix.");
+        });
+        it('Should throw when pass in bad hex (include a half-byte)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes32', type: 'bytes32' };
+            const dataType = new AbiEncoder.StaticBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x010';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw('Tried to assign 0x010, which is contains a half-byte. Use full bytes only.');
+        });
+    });
+
+    describe('Dynamic Bytes', () => {
+        it('Fits into one EVM word', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Dynamic Bytes', type: 'bytes' };
+            const dataType = new AbiEncoder.DynamicBytes(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const args = '0x1a18bf61';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000041a18bf6100000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Spans multiple EVM words', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Dynamic Bytes', type: 'bytes' };
+            const dataType = new AbiEncoder.DynamicBytes(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const bytesLength = 40;
+            const args = '0x' + '61'.repeat(bytesLength);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x000000000000000000000000000000000000000000000000000000000000002861616161616161616161616161616161616161616161616161616161616161616161616161616161000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Input as Buffer', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Dynamic Bytes', type: 'bytes' };
+            const dataType = new AbiEncoder.DynamicBytes(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const args = '0x1a18bf61';
+            const argsAsBuffer = ethUtil.toBuffer(args);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(argsAsBuffer);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000041a18bf6100000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Should throw when pass in bad hex (no 0x prefix)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes', type: 'bytes' };
+            const dataType = new AbiEncoder.DynamicBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '01';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw("Tried to encode non-hex value. Value must inlcude '0x' prefix.");
+        });
+        it('Should throw when pass in bad hex (include a half-byte)', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'Static Bytes', type: 'bytes' };
+            const dataType = new AbiEncoder.DynamicBytes(testDataItem);
+            // Construct args to be encoded
+            const args = '0x010';
+            // Encode Args and validate result
+            expect(() => {
+                dataType.encode(args, encodingRules);
+            }).to.throw('Tried to assign 0x010, which is contains a half-byte. Use full bytes only.');
+        });
+    });
+
+    describe('String', () => {
+        it('Fits into one EVM word', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'String', type: 'string' };
+            const dataType = new AbiEncoder.String(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const args = 'five';
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x00000000000000000000000000000000000000000000000000000000000000046669766500000000000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('Spans multiple EVM words', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'String', type: 'string' };
+            const dataType = new AbiEncoder.String(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const bytesLength = 40;
+            const args = 'a'.repeat(bytesLength);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x000000000000000000000000000000000000000000000000000000000000002861616161616161616161616161616161616161616161616161616161616161616161616161616161000000000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+        it('String that begins with 0x prefix', async () => {
+            // Create DataType object
+            const testDataItem = { name: 'String', type: 'string' };
+            const dataType = new AbiEncoder.String(testDataItem);
+            // Construct args to be encoded
+            // Note: There will be padding because this is a bytes32 but we are only passing in 4 bytes.
+            const strLength = 40;
+            const args = '0x' + 'a'.repeat(strLength);
+            // Encode Args and validate result
+            const encodedArgs = dataType.encode(args, encodingRules);
+            const expectedEncodedArgs =
+                '0x000000000000000000000000000000000000000000000000000000000000002a30786161616161616161616161616161616161616161616161616161616161616161616161616161616100000000000000000000000000000000000000000000';
+            expect(encodedArgs).to.be.equal(expectedEncodedArgs);
+            // Decode Encoded Args and validate result
+            const decodedArgs = dataType.decode(encodedArgs);
+            expect(decodedArgs).to.be.deep.equal(args);
+        });
+    });
+});
diff --git a/packages/utils/test/abi_encoder/methods_test.ts b/packages/utils/test/abi_encoder/methods_test.ts
new file mode 100644
index 000000000..837020883
--- /dev/null
+++ b/packages/utils/test/abi_encoder/methods_test.ts
@@ -0,0 +1,366 @@
+import * as chai from 'chai';
+import 'mocha';
+
+import { AbiEncoder, BigNumber } from '../../src/';
+import { chaiSetup } from '../utils/chai_setup';
+
+import * as AbiSamples from './abi_samples/method_abis';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('ABI Encoder: Method Encoding / Decoding', () => {
+    const encodingRules: AbiEncoder.EncodingRules = { optimize: false }; // optimizer is tested separately.
+    it('Types with default widths', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.typesWithDefaultWidthsAbi);
+        const args = [new BigNumber(1), new BigNumber(-1), '0x56', [new BigNumber(1)], [new BigNumber(-1)], ['0x56']];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x09f2b0c30000000000000000000000000000000000000000000000000000000000000001ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff560000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00000000000000000000000000000000000000000000000000000000000000015600000000000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Array of Static Tuples (Array has defined length)', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.arrayOfStaticTuplesWithDefinedLengthAbi);
+        let value = 0;
+        const arrayOfTuples = [];
+        const arrayOfTuplesLength = 8;
+        for (let i = 0; i < arrayOfTuplesLength; ++i) {
+            arrayOfTuples.push([new BigNumber(++value), new BigNumber(++value)]);
+        }
+        const args = [arrayOfTuples];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x9eb20969000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000700000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000010';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Array of Static Tuples (Array has dynamic length)', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.arrayOfStaticTuplesWithDynamicLengthAbi);
+        let value = 0;
+        const arrayOfTuples = [];
+        const arrayOfTuplesLength = 8;
+        for (let i = 0; i < arrayOfTuplesLength; ++i) {
+            arrayOfTuples.push([new BigNumber(++value), new BigNumber(++value)]);
+        }
+        const args = [arrayOfTuples];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x63275d6e00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000700000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000010';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Array of Dynamic Tuples (Array has defined length)', async () => {
+        // Generate Calldata
+        const method = new AbiEncoder.Method(AbiSamples.arrayOfDynamicTuplesWithDefinedLengthAbi);
+        let value = 0;
+        const arrayOfTuples = [];
+        const arrayOfTuplesLength = 8;
+        for (let i = 0; i < arrayOfTuplesLength; ++i) {
+            arrayOfTuples.push([new BigNumber(++value), new BigNumber(++value).toString()]);
+        }
+        const args = [arrayOfTuples];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0xdeedb00f00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000018000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000280000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000003800000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000048000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000013400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000500000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000001360000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000138000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023130000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023134000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023136000000000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Array of Dynamic Tuples (Array has dynamic length)', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.arrayOfDynamicTuplesWithUndefinedLengthAbi);
+        let value = 0;
+        const arrayOfTuples = [];
+        const arrayOfTuplesLength = 8;
+        for (let i = 0; i < arrayOfTuplesLength; ++i) {
+            arrayOfTuples.push([new BigNumber(++value), new BigNumber(++value).toString()]);
+        }
+        const args = [arrayOfTuples];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x60c847fb000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000018000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000280000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000003800000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000048000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000013400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000500000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000001360000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000138000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023130000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023134000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023136000000000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Multidimensional Arrays / Static Members', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.multiDimensionalArraysStaticTypeAbi);
+        // Eight 3-dimensional arrays of uint8[2][2][2]
+        let value = 0;
+        const args = [];
+        const argsLength = 8;
+        for (let i = 0; i < argsLength; ++i) {
+            args.push([
+                [[new BigNumber(++value), new BigNumber(++value)], [new BigNumber(++value), new BigNumber(++value)]],
+                [[new BigNumber(++value), new BigNumber(++value)], [new BigNumber(++value), new BigNumber(++value)]],
+            ]);
+        }
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0xc2f47d6f00000000000000000000000000000000000000000000000000000000000001e00000000000000000000000000000000000000000000000000000000000000480000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000009600000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000d400000000000000000000000000000000000000000000000000000000000000e600000000000000000000000000000000000000000000000000000000000000039000000000000000000000000000000000000000000000000000000000000003a000000000000000000000000000000000000000000000000000000000000003b000000000000000000000000000000000000000000000000000000000000003c000000000000000000000000000000000000000000000000000000000000003d000000000000000000000000000000000000000000000000000000000000003e000000000000000000000000000000000000000000000000000000000000003f00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000001600000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000001600000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000110000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000130000000000000000000000000000000000000000000000000000000000000014000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000150000000000000000000000000000000000000000000000000000000000000016000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000170000000000000000000000000000000000000000000000000000000000000018000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000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+        expect(calldata).to.be.equal(expectedCalldata);
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Multidimensional Arrays / Dynamic Members', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.multiDimensionalArraysDynamicTypeAbi);
+        // Eight 3-dimensional arrays of string[2][2][2]
+        let value = 0;
+        const args = [];
+        const argsLength = 4;
+        for (let i = 0; i < argsLength; ++i) {
+            args.push([
+                [
+                    [new BigNumber(++value).toString(), new BigNumber(++value).toString()],
+                    [new BigNumber(++value).toString(), new BigNumber(++value).toString()],
+                ],
+                [
+                    [new BigNumber(++value).toString(), new BigNumber(++value).toString()],
+                    [new BigNumber(++value).toString(), new BigNumber(++value).toString()],
+                ],
+            ]);
+        }
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x81534ebd0000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000052000000000000000000000000000000000000000000000000000000000000009a00000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000026000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000013100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000001330000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000013400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000135000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001360000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000013700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000138000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000026000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000013900000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000231300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000002313100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000023132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000231330000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002313400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000023135000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000231360000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000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+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Fixed Length Array / Dynamic Members', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.staticArrayDynamicMembersAbi);
+        const args = [['Brave', 'New', 'World']];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x243a6e6e0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Fixed Length Array / Dynamic Members', async () => {
+        // Generaet calldata
+        const method = new AbiEncoder.Method(AbiSamples.staticArrayDynamicMembersAbi);
+        const args = [['Brave', 'New', 'World']];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x243a6e6e0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Unfixed Length Array / Dynamic Members ABI', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.dynamicArrayDynamicMembersAbi);
+        const args = [['Brave', 'New', 'World']];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x13e751a900000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Unfixed Length Array / Static Members ABI', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.dynamicArrayStaticMembersAbi);
+        const args = [[new BigNumber(127), new BigNumber(14), new BigNumber(54)]];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x4fc8a83300000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000007f000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000036';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Fixed Length Array / Static Members ABI', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.staticArrayAbi);
+        const args = [[new BigNumber(127), new BigNumber(14), new BigNumber(54)]];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0xf68ade72000000000000000000000000000000000000000000000000000000000000007f000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000036';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Array ABI', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(AbiSamples.stringAbi);
+        const args = [['five', 'six', 'seven']];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x13e751a900000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000046669766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000373697800000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005736576656e000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Static Tuple', async () => {
+        // Generate calldata
+        // This is dynamic because it has dynamic members
+        const method = new AbiEncoder.Method(AbiSamples.staticTupleAbi);
+        const args = [[new BigNumber(5), new BigNumber(10), new BigNumber(15), false]];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0xa9125e150000000000000000000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Dynamic Tuple (Array input)', async () => {
+        // Generate calldata
+        // This is dynamic because it has dynamic members
+        const method = new AbiEncoder.Method(AbiSamples.dynamicTupleAbi);
+        const args = [[new BigNumber(5), 'five']];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x5b998f3500000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000046669766500000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Dynamic Tuple (Object input)', async () => {
+        // Generate Calldata
+        // This is dynamic because it has dynamic members
+        const method = new AbiEncoder.Method(AbiSamples.dynamicTupleAbi);
+        const args = [[new BigNumber(5), 'five']];
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x5b998f3500000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000046669766500000000000000000000000000000000000000000000000000000000';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Large, Flat ABI', async () => {
+        // Construct calldata
+        const method = new AbiEncoder.Method(AbiSamples.largeFlatAbi);
+        const args = [
+            new BigNumber(256745454),
+            new BigNumber(-256745454),
+            new BigNumber(434244),
+            '0x43',
+            '0x0001020304050607080911121314151617181920212223242526272829303132',
+            '0x0001020304050607080911121314151617181920212223242526272829303132080911121314151617181920212223242526272829303132',
+            'Little peter piper piped a piping pepper pot',
+            '0xe41d2489571d322189246dafa5ebde1f4699f498',
+            true,
+        ];
+        // Validate calldata
+        const calldata = method.encode(args, encodingRules);
+        const expectedCalldata =
+            '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';
+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata);
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+    it('Large, Nested ABI', async () => {
+        // Construct Calldata
+        const method = new AbiEncoder.Method(AbiSamples.largeNestedAbi);
+        const someStaticArray = [new BigNumber(127), new BigNumber(14), new BigNumber(54)];
+        const someStaticArrayWithDynamicMembers = [
+            'the little piping piper piped a piping pipper papper',
+            'the kid knows how to write poems, what can I say -- I guess theres a lot I could say to try to fill this line with a lot of text.',
+        ];
+        const someDynamicArrayWithDynamicMembers = [
+            '0x38745637834987324827439287423897238947239847',
+            '0x7283472398237423984723984729847248927498748974284728947239487498749847874329423743492347329847239842374892374892374892347238947289478947489374289472894738942749823743298742389472389473289472389437249823749823742893472398',
+            '0x283473298473248923749238742398742398472894729843278942374982374892374892743982',
+        ];
+        const some2DArray = [
+            [
+                'some string',
+                'some another string',
+                'there are just too many stringsup in',
+                'here',
+                'yall ghonna make me lose my mind',
+            ],
+            [
+                'the little piping piper piped a piping pipper papper',
+                'the kid knows how to write poems, what can I say -- I guess theres a lot I could say to try to fill this line with a lot of text.',
+            ],
+            [],
+        ];
+        const someTuple = {
+            someUint32: new BigNumber(4037824789),
+            someStr:
+                'the kid knows how to write poems, what can I say -- I guess theres a lot I could say to try to fill this line with a lot of text.',
+        };
+        const someTupleWithDynamicTypes = {
+            someUint: new BigNumber(4024789),
+            someStr: 'akdhjasjkdhasjkldshdjahdkjsahdajksdhsajkdhsajkdhadjkashdjksadhajkdhsajkdhsadjk',
+            someBytes: '0x29384723894723843743289742389472398473289472348927489274894738427428947389facdea',
+            someAddress: '0xe41d2489571d322189246dafa5ebde1f4699f498',
+        };
+        const someTupleWithDynamicTypes2 = {
+            someUint: new BigNumber(9024789),
+            someStr: 'ksdhsajkdhsajkdhadjkashdjksadhajkdhsajkdhsadjkakdhjasjkdhasjkldshdjahdkjsahdaj',
+            someBytes: '0x29384723894398473289472348927489272384374328974238947274894738427428947389facde1',
+            someAddress: '0x746dafa5ebde1f4699f4981d3221892e41d24895',
+        };
+        const someTupleWithDynamicTypes3 = {
+            someUint: new BigNumber(1024789),
+            someStr: 'sdhsajkdhsajkdhadjkashdjakdhjasjkdhasjkldshdjahdkjsahdajkksadhajkdhsajkdhsadjk',
+            someBytes: '0x38947238437432829384729742389472398473289472348927489274894738427428947389facdef',
+            someAddress: '0x89571d322189e415ebde1f4699f498d24246dafa',
+        };
+        const someArrayOfTuplesWithDynamicTypes = [someTupleWithDynamicTypes2, someTupleWithDynamicTypes3];
+        const args = {
+            someStaticArray,
+            someStaticArrayWithDynamicMembers,
+            someDynamicArrayWithDynamicMembers,
+            some2DArray,
+            someTuple,
+            someTupleWithDynamicTypes,
+            someArrayOfTuplesWithDynamicTypes,
+        };
+        const calldata = method.encode(args, encodingRules);
+        // Validate calldata
+        const expectedCalldata =
+            '0x4b49031c000000000000000000000000000000000000000000000000000000000000007f000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000036000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000002800000000000000000000000000000000000000000000000000000000000000440000000000000000000000000000000000000000000000000000000000000088000000000000000000000000000000000000000000000000000000000000009800000000000000000000000000000000000000000000000000000000000000ae0000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000034746865206c6974746c6520706970696e67207069706572207069706564206120706970696e6720706970706572207061707065720000000000000000000000000000000000000000000000000000000000000000000000000000000000000081746865206b6964206b6e6f777320686f7720746f20777269746520706f656d732c20776861742063616e204920736179202d2d2049206775657373207468657265732061206c6f74204920636f756c642073617920746f2074727920746f2066696c6c2074686973206c696e6520776974682061206c6f74206f6620746578742e000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000014000000000000000000000000000000000000000000000000000000000000000163874563783498732482743928742389723894723984700000000000000000000000000000000000000000000000000000000000000000000000000000000006e72834723982374239847239847298472489274987489742847289472394874987498478743294237434923473298472398423748923748923748923472389472894789474893742894728947389427498237432987423894723894732894723894372498237498237428934723980000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000027283473298473248923749238742398742398472894729843278942374982374892374892743982000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000002800000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000000500000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000018000000000000000000000000000000000000000000000000000000000000001c0000000000000000000000000000000000000000000000000000000000000000b736f6d6520737472696e670000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000013736f6d6520616e6f7468657220737472696e67000000000000000000000000000000000000000000000000000000000000000000000000000000000000000024746865726520617265206a75737420746f6f206d616e7920737472696e6773757020696e0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000046865726500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002079616c6c2067686f6e6e61206d616b65206d65206c6f7365206d79206d696e640000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000034746865206c6974746c6520706970696e67207069706572207069706564206120706970696e6720706970706572207061707065720000000000000000000000000000000000000000000000000000000000000000000000000000000000000081746865206b6964206b6e6f777320686f7720746f20777269746520706f656d732c20776861742063616e204920736179202d2d2049206775657373207468657265732061206c6f74204920636f756c642073617920746f2074727920746f2066696c6c2074686973206c696e6520776974682061206c6f74206f6620746578742e00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f0ac511500000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000081746865206b6964206b6e6f777320686f7720746f20777269746520706f656d732c20776861742063616e204920736179202d2d2049206775657373207468657265732061206c6f74204920636f756c642073617920746f2074727920746f2066696c6c2074686973206c696e6520776974682061206c6f74206f6620746578742e0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003d69d50000000000000000000000000000000000000000000000000000000000000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+        expect(calldata).to.be.equal(expectedCalldata);
+        // Validate decoding
+        const decodedValue = method.decode(calldata, { structsAsObjects: true });
+        expect(decodedValue).to.be.deep.equal(args);
+    });
+});
diff --git a/packages/utils/test/abi_encoder/optimizer_test.ts b/packages/utils/test/abi_encoder/optimizer_test.ts
new file mode 100644
index 000000000..18aa6549a
--- /dev/null
+++ b/packages/utils/test/abi_encoder/optimizer_test.ts
@@ -0,0 +1,262 @@
+import * as chai from 'chai';
+import 'mocha';
+
+import { AbiEncoder, BigNumber } from '../../src/';
+import { chaiSetup } from '../utils/chai_setup';
+
+import * as OptimizedAbis from './abi_samples/optimizer_abis';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
+    const encodingRules: AbiEncoder.EncodingRules = { optimize: true };
+    it('Duplicate Dynamic Arrays with Static Elements', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateDynamicArraysWithStaticElements);
+        const array1 = [new BigNumber(100), new BigNumber(150)];
+        const array2 = array1;
+        const args = [array1, array2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x7221063300000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000640000000000000000000000000000000000000000000000000000000000000096';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Dynamic Arrays with Dynamic Elements', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateDynamicArraysWithDynamicElements);
+        const array1 = ['Hello', 'World'];
+        const array2 = array1;
+        const args = [array1, array2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0xbb4f12e300000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Static Arrays with Static Elements (should not optimize)', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateStaticArraysWithStaticElements);
+        const array1 = [new BigNumber(100), new BigNumber(150)];
+        const array2 = array1;
+        const args = [array1, array2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x7f8130430000000000000000000000000000000000000000000000000000000000000064000000000000000000000000000000000000000000000000000000000000009600000000000000000000000000000000000000000000000000000000000000640000000000000000000000000000000000000000000000000000000000000096';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        const unoptimizedCalldata = method.encode(args);
+        expect(optimizedCalldata).to.be.equal(unoptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Static Arrays with Dynamic Elements', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateStaticArraysWithDynamicElements);
+        const array1 = ['Hello', 'World'];
+        const array2 = array1;
+        const args = [array1, array2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x9fe31f8e0000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Array Elements (should optimize)', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateArrayElements);
+        const strings = ['Hello', 'World', 'Hello', 'World'];
+        const args = [strings];
+        // Validate calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x13e751a900000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000c0000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000c0000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Tuple Fields', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateTupleFields);
+        const tuple = ['Hello', 'Hello'];
+        const args = [tuple];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x16780a5e000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000548656c6c6f000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Strings', async () => {
+        // Description:
+        //   Two dynamic arrays with the same values.
+        //   In the optimized calldata, only one set of elements should be included.
+        //   Both arrays should point to this set.
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateStrings);
+        const args = ['Hello', 'Hello'];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x07370bfa00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000548656c6c6f000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Bytes', async () => {
+        // Description:
+        //   Two dynamic arrays with the same values.
+        //   In the optimized calldata, only one set of elements should be included.
+        //   Both arrays should point to this set.
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateBytes);
+        const value = '0x01020304050607080910111213141516171819202122232425262728293031323334353637383940';
+        const args = [value, value];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x6045e42900000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000002801020304050607080910111213141516171819202122232425262728293031323334353637383940000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Tuples', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateTuples);
+        const tuple1 = ['Hello, World!', new BigNumber(424234)];
+        const tuple2 = tuple1;
+        const args = [tuple1, tuple2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x564f826d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000006792a000000000000000000000000000000000000000000000000000000000000000d48656c6c6f2c20576f726c642100000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Fields Across Two Tuples', async () => {
+        // Description:
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateTuples);
+        const tuple1 = ['Hello, World!', new BigNumber(1)];
+        const tuple2 = [tuple1[0], new BigNumber(2)];
+        const args = [tuple1, tuple2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x564f826d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000d48656c6c6f2c20576f726c642100000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Arrays, Nested in Separate Tuples', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateArraysNestedInTuples);
+        const array = [new BigNumber(100), new BigNumber(150), new BigNumber(200)];
+        const tuple1 = [array];
+        const tuple2 = [array, 'extra argument to prevent exactly matching the tuples'];
+        const args = [tuple1, tuple2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x18970a9e000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000060000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000064000000000000000000000000000000000000000000000000000000000000009600000000000000000000000000000000000000000000000000000000000000c80000000000000000000000000000000000000000000000000000000000000035657874726120617267756d656e7420746f2070726576656e742065786163746c79206d61746368696e6720746865207475706c65730000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Tuples, Nested in Separate Tuples', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateTuplesNestedInTuples);
+        const nestedTuple = ['Hello, World!'];
+        const tuple1 = [nestedTuple];
+        const tuple2 = [nestedTuple, 'extra argument to prevent exactly matching the tuples'];
+        const args = [tuple1, tuple2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '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';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Two-Dimensional Arrays', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateTwoDimensionalArrays);
+        const twoDimArray1 = [['Hello', 'World'], ['Foo', 'Bar', 'Zaa']];
+        const twoDimArray2 = twoDimArray1;
+        const args = [twoDimArray1, twoDimArray2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, { optimize: false });
+        const expectedOptimizedCalldata =
+            '0x0d28c4f9000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000002c0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c640000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000003466f6f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003426172000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000035a61610000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c640000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000003466f6f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003426172000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000035a61610000000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Duplicate Array, Nested within Separate Two-Dimensional Arrays', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.duplicateTwoDimensionalArrays);
+        const twoDimArray1 = [['Hello', 'World'], ['Foo']];
+        const twoDimArray2 = [['Hello', 'World'], ['Bar']];
+        const args = [twoDimArray1, twoDimArray2];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x0d28c4f900000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000001200000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003466f6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c640000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000034261720000000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Array Elements Duplicated as Tuple Fields', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.arrayElementsDuplicatedAsTupleFields);
+        const array = [new BigNumber(100), new BigNumber(150), new BigNumber(200), new BigNumber(225)];
+        const tuple = [[array[0]], [array[1]], [array[2]], [array[3]]];
+        const args = [array, tuple];
+        // Validata calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0x5b5c78fd0000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000064000000000000000000000000000000000000000000000000000000000000009600000000000000000000000000000000000000000000000000000000000000c800000000000000000000000000000000000000000000000000000000000000e1';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+    it('Array Elements Duplicated as Separate Parameter', async () => {
+        // Generate calldata
+        const method = new AbiEncoder.Method(OptimizedAbis.arrayElementsDuplicatedAsSeparateParameter);
+        const array = ['Hello', 'Hello', 'Hello', 'World'];
+        const str = 'Hello';
+        const args = [array, str];
+        // Validate calldata
+        const optimizedCalldata = method.encode(args, encodingRules);
+        const expectedOptimizedCalldata =
+            '0xe0e0d34900000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000548656c6c6f000000000000000000000000000000000000000000000000000000';
+        expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
+        // Validate decoding
+        const decodedArgs = method.decode(optimizedCalldata);
+        expect(decodedArgs).to.be.deep.equal(args);
+    });
+});
diff --git a/packages/utils/test/abi_encoder/return_values_test.ts b/packages/utils/test/abi_encoder/return_values_test.ts
new file mode 100644
index 000000000..a8cdd6ca3
--- /dev/null
+++ b/packages/utils/test/abi_encoder/return_values_test.ts
@@ -0,0 +1,67 @@
+import * as chai from 'chai';
+import 'mocha';
+
+import { AbiEncoder } from '../../src/';
+import { chaiSetup } from '../utils/chai_setup';
+
+import * as ReturnValueAbis from './abi_samples/return_value_abis';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('ABI Encoder: Return Value Encoding/Decoding', () => {
+    const encodingRules: AbiEncoder.EncodingRules = { optimize: false }; // optimizer is tested separately.
+    it('No Return Value', async () => {
+        // Decode return value
+        const method = new AbiEncoder.Method(ReturnValueAbis.noReturnValues);
+        const returnValue = '0x';
+        const decodedReturnValue = method.decodeReturnValues(returnValue);
+        const expectedDecodedReturnValue: any[] = [];
+        expect(decodedReturnValue).to.be.deep.equal(expectedDecodedReturnValue);
+    });
+    it('Single static return value', async () => {
+        // Generate Return Value
+        const method = new AbiEncoder.Method(ReturnValueAbis.singleStaticReturnValue);
+        const returnValue = ['0x01020304'];
+        const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        // Validate decoded return value
+        expect(decodedReturnValue).to.be.deep.equal(returnValue);
+    });
+    it('Multiple static return values', async () => {
+        // Generate Return Value
+        const method = new AbiEncoder.Method(ReturnValueAbis.multipleStaticReturnValues);
+        const returnValue = ['0x01020304', '0x05060708'];
+        const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        // Validate decoded return value
+        expect(decodedReturnValue).to.be.deep.equal(returnValue);
+    });
+    it('Single dynamic return value', async () => {
+        // Generate Return Value
+        const method = new AbiEncoder.Method(ReturnValueAbis.singleDynamicReturnValue);
+        const returnValue = ['0x01020304'];
+        const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        // Validate decoded return value
+        expect(decodedReturnValue).to.be.deep.equal(returnValue);
+    });
+    it('Multiple dynamic return values', async () => {
+        // Generate Return Value
+        const method = new AbiEncoder.Method(ReturnValueAbis.multipleDynamicReturnValues);
+        const returnValue = ['0x01020304', '0x05060708'];
+        const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        // Validate decoded return value
+        expect(decodedReturnValue).to.be.deep.equal(returnValue);
+    });
+    it('Mixed static/dynamic return values', async () => {
+        // Generate Return Value
+        const method = new AbiEncoder.Method(ReturnValueAbis.mixedStaticAndDynamicReturnValues);
+        const returnValue = ['0x01020304', '0x05060708'];
+        const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        // Validate decoded return value
+        expect(decodedReturnValue).to.be.deep.equal(returnValue);
+    });
+});
diff --git a/packages/utils/test/utils/chai_setup.ts b/packages/utils/test/utils/chai_setup.ts
new file mode 100644
index 000000000..1a8733093
--- /dev/null
+++ b/packages/utils/test/utils/chai_setup.ts
@@ -0,0 +1,13 @@
+import * as chai from 'chai';
+import chaiAsPromised = require('chai-as-promised');
+import ChaiBigNumber = require('chai-bignumber');
+import * as dirtyChai from 'dirty-chai';
+
+export const chaiSetup = {
+    configure(): void {
+        chai.config.includeStack = true;
+        chai.use(ChaiBigNumber());
+        chai.use(dirtyChai);
+        chai.use(chaiAsPromised);
+    },
+};