Merge branch 'development' into feature/monorepo-scripts/publishToDockerHub

* development: (87 commits)
  Update packages/sol-tracing-utils/src/trace_collection_subprovider.ts
  Make mapping namings direct
  Remove unused tslint disable
  Revert "Remove logAsyncErrors hack"
  Remove logAsyncErrors hack
  Refactor logAsyncErrors to follow our conventions
  Export Sources and SourceCodes out of tracing utils
  Replace console.log with logUtils.log (#1515)
  strict decoding of return values using generics
  makerAssetFillAmount -> takerAssetFillAmount
  Ran prettier
  Linter
  Fix build after rebase
  Style cleanup for Compressed Calldata in Contract Wrappers PR
  Use simpler `_.find` to locate fillOrderBai
  Updated dutch auction wrapper
  Added back abi-gen-wrappers
  Renamed signatureParser.ts to signature_parser.ts
  Renamed decode rule `structsAsObjects` to `shouldConvertStructsToObjects`
  circle build failed. New commit to resubmit job.
  ...

25 files changed, 520 insertions, 112 deletions

diff --git a/packages/utils/CHANGELOG.json b/packages/utils/CHANGELOG.json
index 6b4bc3e82..34d681827 100644
--- a/packages/utils/CHANGELOG.json
+++ b/packages/utils/CHANGELOG.json
@@ -6,7 +6,8 @@
                 "note": "Make `promisify` resolve when the callback error is undefined.",
                 "pr": 1501
             }
-        ]
+        ],
+        "timestamp": 1547225310
     },
     {
         "version": "2.1.1",
diff --git a/packages/utils/CHANGELOG.md b/packages/utils/CHANGELOG.md
index 15d78e321..3873f33e0 100644
--- a/packages/utils/CHANGELOG.md
+++ b/packages/utils/CHANGELOG.md
@@ -5,6 +5,10 @@ Edit the package's CHANGELOG.json file only.
 
 CHANGELOG
 
+## v3.0.0 - _January 11, 2019_
+
+    * Make `promisify` resolve when the callback error is undefined. (#1501)
+
 ## v2.1.1 - _January 9, 2019_
 
     * Add `should` prefix to names of properties in EncodingRules and DecodingRules (#1363)
diff --git a/packages/utils/package.json b/packages/utils/package.json
index 49d6e3013..13ac9a377 100644
--- a/packages/utils/package.json
+++ b/packages/utils/package.json
@@ -1,6 +1,6 @@
 {
     "name": "@0x/utils",
-    "version": "2.1.1",
+    "version": "3.0.0",
     "engines": {
         "node": ">=6.12"
     },
@@ -28,7 +28,7 @@
     },
     "homepage": "https://github.com/0xProject/0x-monorepo/packages/utils/README.md",
     "devDependencies": {
-        "@0x/tslint-config": "^2.0.0",
+        "@0x/tslint-config": "^2.0.1",
         "@types/detect-node": "2.0.0",
         "@types/lodash": "4.14.104",
         "@types/mocha": "^2.2.42",
@@ -44,14 +44,14 @@
         "typescript": "3.0.1"
     },
     "dependencies": {
-        "@0x/types": "^1.5.0",
-        "@0x/typescript-typings": "^3.0.6",
+        "@0x/types": "^1.5.1",
+        "@0x/typescript-typings": "^3.0.7",
         "@types/node": "*",
         "abortcontroller-polyfill": "^1.1.9",
         "bignumber.js": "~4.1.0",
         "chalk": "^2.4.1",
         "detect-node": "2.0.3",
-        "ethereum-types": "^1.1.4",
+        "ethereum-types": "^1.1.5",
         "ethereumjs-util": "^5.1.1",
         "ethers": "~4.0.4",
         "isomorphic-fetch": "^2.2.1",
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
index 13cc87e2a..f23324721 100644
--- a/packages/utils/src/abi_encoder/abstract_data_types/data_type.ts
+++ b/packages/utils/src/abi_encoder/abstract_data_types/data_type.ts
@@ -51,8 +51,26 @@ export abstract class DataType {
         return value;
     }
 
+    public decodeAsArray(returndata: string, rules?: DecodingRules): any[] {
+        const value = this.decode(returndata, rules);
+        const valuesAsArray = _.isObject(value) ? _.values(value) : [value];
+        return valuesAsArray;
+    }
+
+    public getSignature(isDetailed?: boolean): string {
+        if (_.isEmpty(this._dataItem.name) || !isDetailed) {
+            return this.getSignatureType();
+        }
+        const name = this.getDataItem().name;
+        const lastIndexOfScopeDelimiter = name.lastIndexOf('.');
+        const isScopedName = !_.isUndefined(lastIndexOfScopeDelimiter) && lastIndexOfScopeDelimiter > 0;
+        const shortName = isScopedName ? name.substr((lastIndexOfScopeDelimiter as number) + 1) : name;
+        const detailedSignature = `${shortName} ${this.getSignatureType()}`;
+        return detailedSignature;
+    }
+
     public abstract generateCalldataBlock(value: any, parentBlock?: CalldataBlock): CalldataBlock;
     public abstract generateValue(calldata: RawCalldata, rules: DecodingRules): any;
-    public abstract getSignature(): string;
+    public abstract getSignatureType(): string;
     public abstract isStatic(): boolean;
 }
diff --git a/packages/utils/src/abi_encoder/abstract_data_types/types/set.ts b/packages/utils/src/abi_encoder/abstract_data_types/types/set.ts
index 00059a4b6..2c6c4b0f6 100644
--- a/packages/utils/src/abi_encoder/abstract_data_types/types/set.ts
+++ b/packages/utils/src/abi_encoder/abstract_data_types/types/set.ts
@@ -1,3 +1,4 @@
+import { ObjectMap } from '@0x/types';
 import { DataItem } from 'ethereum-types';
 import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
@@ -134,31 +135,26 @@ export abstract class AbstractSetDataType extends DataType {
         const block = new SetCalldataBlock(this.getDataItem().name, this.getSignature(), parentName);
         // Create blocks for members of set.
         const memberCalldataBlocks: CalldataBlock[] = [];
-        const childMap = _.cloneDeep(this._memberIndexByName);
-        _.forOwn(obj, (value: any, key: string) => {
-            if (!(key in childMap)) {
+        _.forEach(this._memberIndexByName, (memberIndex: number, memberName: string) => {
+            if (!(memberName in obj)) {
                 throw new Error(
-                    `Could not assign tuple to object: unrecognized key '${key}' in object ${this.getDataItem().name}`,
+                    `Could not assign tuple to object: missing key '${memberName}' in object ${JSON.stringify(obj)}`,
                 );
             }
-            const memberBlock = this._members[this._memberIndexByName[key]].generateCalldataBlock(value, block);
+            const memberValue: any = (obj as ObjectMap<any>)[memberName];
+            const memberBlock = this._members[memberIndex].generateCalldataBlock(memberValue, 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 {
+    protected _computeSignatureOfMembers(isDetailed?: boolean): string {
         // Compute signature of members
         let signature = `(`;
         _.each(this._members, (member: DataType, i: number) => {
-            signature += member.getSignature();
+            signature += member.getSignature(isDetailed);
             if (i < this._members.length - 1) {
                 signature += ',';
             }
@@ -179,17 +175,27 @@ export abstract class AbstractSetDataType extends DataType {
         // Create one member for each component of `dataItem`
         const members: DataType[] = [];
         const memberIndexByName: MemberIndexByName = {};
+        const memberNames: string[] = [];
         _.each(dataItem.components, (memberItem: DataItem) => {
+            // If a component with `name` already exists then
+            // rename to `name_nameIdx` to avoid naming conflicts.
+            let memberName = memberItem.name;
+            let nameIdx = 0;
+            while (_.includes(memberNames, memberName) || _.isEmpty(memberName)) {
+                nameIdx++;
+                memberName = `${memberItem.name}_${nameIdx}`;
+            }
+            memberNames.push(memberName);
             const childDataItem: DataItem = {
                 type: memberItem.type,
-                name: `${dataItem.name}.${memberItem.name}`,
+                name: `${dataItem.name}.${memberName}`,
             };
             const components = memberItem.components;
             if (!_.isUndefined(components)) {
                 childDataItem.components = components;
             }
             const child = this.getFactory().create(childDataItem, this);
-            memberIndexByName[memberItem.name] = members.length;
+            memberIndexByName[memberName] = members.length;
             members.push(child);
         });
         return [members, memberIndexByName];
diff --git a/packages/utils/src/abi_encoder/evm_data_type_factory.ts b/packages/utils/src/abi_encoder/evm_data_type_factory.ts
index 4cc124e0a..268649148 100644
--- a/packages/utils/src/abi_encoder/evm_data_type_factory.ts
+++ b/packages/utils/src/abi_encoder/evm_data_type_factory.ts
@@ -2,6 +2,8 @@
 import { DataItem, MethodAbi } from 'ethereum-types';
 import * as _ from 'lodash';
 
+import { generateDataItemsFromSignature } from './utils/signature_parser';
+
 import { DataType } from './abstract_data_types/data_type';
 import { DataTypeFactory } from './abstract_data_types/interfaces';
 import { AddressDataType } from './evm_data_types/address';
@@ -129,4 +131,35 @@ export class EvmDataTypeFactory implements DataTypeFactory {
 
     private constructor() {}
 }
+
+/**
+ * Convenience function for creating a DataType from different inputs.
+ * @param input A single or set of DataItem or a DataType signature.
+ *              A signature in the form of '<type>' is interpreted as a `DataItem`
+ *              For example, 'string' is interpreted as {type: 'string'}
+ *              A signature in the form '(<type1>, <type2>, ..., <typen>)' is interpreted as `DataItem[]`
+ *              For eaxmple, '(string, uint256)' is interpreted as [{type: 'string'}, {type: 'uint256'}]
+ * @return DataType corresponding to input.
+ */
+export function create(input: DataItem | DataItem[] | string): DataType {
+    // Handle different types of input
+    const isSignature = typeof input === 'string';
+    const isTupleSignature = isSignature && (input as string).startsWith('(');
+    const shouldParseAsTuple = isTupleSignature || _.isArray(input);
+    // Create input `dataItem`
+    let dataItem: DataItem;
+    if (shouldParseAsTuple) {
+        const dataItems = isSignature ? generateDataItemsFromSignature(input as string) : (input as DataItem[]);
+        dataItem = {
+            name: '',
+            type: 'tuple',
+            components: dataItems,
+        };
+    } else {
+        dataItem = isSignature ? generateDataItemsFromSignature(input as string)[0] : (input as DataItem);
+    }
+    // Create data type
+    const dataType = EvmDataTypeFactory.getInstance().create(dataItem);
+    return dataType;
+}
 /* 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
index 2e3a206c6..2278830eb 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/address.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/address.ts
@@ -39,10 +39,11 @@ export class AddressDataType extends AbstractBlobDataType {
         const valueBufPadded = calldata.popWord();
         const valueBuf = valueBufPadded.slice(AddressDataType._DECODED_ADDRESS_OFFSET_IN_BYTES);
         const value = ethUtil.bufferToHex(valueBuf);
-        return value;
+        const valueLowercase = _.toLower(value);
+        return valueLowercase;
     }
 
-    public getSignature(): string {
+    public getSignatureType(): 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
index 7595cb667..d9607f47e 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/array.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/array.ts
@@ -7,7 +7,6 @@ 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 {
@@ -35,25 +34,36 @@ export class ArrayDataType extends AbstractSetDataType {
         super(dataItem, dataTypeFactory, isArray, arrayLength, arrayElementType);
         // Set array properties
         this._elementType = arrayElementType;
-        this._arraySignature = this._computeSignature();
     }
 
-    public getSignature(): string {
-        return this._arraySignature;
+    public getSignatureType(): string {
+        return this._computeSignature(false);
     }
 
-    private _computeSignature(): string {
+    public getSignature(isDetailed?: boolean): string {
+        if (_.isEmpty(this.getDataItem().name) || !isDetailed) {
+            return this.getSignatureType();
+        }
+        const name = this.getDataItem().name;
+        const lastIndexOfScopeDelimiter = name.lastIndexOf('.');
+        const isScopedName = !_.isUndefined(lastIndexOfScopeDelimiter) && lastIndexOfScopeDelimiter > 0;
+        const shortName = isScopedName ? name.substr((lastIndexOfScopeDelimiter as number) + 1) : name;
+        const detailedSignature = `${shortName} ${this._computeSignature(isDetailed)}`;
+        return detailedSignature;
+    }
+
+    private _computeSignature(isDetailed?: boolean): string {
         // Compute signature for a single array element
         const elementDataItem: DataItem = {
             type: this._elementType,
-            name: 'N/A',
+            name: '',
         };
         const elementComponents = this.getDataItem().components;
         if (!_.isUndefined(elementComponents)) {
             elementDataItem.components = elementComponents;
         }
         const elementDataType = this.getFactory().create(elementDataItem);
-        const elementSignature = elementDataType.getSignature();
+        const elementSignature = elementDataType.getSignature(isDetailed);
         // Construct signature for array of type `element`
         if (_.isUndefined(this._arrayLength)) {
             return `${elementSignature}[]`;
diff --git a/packages/utils/src/abi_encoder/evm_data_types/bool.ts b/packages/utils/src/abi_encoder/evm_data_types/bool.ts
index d713d5a94..7f91f34e6 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/bool.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/bool.ts
@@ -46,7 +46,7 @@ export class BoolDataType extends AbstractBlobDataType {
         return value;
     }
 
-    public getSignature(): string {
+    public getSignatureType(): 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
index 5277efd6c..fa38b63c0 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/dynamic_bytes.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/dynamic_bytes.ts
@@ -65,7 +65,7 @@ export class DynamicBytesDataType extends AbstractBlobDataType {
         return value;
     }
 
-    public getSignature(): string {
+    public getSignatureType(): 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
index f1dcf5ea1..8d98e195b 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/int.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/int.ts
@@ -47,13 +47,17 @@ export class IntDataType extends AbstractBlobDataType {
         return encodedValue;
     }
 
-    public decodeValue(calldata: RawCalldata): BigNumber {
+    public decodeValue(calldata: RawCalldata): BigNumber | number {
         const valueBuf = calldata.popWord();
         const value = EncoderMath.safeDecodeNumericValue(valueBuf, this._minValue, this._maxValue);
+        const numberOfBytesInUint8 = 8;
+        if (this._width === numberOfBytesInUint8) {
+            return value.toNumber();
+        }
         return value;
     }
 
-    public getSignature(): string {
+    public getSignatureType(): 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
index b1cd1377f..c852a0fdf 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/method.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/method.ts
@@ -44,7 +44,20 @@ export class MethodDataType extends AbstractSetDataType {
         return returnValues;
     }
 
-    public getSignature(): string {
+    public strictDecodeReturnValue<T>(returndata: string, rules?: DecodingRules): T {
+        const returnValues = this._returnDataType.decode(returndata, rules);
+        const returnValuesAsArray: any = _.isObject(returnValues) ? _.values(returnValues) : [returnValues];
+        switch (returnValuesAsArray.length) {
+            case 0:
+                return undefined as any;
+            case 1:
+                return returnValuesAsArray[0];
+            default:
+                return returnValuesAsArray;
+        }
+    }
+
+    public getSignatureType(): string {
         return this._methodSignature;
     }
 
diff --git a/packages/utils/src/abi_encoder/evm_data_types/pointer.ts b/packages/utils/src/abi_encoder/evm_data_types/pointer.ts
index 389e75927..250db7c64 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/pointer.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/pointer.ts
@@ -11,7 +11,11 @@ export class PointerDataType extends AbstractPointerDataType {
         super(dataItem, dataTypeFactory, destDataType, parentDataType);
     }
 
-    public getSignature(): string {
-        return this._destination.getSignature();
+    public getSignatureType(): string {
+        return this._destination.getSignature(false);
+    }
+
+    public getSignature(isDetailed?: boolean): string {
+        return this._destination.getSignature(isDetailed);
     }
 }
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
index 2e371c505..cbf1957d7 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
@@ -36,7 +36,7 @@ export class StaticBytesDataType extends AbstractBlobDataType {
         this._width = StaticBytesDataType._decodeWidthFromType(dataItem.type);
     }
 
-    public getSignature(): string {
+    public getSignatureType(): string {
         // Note that `byte` reduces to `bytes1`
         return `${SolidityTypes.Bytes}${this._width}`;
     }
diff --git a/packages/utils/src/abi_encoder/evm_data_types/string.ts b/packages/utils/src/abi_encoder/evm_data_types/string.ts
index 91a72ad3f..97ac46442 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/string.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/string.ts
@@ -52,7 +52,7 @@ export class StringDataType extends AbstractBlobDataType {
         return value;
     }
 
-    public getSignature(): string {
+    public getSignatureType(): 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
index 31593c882..5000c85e8 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/tuple.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/tuple.ts
@@ -1,11 +1,10 @@
 import { DataItem, SolidityTypes } from 'ethereum-types';
+import * as _ from 'lodash';
 
 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;
     }
@@ -15,10 +14,21 @@ export class TupleDataType extends AbstractSetDataType {
         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;
+    public getSignatureType(): string {
+        return this._computeSignatureOfMembers(false);
+    }
+
+    public getSignature(isDetailed?: boolean): string {
+        if (_.isEmpty(this.getDataItem().name) || !isDetailed) {
+            return this.getSignatureType();
+        }
+        const name = this.getDataItem().name;
+        const lastIndexOfScopeDelimiter = name.lastIndexOf('.');
+        const isScopedName = !_.isUndefined(lastIndexOfScopeDelimiter) && lastIndexOfScopeDelimiter > 0;
+        const shortName = isScopedName ? name.substr((lastIndexOfScopeDelimiter as number) + 1) : name;
+        const detailedSignature = `${shortName} ${this._computeSignatureOfMembers(isDetailed)}`;
+        return detailedSignature;
     }
 }
diff --git a/packages/utils/src/abi_encoder/evm_data_types/uint.ts b/packages/utils/src/abi_encoder/evm_data_types/uint.ts
index 5180f0cf3..8e382e8dc 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/uint.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/uint.ts
@@ -46,13 +46,17 @@ export class UIntDataType extends AbstractBlobDataType {
         return encodedValue;
     }
 
-    public decodeValue(calldata: RawCalldata): BigNumber {
+    public decodeValue(calldata: RawCalldata): BigNumber | number {
         const valueBuf = calldata.popWord();
         const value = EncoderMath.safeDecodeNumericValue(valueBuf, UIntDataType._MIN_VALUE, this._maxValue);
+        const numberOfBytesInUint8 = 8;
+        if (this._width === numberOfBytesInUint8) {
+            return value.toNumber();
+        }
         return value;
     }
 
-    public getSignature(): string {
+    public getSignatureType(): string {
         return `${SolidityTypes.Uint}${this._width}`;
     }
 }
diff --git a/packages/utils/src/abi_encoder/index.ts b/packages/utils/src/abi_encoder/index.ts
index baf844ac6..cfacfe075 100644
--- a/packages/utils/src/abi_encoder/index.ts
+++ b/packages/utils/src/abi_encoder/index.ts
@@ -11,4 +11,6 @@ export {
     String,
     Tuple,
     UInt,
+    create,
 } from './evm_data_type_factory';
+export { DataType } from './abstract_data_types/data_type';
diff --git a/packages/utils/src/abi_encoder/utils/constants.ts b/packages/utils/src/abi_encoder/utils/constants.ts
index 36de2dd4f..fc586f295 100644
--- a/packages/utils/src/abi_encoder/utils/constants.ts
+++ b/packages/utils/src/abi_encoder/utils/constants.ts
@@ -11,7 +11,7 @@ export const constants = {
     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: { shouldConvertStructsToObjects: false } as DecodingRules,
+    DEFAULT_DECODING_RULES: { shouldConvertStructsToObjects: true } as DecodingRules,
     DEFAULT_ENCODING_RULES: { shouldOptimize: true, shouldAnnotate: false } as EncodingRules,
     /* tslint:enable no-object-literal-type-assertion */
 };
diff --git a/packages/utils/src/abi_encoder/utils/signature_parser.ts b/packages/utils/src/abi_encoder/utils/signature_parser.ts
new file mode 100644
index 000000000..315784cea
--- /dev/null
+++ b/packages/utils/src/abi_encoder/utils/signature_parser.ts
@@ -0,0 +1,101 @@
+import { DataItem } from 'ethereum-types';
+import * as _ from 'lodash';
+
+/**
+ * Returns an array of DataItem's corresponding to the input signature.
+ * A signature can be in two forms: '<DataItem.type>' or '(<DataItem1.type>, <DataItem2.type>, ...)
+ * An example of the first form would be 'address' or 'uint256'
+ * An example of the second form would be '(address, uint256)'
+ * Signatures can also include a name field, for example: 'foo address' or '(foo address, bar uint256)'
+ * @param signature of input DataItems
+ * @return DataItems derived from input signature
+ */
+export function generateDataItemsFromSignature(signature: string): DataItem[] {
+    let trimmedSignature = signature;
+    if (signature.startsWith('(')) {
+        if (!signature.endsWith(')')) {
+            throw new Error(`Failed to generate data item. Must end with ')'`);
+        }
+        trimmedSignature = signature.substr(1, signature.length - 2);
+    }
+    trimmedSignature += ',';
+    let isCurrTokenArray = false;
+    let currTokenArrayModifier = '';
+    let isParsingArrayModifier = false;
+    let currToken = '';
+    let parenCount = 0;
+    let currTokenName = '';
+    const dataItems: DataItem[] = [];
+    for (const char of trimmedSignature) {
+        // Tokenize the type string while keeping track of parentheses.
+        switch (char) {
+            case '(':
+                parenCount += 1;
+                currToken += char;
+                break;
+            case ')':
+                parenCount -= 1;
+                currToken += char;
+                break;
+            case '[':
+                if (parenCount === 0) {
+                    isParsingArrayModifier = true;
+                    isCurrTokenArray = true;
+                    currTokenArrayModifier += '[';
+                } else {
+                    currToken += char;
+                }
+                break;
+            case ']':
+                if (parenCount === 0) {
+                    isParsingArrayModifier = false;
+                    currTokenArrayModifier += ']';
+                } else {
+                    currToken += char;
+                }
+                break;
+            case ' ':
+                if (parenCount === 0) {
+                    currTokenName = currToken;
+                    currToken = '';
+                } else {
+                    currToken += char;
+                }
+                break;
+            case ',':
+                if (parenCount === 0) {
+                    // Generate new DataItem from token
+                    const components = currToken.startsWith('(') ? generateDataItemsFromSignature(currToken) : [];
+                    const isTuple = !_.isEmpty(components);
+                    const dataItem: DataItem = { name: currTokenName, type: '' };
+                    if (isTuple) {
+                        dataItem.type = 'tuple';
+                        dataItem.components = components;
+                    } else {
+                        dataItem.type = currToken;
+                    }
+                    if (isCurrTokenArray) {
+                        dataItem.type += currTokenArrayModifier;
+                    }
+                    dataItems.push(dataItem);
+                    // reset token state
+                    currTokenName = '';
+                    currToken = '';
+                    isCurrTokenArray = false;
+                    currTokenArrayModifier = '';
+                    break;
+                } else {
+                    currToken += char;
+                    break;
+                }
+            default:
+                if (isParsingArrayModifier) {
+                    currTokenArrayModifier += char;
+                } else {
+                    currToken += char;
+                }
+                break;
+        }
+    }
+    return dataItems;
+}
diff --git a/packages/utils/test/abi_encoder/evm_data_types_test.ts b/packages/utils/test/abi_encoder/evm_data_types_test.ts
index 55d582d10..54d536a7e 100644
--- a/packages/utils/test/abi_encoder/evm_data_types_test.ts
+++ b/packages/utils/test/abi_encoder/evm_data_types_test.ts
@@ -26,6 +26,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Dynamic size; Static elements', async () => {
             // Create DataType object
@@ -41,6 +45,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Fixed size; Dynamic elements', async () => {
             // Create DataType object
@@ -56,6 +64,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Dynamic size; Dynamic elements', async () => {
             // Create DataType object
@@ -71,6 +83,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Dynamic Size; Multidimensional; Dynamic Elements', async () => {
             // Create DataType object
@@ -89,6 +105,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Dynamic Size; Multidimensional; Static Elements', async () => {
             // Create DataType object
@@ -107,6 +127,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Static Size; Multidimensional; Static Elements', async () => {
             // Create DataType object
@@ -124,6 +148,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Static Size; Multidimensional; Dynamic Elements', async () => {
             // Create DataType object
@@ -141,6 +169,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Static size; Too Few Elements', async () => {
             // Create DataType object
@@ -197,6 +229,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodingRules: AbiEncoder.DecodingRules = { shouldConvertStructsToObjects: true };
             const decodedArgs = dataType.decode(encodedArgs, decodingRules);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args, encodingRules);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Dynamic elements only', async () => {
             // Create DataType object
@@ -217,6 +253,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodingRules: AbiEncoder.DecodingRules = { shouldConvertStructsToObjects: true };
             const decodedArgs = dataType.decode(encodedArgs, decodingRules);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Nested Static Array', async () => {
             // Create DataType object
@@ -237,6 +277,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodingRules: AbiEncoder.DecodingRules = { shouldConvertStructsToObjects: true };
             const decodedArgs = dataType.decode(encodedArgs, decodingRules);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Nested Dynamic Array', async () => {
             // Create DataType object
@@ -257,6 +301,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodingRules: AbiEncoder.DecodingRules = { shouldConvertStructsToObjects: true };
             const decodedArgs = dataType.decode(encodedArgs, decodingRules);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Nested Static Multidimensional Array', async () => {
             // Create DataType object
@@ -279,6 +327,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodingRules: AbiEncoder.DecodingRules = { shouldConvertStructsToObjects: true };
             const decodedArgs = dataType.decode(encodedArgs, decodingRules);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Nested Dynamic Multidimensional Array', async () => {
             // Create DataType object
@@ -301,6 +353,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodingRules: AbiEncoder.DecodingRules = { shouldConvertStructsToObjects: true };
             const decodedArgs = dataType.decode(encodedArgs, decodingRules);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Static and dynamic elements mixed', async () => {
             // Create DataType object
@@ -331,6 +387,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodingRules: AbiEncoder.DecodingRules = { shouldConvertStructsToObjects: true };
             const decodedArgs = dataType.decode(encodedArgs, decodingRules);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Missing Key', async () => {
             // Create DataType object
@@ -345,22 +405,7 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // 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");
+            }).to.throw('Could not assign tuple to object: missing key \'field_2\' in object {"field_1":"-5"}');
         });
     });
 
@@ -378,6 +423,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Invalid Address - input is not valid hex', async () => {
             // Create DataType object
@@ -417,6 +466,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('False', async () => {
             // Create DataType object
@@ -431,6 +484,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
     });
 
@@ -455,6 +512,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int256 - Negative Base Case', async () => {
             // Create DataType object
@@ -469,6 +530,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int256 - Positive Value', async () => {
             // Create DataType object
@@ -483,6 +548,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int256 - Negative Value', async () => {
             // Create DataType object
@@ -497,6 +566,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int256 - Value too large', async () => {
             // Create DataType object
@@ -533,6 +606,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int32 - Negative Base Case', async () => {
             // Create DataType object
@@ -547,6 +624,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int32 - Positive Value', async () => {
             // Create DataType object
@@ -561,6 +642,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int32 - Negative Value', async () => {
             // Create DataType object
@@ -575,6 +660,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Int32 - Value too large', async () => {
             // Create DataType object
@@ -621,6 +710,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('UInt256 - Positive Value', async () => {
             // Create DataType object
@@ -635,6 +728,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('UInt256 - Zero Value', async () => {
             // Create DataType object
@@ -649,6 +746,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('UInt256 - Value too large', async () => {
             // Create DataType object
@@ -685,6 +786,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('UInt32 - Positive Value', async () => {
             // Create DataType object
@@ -699,6 +804,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('UInt32 - Zero Value', async () => {
             // Create DataType object
@@ -713,6 +822,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('UInt32 - Value too large', async () => {
             // Create DataType object
@@ -752,6 +865,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Single Byte (bytes1)', async () => {
             // Create DataType object
@@ -766,6 +883,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('4 Bytes (bytes4)', async () => {
             // Create DataType object
@@ -780,6 +901,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('4 Bytes (bytes4); Encoder must pad input', async () => {
             // Create DataType object
@@ -796,6 +921,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodedArgs = dataType.decode(encodedArgs);
             const paddedArgs = '0x1a180000';
             expect(decodedArgs).to.be.deep.equal(paddedArgs);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('32 Bytes (bytes32)', async () => {
             // Create DataType object
@@ -810,6 +939,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('32 Bytes (bytes32); Encoder must pad input', async () => {
             // Create DataType object
@@ -826,6 +959,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             const decodedArgs = dataType.decode(encodedArgs);
             const paddedArgs = '0x1a18bf6100000000000000000000000000000000000000000000000000000000';
             expect(decodedArgs).to.be.deep.equal(paddedArgs);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Should throw when pass in too many bytes (bytes4)', async () => {
             // Create DataType object
@@ -893,6 +1030,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Spans multiple EVM words', async () => {
             // Create DataType object
@@ -910,6 +1051,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Input as Buffer', async () => {
             // Create DataType object
@@ -927,6 +1072,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Should throw when pass in bad hex (no 0x prefix)', async () => {
             // Create DataType object
@@ -968,6 +1117,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('Spans multiple EVM words', async () => {
             // Create DataType object
@@ -985,6 +1138,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
         it('String that begins with 0x prefix', async () => {
             // Create DataType object
@@ -1002,6 +1159,10 @@ describe('ABI Encoder: EVM Data Type Encoding/Decoding', () => {
             // Decode Encoded Args and validate result
             const decodedArgs = dataType.decode(encodedArgs);
             expect(decodedArgs).to.be.deep.equal(args);
+            // Validate signature
+            const dataTypeFromSignature = AbiEncoder.create(dataType.getSignature(true));
+            const argsEncodedFromSignature = dataTypeFromSignature.encode(args);
+            expect(argsEncodedFromSignature).to.be.deep.equal(expectedEncodedArgs);
         });
     });
 });
diff --git a/packages/utils/test/abi_encoder/methods_test.ts b/packages/utils/test/abi_encoder/methods_test.ts
index a0525967e..d8045fece 100644
--- a/packages/utils/test/abi_encoder/methods_test.ts
+++ b/packages/utils/test/abi_encoder/methods_test.ts
@@ -21,7 +21,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x09f2b0c30000000000000000000000000000000000000000000000000000000000000001ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff560000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00000000000000000000000000000000000000000000000000000000000000015600000000000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Array of Static Tuples (Array has defined length)', async () => {
@@ -40,7 +41,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x9eb20969000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000700000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000010';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Array of Static Tuples (Array has dynamic length)', async () => {
@@ -59,7 +61,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x63275d6e00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000700000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000010';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Array of Dynamic Tuples (Array has defined length)', async () => {
@@ -78,7 +81,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0xdeedb00f00000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000018000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000280000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000003800000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000048000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000013400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000500000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000001360000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000138000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023130000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023134000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023136000000000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Array of Dynamic Tuples (Array has dynamic length)', async () => {
@@ -97,7 +101,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x60c847fb000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000018000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000280000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000003800000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000048000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000013400000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000500000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000001360000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000138000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023130000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023132000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023134000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000f000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000023136000000000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Multidimensional Arrays / Static Members', async () => {
@@ -108,19 +113,16 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
         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)]],
-            ]);
+            args.push([[[++value, ++value], [++value, ++value]], [[++value, ++value], [++value, ++value]]]);
         }
         const calldata = method.encode(args, encodingRules);
         // Validate calldata
         const expectedCalldata =
             '0xc2f47d6f00000000000000000000000000000000000000000000000000000000000001e00000000000000000000000000000000000000000000000000000000000000480000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000009600000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000d400000000000000000000000000000000000000000000000000000000000000e600000000000000000000000000000000000000000000000000000000000000039000000000000000000000000000000000000000000000000000000000000003a000000000000000000000000000000000000000000000000000000000000003b000000000000000000000000000000000000000000000000000000000000003c000000000000000000000000000000000000000000000000000000000000003d000000000000000000000000000000000000000000000000000000000000003e000000000000000000000000000000000000000000000000000000000000003f00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000001600000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000300000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000050000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000070000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000001600000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000009000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000c0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000110000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000130000000000000000000000000000000000000000000000000000000000000014000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a00000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000001500000000000000000000000000000000000000000000000000000000000000160000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000001700000000000000000000000000000000000000000000000000000000000000180000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000019000000000000000000000000000000000000000000000000000000000000001a000000000000000000000000000000000000000000000000000000000000001b000000000000000000000000000000000000000000000000000000000000001c0000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000001d000000000000000000000000000000000000000000000000000000000000001e000000000000000000000000000000000000000000000000000000000000001f000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000140000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000210000000000000000000000000000000000000000000000000000000000000022000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000230000000000000000000000000000000000000000000000000000000000000024000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000025000000000000000000000000000000000000000000000000000000000000002600000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000027000000000000000000000000000000000000000000000000000000000000002800000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000029000000000000000000000000000000000000000000000000000000000000002a000000000000000000000000000000000000000000000000000000000000002b000000000000000000000000000000000000000000000000000000000000002c000000000000000000000000000000000000000000000000000000000000002d000000000000000000000000000000000000000000000000000000000000002e000000000000000000000000000000000000000000000000000000000000002f0000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000003100000000000000000000000000000000000000000000000000000000000000320000000000000000000000000000000000000000000000000000000000000033000000000000000000000000000000000000000000000000000000000000003400000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000035000000000000000000000000000000000000000000000000000000000000003600000000000000000000000000000000000000000000000000000000000000370000000000000000000000000000000000000000000000000000000000000038';
         expect(calldata).to.be.equal(expectedCalldata);
-        expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Multidimensional Arrays / Dynamic Members', async () => {
@@ -148,7 +150,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x81534ebd0000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000052000000000000000000000000000000000000000000000000000000000000009a00000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000260000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000131000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001320000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000013300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000134000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000001200000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000001350000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000013600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000137000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001380000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000260000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000139000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002313000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000023131000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000231320000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000001200000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000002313300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000023134000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000231350000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002313600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000024000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000231370000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002313800000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000023139000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000232300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000012000000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000023231000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000232320000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000002323300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000023234000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000232350000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002323600000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000232370000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002323800000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000002323900000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000023330000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000002333100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000023332000000000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Fixed Length Array / Dynamic Members', async () => {
@@ -161,7 +164,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x243a6e6e0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Fixed Length Array / Dynamic Members', async () => {
@@ -174,7 +178,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x243a6e6e0000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Unfixed Length Array / Dynamic Members ABI', async () => {
@@ -187,33 +192,40 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x13e751a900000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000005427261766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000034e657700000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         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)]];
+        // tslint:disable custom-no-magic-numbers
+        const args = [[127, 14, 54]];
+        // tslint:enable custom-no-magic-numbers
         const calldata = method.encode(args, encodingRules);
         // Validate calldata
         const expectedCalldata =
             '0x4fc8a83300000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000007f000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000036';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         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)]];
+        // tslint:disable custom-no-magic-numbers
+        const args = [[127, 14, 54]];
+        // tslint:enable custom-no-magic-numbers
         const calldata = method.encode(args, encodingRules);
         // Validate calldata
         const expectedCalldata =
             '0xf68ade72000000000000000000000000000000000000000000000000000000000000007f000000000000000000000000000000000000000000000000000000000000000e0000000000000000000000000000000000000000000000000000000000000036';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Array ABI', async () => {
@@ -226,7 +238,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x13e751a900000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000046669766500000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000373697800000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005736576656e000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Static Tuple', async () => {
@@ -240,7 +253,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0xa9125e150000000000000000000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000f0000000000000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Dynamic Tuple (Array input)', async () => {
@@ -254,7 +268,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x5b998f3500000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000046669766500000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Dynamic Tuple (Object input)', async () => {
@@ -268,7 +283,8 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '0x5b998f3500000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000046669766500000000000000000000000000000000000000000000000000000000';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         expect(decodedValue).to.be.deep.equal(args);
     });
     it('Large, Flat ABI', async () => {
@@ -291,13 +307,16 @@ describe('ABI Encoder: Method Encoding / Decoding', () => {
             '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';
         expect(calldata).to.be.equal(expectedCalldata);
         // Validate decoding
-        const decodedValue = method.decode(calldata);
+        const decodingRules = { shouldConvertStructsToObjects: false };
+        const decodedValue = method.decode(calldata, decodingRules);
         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)];
+        // tslint:disable custom-no-magic-numbers
+        const someStaticArray = [127, 14, 54];
+        // tslint:enable custom-no-magic-numbers
         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.',
diff --git a/packages/utils/test/abi_encoder/optimizer_test.ts b/packages/utils/test/abi_encoder/optimizer_test.ts
index ee0654ec3..c2881f14c 100644
--- a/packages/utils/test/abi_encoder/optimizer_test.ts
+++ b/packages/utils/test/abi_encoder/optimizer_test.ts
@@ -23,7 +23,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x7221063300000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000640000000000000000000000000000000000000000000000000000000000000096';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Dynamic Arrays with Dynamic Elements', async () => {
@@ -38,7 +38,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0xbb4f12e300000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Static Arrays with Static Elements (should not optimize)', async () => {
@@ -55,7 +55,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
         const unoptimizedCalldata = method.encode(args);
         expect(optimizedCalldata).to.be.equal(unoptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Static Arrays with Dynamic Elements', async () => {
@@ -70,7 +70,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x9fe31f8e0000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Array Elements (should optimize)', async () => {
@@ -84,7 +84,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x13e751a900000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000c0000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000c0000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Tuple Fields', async () => {
@@ -98,7 +98,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x16780a5e000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000548656c6c6f000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Strings', async () => {
@@ -115,7 +115,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x07370bfa00000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000548656c6c6f000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Bytes', async () => {
@@ -133,7 +133,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x6045e42900000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000002801020304050607080910111213141516171819202122232425262728293031323334353637383940000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Tuples', async () => {
@@ -148,7 +148,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x564f826d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000006792a000000000000000000000000000000000000000000000000000000000000000d48656c6c6f2c20576f726c642100000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Fields Across Two Tuples', async () => {
@@ -164,7 +164,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x564f826d000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000d48656c6c6f2c20576f726c642100000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Arrays, Nested in Separate Tuples', async () => {
@@ -180,7 +180,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x18970a9e000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000600000000000000000000000000000000000000000000000000000000000000060000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000030000000000000000000000000000000000000000000000000000000000000064000000000000000000000000000000000000000000000000000000000000009600000000000000000000000000000000000000000000000000000000000000c80000000000000000000000000000000000000000000000000000000000000035657874726120617267756d656e7420746f2070726576656e742065786163746c79206d61746368696e6720746865207475706c65730000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Tuples, Nested in Separate Tuples', async () => {
@@ -196,7 +196,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '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';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Two-Dimensional Arrays', async () => {
@@ -211,7 +211,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x0d28c4f9000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000002c0000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c640000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000003466f6f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003426172000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000035a61610000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c640000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000e00000000000000000000000000000000000000000000000000000000000000003466f6f00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000003426172000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000035a61610000000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Duplicate Array, Nested within Separate Two-Dimensional Arrays', async () => {
@@ -226,14 +226,21 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x0d28c4f900000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000001200000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000003466f6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000080000000000000000000000000000000000000000000000000000000000000000548656c6c6f0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000005576f726c640000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000034261720000000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         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]]];
+        // tslint:disable custom-no-magic-numbers
+        const array = [100, 150, 200, 225];
+        // tslint:enable custom-no-magic-numbers
+        const tuple = [
+            [new BigNumber(array[0])],
+            [new BigNumber(array[1])],
+            [new BigNumber(array[2])],
+            [new BigNumber(array[3])],
+        ];
         const args = [array, tuple];
         // Validata calldata
         const optimizedCalldata = method.encode(args, encodingRules);
@@ -241,7 +248,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0x5b5c78fd0000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040000000000000000000000000000000000000000000000000000000000000064000000000000000000000000000000000000000000000000000000000000009600000000000000000000000000000000000000000000000000000000000000c800000000000000000000000000000000000000000000000000000000000000e1';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         expect(decodedArgs).to.be.deep.equal(args);
     });
     it('Array Elements Duplicated as Separate Parameter', async () => {
@@ -256,7 +263,7 @@ describe('ABI Encoder: Optimized Method Encoding/Decoding', () => {
             '0xe0e0d34900000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000120000000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000800000000000000000000000000000000000000000000000000000000000000005576f726c64000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000548656c6c6f000000000000000000000000000000000000000000000000000000';
         expect(optimizedCalldata).to.be.equal(expectedOptimizedCalldata);
         // Validate decoding
-        const decodedArgs = method.decode(optimizedCalldata);
+        const decodedArgs = method.decode(optimizedCalldata, { shouldConvertStructsToObjects: false });
         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
index 104c7f5db..308d11ee5 100644
--- a/packages/utils/test/abi_encoder/return_values_test.ts
+++ b/packages/utils/test/abi_encoder/return_values_test.ts
@@ -15,7 +15,7 @@ describe('ABI Encoder: Return Value Encoding/Decoding', () => {
         // Decode return value
         const method = new AbiEncoder.Method(ReturnValueAbis.noReturnValues);
         const returnValue = '0x';
-        const decodedReturnValue = method.decodeReturnValues(returnValue);
+        const decodedReturnValue = method.decodeReturnValues(returnValue, { shouldConvertStructsToObjects: false });
         const expectedDecodedReturnValue: any[] = [];
         expect(decodedReturnValue).to.be.deep.equal(expectedDecodedReturnValue);
     });
@@ -24,7 +24,9 @@ describe('ABI Encoder: Return Value Encoding/Decoding', () => {
         const method = new AbiEncoder.Method(ReturnValueAbis.singleStaticReturnValue);
         const returnValue = ['0x01020304'];
         const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
-        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue, {
+            shouldConvertStructsToObjects: false,
+        });
         // Validate decoded return value
         expect(decodedReturnValue).to.be.deep.equal(returnValue);
     });
@@ -33,7 +35,9 @@ describe('ABI Encoder: Return Value Encoding/Decoding', () => {
         const method = new AbiEncoder.Method(ReturnValueAbis.multipleStaticReturnValues);
         const returnValue = ['0x01020304', '0x05060708'];
         const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
-        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue, {
+            shouldConvertStructsToObjects: false,
+        });
         // Validate decoded return value
         expect(decodedReturnValue).to.be.deep.equal(returnValue);
     });
@@ -42,7 +46,9 @@ describe('ABI Encoder: Return Value Encoding/Decoding', () => {
         const method = new AbiEncoder.Method(ReturnValueAbis.singleDynamicReturnValue);
         const returnValue = ['0x01020304'];
         const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
-        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue, {
+            shouldConvertStructsToObjects: false,
+        });
         // Validate decoded return value
         expect(decodedReturnValue).to.be.deep.equal(returnValue);
     });
@@ -51,7 +57,9 @@ describe('ABI Encoder: Return Value Encoding/Decoding', () => {
         const method = new AbiEncoder.Method(ReturnValueAbis.multipleDynamicReturnValues);
         const returnValue = ['0x01020304', '0x05060708'];
         const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
-        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue, {
+            shouldConvertStructsToObjects: false,
+        });
         // Validate decoded return value
         expect(decodedReturnValue).to.be.deep.equal(returnValue);
     });
@@ -60,7 +68,9 @@ describe('ABI Encoder: Return Value Encoding/Decoding', () => {
         const method = new AbiEncoder.Method(ReturnValueAbis.mixedStaticAndDynamicReturnValues);
         const returnValue = ['0x01020304', '0x05060708'];
         const encodedReturnValue = method.encodeReturnValues(returnValue, encodingRules);
-        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue);
+        const decodedReturnValue = method.decodeReturnValues(encodedReturnValue, {
+            shouldConvertStructsToObjects: false,
+        });
         // Validate decoded return value
         expect(decodedReturnValue).to.be.deep.equal(returnValue);
     });
diff --git a/packages/utils/test/abi_encoder/signature_tests.ts b/packages/utils/test/abi_encoder/signature_tests.ts
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/packages/utils/test/abi_encoder/signature_tests.ts