Changed constants to an exported enum; this is 0x convention

17 files changed, 75 insertions, 73 deletions

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 4cef60172..10e5c2540 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
@@ -2,7 +2,7 @@ import { DataItem } from 'ethereum-types';
 import * as _ from 'lodash';
 
 import { Calldata, CalldataBlock, RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 import { DecodingRules, EncodingRules } from '../utils/rules';
 
 import { DataTypeFactory } from './interfaces';
@@ -25,7 +25,7 @@ export abstract class DataType {
     }
 
     public encode(value: any, rules?: EncodingRules, selector?: string): string {
-        const rules_ = _.isUndefined(rules) ? Constants.DEFAULT_ENCODING_RULES : rules;
+        const rules_ = _.isUndefined(rules) ? constants.DEFAULT_ENCODING_RULES : rules;
         const calldata = new Calldata(rules_);
         if (!_.isUndefined(selector)) {
             calldata.setSelector(selector);
@@ -44,7 +44,7 @@ export abstract class DataType {
         }
         const hasSelector = !_.isUndefined(selector);
         const rawCalldata = new RawCalldata(calldata, hasSelector);
-        const rules_ = _.isUndefined(rules) ? Constants.DEFAULT_DECODING_RULES : rules;
+        const rules_ = _.isUndefined(rules) ? constants.DEFAULT_DECODING_RULES : rules;
         const value = this.generateValue(rawCalldata, rules_);
         return value;
     }
diff --git a/packages/utils/src/abi_encoder/abstract_data_types/types/pointer.ts b/packages/utils/src/abi_encoder/abstract_data_types/types/pointer.ts
index 8e597636b..3d38deb94 100644
--- a/packages/utils/src/abi_encoder/abstract_data_types/types/pointer.ts
+++ b/packages/utils/src/abi_encoder/abstract_data_types/types/pointer.ts
@@ -3,7 +3,7 @@ import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 
 import { CalldataBlock, CalldataBlocks, RawCalldata } from '../../calldata';
-import * as Constants from '../../utils/constants';
+import { constants } from '../../utils/constants';
 import { DecodingRules } from '../../utils/rules';
 
 import { DataType } from '../data_type';
@@ -34,7 +34,7 @@ export abstract class Pointer extends DataType {
     public generateValue(calldata: RawCalldata, rules: DecodingRules): any {
         const destinationOffsetBuf = calldata.popWord();
         const destinationOffsetHex = ethUtil.bufferToHex(destinationOffsetBuf);
-        const destinationOffsetRelative = parseInt(destinationOffsetHex, Constants.HEX_BASE);
+        const destinationOffsetRelative = parseInt(destinationOffsetHex, constants.HEX_BASE);
         const destinationOffsetAbsolute = calldata.toAbsoluteOffset(destinationOffsetRelative);
         const currentOffset = calldata.getOffset();
         calldata.setOffset(destinationOffsetAbsolute);
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 aeea7919f..f50ed8298 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
@@ -4,7 +4,7 @@ import * as _ from 'lodash';
 
 import { BigNumber } from '../../../configured_bignumber';
 import { CalldataBlock, CalldataBlocks, RawCalldata } from '../../calldata';
-import * as Constants from '../../utils/constants';
+import { constants } from '../../utils/constants';
 import { DecodingRules } from '../../utils/rules';
 
 import { DataType } from '../data_type';
@@ -54,7 +54,7 @@ export abstract class Set extends DataType {
         if (this._isArray && _.isUndefined(this._arrayLength)) {
             const arrayLengthBuf = calldata.popWord();
             const arrayLengthHex = ethUtil.bufferToHex(arrayLengthBuf);
-            const arrayLength = new BigNumber(arrayLengthHex, Constants.HEX_BASE);
+            const arrayLength = new BigNumber(arrayLengthHex, constants.HEX_BASE);
             [members] = this._createMembersWithLength(this.getDataItem(), arrayLength.toNumber());
         }
         // Create a new scope in the calldata, before descending into the members of this set.
@@ -115,8 +115,8 @@ export abstract class Set extends DataType {
         if (this._isArray && _.isUndefined(this._arrayLength)) {
             [members] = this._createMembersWithLength(this.getDataItem(), value.length);
             const lenBuf = ethUtil.setLengthLeft(
-                ethUtil.toBuffer(`0x${value.length.toString(Constants.HEX_BASE)}`),
-                Constants.EVM_WORD_WIDTH_IN_BYTES,
+                ethUtil.toBuffer(`0x${value.length.toString(constants.HEX_BASE)}`),
+                constants.EVM_WORD_WIDTH_IN_BYTES,
             );
             block.setHeader(lenBuf);
         }
@@ -205,14 +205,14 @@ export abstract class Set extends DataType {
         _.each(range, (idx: number) => {
             const memberDataItem: DataItem = {
                 type: _.isUndefined(this._arrayElementType) ? '' : this._arrayElementType,
-                name: `${dataItem.name}[${idx.toString(Constants.DEC_BASE)}]`,
+                name: `${dataItem.name}[${idx.toString(constants.DEC_BASE)}]`,
             };
             const components = dataItem.components;
             if (!_.isUndefined(components)) {
                 memberDataItem.components = components;
             }
             const memberType = this.getFactory().create(memberDataItem, this);
-            memberIndexByName[idx.toString(Constants.DEC_BASE)] = members.length;
+            memberIndexByName[idx.toString(constants.DEC_BASE)] = members.length;
             members.push(memberType);
         });
         return [members, memberIndexByName];
diff --git a/packages/utils/src/abi_encoder/calldata/blocks/pointer.ts b/packages/utils/src/abi_encoder/calldata/blocks/pointer.ts
index 654cbe26c..1daf33f7e 100644
--- a/packages/utils/src/abi_encoder/calldata/blocks/pointer.ts
+++ b/packages/utils/src/abi_encoder/calldata/blocks/pointer.ts
@@ -1,7 +1,7 @@
 import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 
-import * as Constants from '../../utils/constants';
+import { constants } from '../../utils/constants';
 
 import { CalldataBlock } from '../calldata_block';
 
@@ -29,9 +29,9 @@ export class Pointer extends CalldataBlock {
         const parentOffset = this._parent.getOffsetInBytes();
         const parentHeaderSize = this._parent.getHeaderSizeInBytes();
         const pointer: number = destinationOffset - (parentOffset + parentHeaderSize);
-        const pointerHex = `0x${pointer.toString(Constants.HEX_BASE)}`;
+        const pointerHex = `0x${pointer.toString(constants.HEX_BASE)}`;
         const pointerBuf = ethUtil.toBuffer(pointerHex);
-        const pointerBufPadded = ethUtil.setLengthLeft(pointerBuf, Constants.EVM_WORD_WIDTH_IN_BYTES);
+        const pointerBufPadded = ethUtil.setLengthLeft(pointerBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
         return pointerBufPadded;
     }
 
diff --git a/packages/utils/src/abi_encoder/calldata/calldata.ts b/packages/utils/src/abi_encoder/calldata/calldata.ts
index 6d8814e06..e5858b524 100644
--- a/packages/utils/src/abi_encoder/calldata/calldata.ts
+++ b/packages/utils/src/abi_encoder/calldata/calldata.ts
@@ -1,7 +1,7 @@
 import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 import { EncodingRules } from '../utils/rules';
 
 import * as CalldataBlocks from './blocks';
@@ -31,7 +31,7 @@ export class Calldata {
     public setSelector(selector: string): void {
         if (!_.startsWith(selector, '0x')) {
             throw new Error(`Expected selector to be hex. Missing prefix '0x'`);
-        } else if (selector.length !== Constants.HEX_SELECTOR_LENGTH_IN_CHARS) {
+        } else if (selector.length !== constants.HEX_SELECTOR_LENGTH_IN_CHARS) {
             throw new Error(`Invalid selector '${selector}'`);
         }
         this._selector = selector;
@@ -206,11 +206,11 @@ export class Calldata {
                 lineStr = `\n${offsetStr}${valueStr}${nameStr}`;
             } else {
                 // This block has at least one word of value.
-                offsetStr = `0x${offset.toString(Constants.HEX_BASE)}`.padEnd(offsetPadding);
+                offsetStr = `0x${offset.toString(constants.HEX_BASE)}`.padEnd(offsetPadding);
                 valueStr = ethUtil
                     .stripHexPrefix(
                         ethUtil.bufferToHex(
-                            block.toBuffer().slice(evmWordStartIndex, Constants.EVM_WORD_WIDTH_IN_BYTES),
+                            block.toBuffer().slice(evmWordStartIndex, constants.EVM_WORD_WIDTH_IN_BYTES),
                         ),
                     )
                     .padEnd(valuePadding);
@@ -223,11 +223,11 @@ export class Calldata {
                 }
             }
             // This block has a value that is more than 1 word.
-            for (let j = Constants.EVM_WORD_WIDTH_IN_BYTES; j < size; j += Constants.EVM_WORD_WIDTH_IN_BYTES) {
-                offsetStr = `0x${(offset + j).toString(Constants.HEX_BASE)}`.padEnd(offsetPadding);
+            for (let j = constants.EVM_WORD_WIDTH_IN_BYTES; j < size; j += constants.EVM_WORD_WIDTH_IN_BYTES) {
+                offsetStr = `0x${(offset + j).toString(constants.HEX_BASE)}`.padEnd(offsetPadding);
                 valueStr = ethUtil
                     .stripHexPrefix(
-                        ethUtil.bufferToHex(block.toBuffer().slice(j, j + Constants.EVM_WORD_WIDTH_IN_BYTES)),
+                        ethUtil.bufferToHex(block.toBuffer().slice(j, j + constants.EVM_WORD_WIDTH_IN_BYTES)),
                     )
                     .padEnd(valuePadding);
                 nameStr = ' '.repeat(namePadding);
diff --git a/packages/utils/src/abi_encoder/calldata/raw_calldata.ts b/packages/utils/src/abi_encoder/calldata/raw_calldata.ts
index fbe592fc7..189841989 100644
--- a/packages/utils/src/abi_encoder/calldata/raw_calldata.ts
+++ b/packages/utils/src/abi_encoder/calldata/raw_calldata.ts
@@ -1,7 +1,7 @@
 import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 import { Queue } from '../utils/queue';
 
 export class RawCalldata {
@@ -24,8 +24,8 @@ export class RawCalldata {
         this._offset = RawCalldata._INITIAL_OFFSET;
         // If there's a selector then slice it
         if (hasSelector) {
-            const selectorBuf = this._value.slice(Constants.HEX_SELECTOR_LENGTH_IN_BYTES);
-            this._value = this._value.slice(Constants.HEX_SELECTOR_LENGTH_IN_BYTES);
+            const selectorBuf = this._value.slice(constants.HEX_SELECTOR_LENGTH_IN_BYTES);
+            this._value = this._value.slice(constants.HEX_SELECTOR_LENGTH_IN_BYTES);
             this._selector = ethUtil.bufferToHex(selectorBuf);
         }
     }
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 07a0bd10c..c45355639 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/address.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/address.ts
@@ -4,12 +4,12 @@ import * as _ from 'lodash';
 
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
 import { RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 
 export class Address extends AbstractDataTypes.Blob {
     private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
     private static readonly _ADDRESS_SIZE_IN_BYTES = 20;
-    private static readonly _DECODED_ADDRESS_OFFSET_IN_BYTES = Constants.EVM_WORD_WIDTH_IN_BYTES -
+    private static readonly _DECODED_ADDRESS_OFFSET_IN_BYTES = constants.EVM_WORD_WIDTH_IN_BYTES -
     Address._ADDRESS_SIZE_IN_BYTES;
 
     public static matchType(type: string): boolean {
@@ -30,7 +30,7 @@ export class Address extends AbstractDataTypes.Blob {
             throw new Error(`Invalid address: '${value}'`);
         }
         const valueBuf = ethUtil.toBuffer(value);
-        const encodedValueBuf = ethUtil.setLengthLeft(valueBuf, Constants.EVM_WORD_WIDTH_IN_BYTES);
+        const encodedValueBuf = ethUtil.setLengthLeft(valueBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
         return encodedValueBuf;
     }
 
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 a86283c2a..272cc4132 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/array.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/array.ts
@@ -2,7 +2,7 @@ import { DataItem } from 'ethereum-types';
 import * as _ from 'lodash';
 
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 
 export class Array extends AbstractDataTypes.Set {
     private static readonly _MATCHER = RegExp('^(.+)\\[([0-9]*)\\]$');
@@ -23,7 +23,7 @@ export class Array extends AbstractDataTypes.Set {
             throw new Error(`Could not parse array length: ${type}`);
         }
         const arrayElementType = matches[1];
-        const arrayLength = _.isEmpty(matches[2]) ? undefined : parseInt(matches[2], Constants.DEC_BASE);
+        const arrayLength = _.isEmpty(matches[2]) ? undefined : parseInt(matches[2], constants.DEC_BASE);
         return [arrayElementType, arrayLength];
     }
 
diff --git a/packages/utils/src/abi_encoder/evm_data_types/bool.ts b/packages/utils/src/abi_encoder/evm_data_types/bool.ts
index 7af13506b..0c29f690a 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/bool.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/bool.ts
@@ -5,7 +5,7 @@ import * as _ from 'lodash';
 import { BigNumber } from '../../configured_bignumber';
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
 import { RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 
 export class Bool extends AbstractDataTypes.Blob {
     private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
@@ -27,7 +27,7 @@ export class Bool extends AbstractDataTypes.Blob {
         const encodedValue = value ? '0x1' : '0x0';
         const encodedValueBuf = ethUtil.setLengthLeft(
             ethUtil.toBuffer(encodedValue),
-            Constants.EVM_WORD_WIDTH_IN_BYTES,
+            constants.EVM_WORD_WIDTH_IN_BYTES,
         );
         return encodedValueBuf;
     }
@@ -35,7 +35,7 @@ export class Bool extends AbstractDataTypes.Blob {
     public decodeValue(calldata: RawCalldata): boolean {
         const valueBuf = calldata.popWord();
         const valueHex = ethUtil.bufferToHex(valueBuf);
-        const valueNumber = new BigNumber(valueHex, Constants.HEX_BASE);
+        const valueNumber = new BigNumber(valueHex, constants.HEX_BASE);
         if (!(valueNumber.equals(0) || valueNumber.equals(1))) {
             throw new Error(`Failed to decode boolean. Expected 0x0 or 0x1, got ${valueHex}`);
         }
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 ac2a1fb6e..2c256cfa9 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
@@ -4,7 +4,7 @@ import * as _ from 'lodash';
 
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
 import { RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 
 export class DynamicBytes extends AbstractDataTypes.Blob {
     private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = false;
@@ -37,10 +37,10 @@ export class DynamicBytes extends AbstractDataTypes.Blob {
         // Encoded value is of the form: <length><value>, with each field padded to be word-aligned.
         // 1/3 Construct the length
         const valueBuf = ethUtil.toBuffer(value);
-        const wordsToStoreValuePadded = Math.ceil(valueBuf.byteLength / Constants.EVM_WORD_WIDTH_IN_BYTES);
-        const bytesToStoreValuePadded = wordsToStoreValuePadded * Constants.EVM_WORD_WIDTH_IN_BYTES;
+        const wordsToStoreValuePadded = Math.ceil(valueBuf.byteLength / constants.EVM_WORD_WIDTH_IN_BYTES);
+        const bytesToStoreValuePadded = wordsToStoreValuePadded * constants.EVM_WORD_WIDTH_IN_BYTES;
         const lengthBuf = ethUtil.toBuffer(valueBuf.byteLength);
-        const lengthBufPadded = ethUtil.setLengthLeft(lengthBuf, Constants.EVM_WORD_WIDTH_IN_BYTES);
+        const lengthBufPadded = ethUtil.setLengthLeft(lengthBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
         // 2/3 Construct the value
         DynamicBytes._sanityCheckValue(value);
         const valueBufPadded = ethUtil.setLengthRight(valueBuf, bytesToStoreValuePadded);
@@ -54,9 +54,9 @@ export class DynamicBytes extends AbstractDataTypes.Blob {
         // 1/2 Decode length
         const lengthBuf = calldata.popWord();
         const lengthHex = ethUtil.bufferToHex(lengthBuf);
-        const length = parseInt(lengthHex, Constants.HEX_BASE);
+        const length = parseInt(lengthHex, constants.HEX_BASE);
         // 2/2 Decode value
-        const wordsToStoreValuePadded = Math.ceil(length / Constants.EVM_WORD_WIDTH_IN_BYTES);
+        const wordsToStoreValuePadded = Math.ceil(length / constants.EVM_WORD_WIDTH_IN_BYTES);
         const valueBufPadded = calldata.popWords(wordsToStoreValuePadded);
         const valueBuf = valueBufPadded.slice(0, length);
         const value = ethUtil.bufferToHex(valueBuf);
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 3e465fc15..244b720e3 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/int.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/int.ts
@@ -4,7 +4,7 @@ import * as _ from 'lodash';
 import { BigNumber } from '../../configured_bignumber';
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
 import { RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 import * as EncoderMath from '../utils/math';
 
 export class Int extends AbstractDataTypes.Blob {
@@ -26,7 +26,7 @@ export class Int extends AbstractDataTypes.Blob {
         const matches = Int._MATCHER.exec(type);
         const width =
             !_.isNull(matches) && matches.length === 2 && !_.isUndefined(matches[1])
-                ? parseInt(matches[1], Constants.DEC_BASE)
+                ? parseInt(matches[1], constants.DEC_BASE)
                 : Int._DEFAULT_WIDTH;
         return 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 bd4732097..7256a93d9 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/method.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/method.ts
@@ -3,7 +3,7 @@ import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 
 import { AbstractDataTypes, DataType, DataTypeFactory } from '../abstract_data_types';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 import { DecodingRules, EncodingRules } from '../utils/rules';
 
 import { Tuple } from './tuple';
@@ -62,7 +62,7 @@ export class Method extends AbstractDataTypes.Set {
             ethUtil.toBuffer(
                 ethUtil
                     .sha3(signature)
-                    .slice(Constants.HEX_SELECTOR_BYTE_OFFSET_IN_CALLDATA, Constants.HEX_SELECTOR_LENGTH_IN_BYTES),
+                    .slice(constants.HEX_SELECTOR_BYTE_OFFSET_IN_CALLDATA, constants.HEX_SELECTOR_LENGTH_IN_BYTES),
             ),
         );
         return selector;
diff --git a/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts b/packages/utils/src/abi_encoder/evm_data_types/static_bytes.ts
index ed1f51f7e..5453d47a0 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
@@ -4,7 +4,7 @@ import * as _ from 'lodash';
 
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
 import { RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 
 export class StaticBytes extends AbstractDataTypes.Blob {
     private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = true;
@@ -22,7 +22,7 @@ export class StaticBytes extends AbstractDataTypes.Blob {
         const matches = StaticBytes._MATCHER.exec(type);
         const width =
             !_.isNull(matches) && matches.length === 3 && !_.isUndefined(matches[2])
-                ? parseInt(matches[2], Constants.DEC_BASE)
+                ? parseInt(matches[2], constants.DEC_BASE)
                 : StaticBytes._DEFAULT_WIDTH;
         return width;
     }
@@ -45,7 +45,7 @@ export class StaticBytes extends AbstractDataTypes.Blob {
         this._sanityCheckValue(value);
         const valueBuf = ethUtil.toBuffer(value);
         // 2/2 Store value as hex
-        const valuePadded = ethUtil.setLengthRight(valueBuf, Constants.EVM_WORD_WIDTH_IN_BYTES);
+        const valuePadded = ethUtil.setLengthRight(valueBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
         return valuePadded;
     }
 
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 e5b2d5f33..ac62ea264 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/string.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/string.ts
@@ -4,7 +4,7 @@ import * as _ from 'lodash';
 
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
 import { RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 
 export class String extends AbstractDataTypes.Blob {
     private static readonly _SIZE_KNOWN_AT_COMPILE_TIME: boolean = false;
@@ -25,10 +25,10 @@ export class String extends AbstractDataTypes.Blob {
     public encodeValue(value: string): Buffer {
         // Encoded value is of the form: <length><value>, with each field padded to be word-aligned.
         // 1/3 Construct the length
-        const wordsToStoreValuePadded = Math.ceil(value.length / Constants.EVM_WORD_WIDTH_IN_BYTES);
-        const bytesToStoreValuePadded = wordsToStoreValuePadded * Constants.EVM_WORD_WIDTH_IN_BYTES;
+        const wordsToStoreValuePadded = Math.ceil(value.length / constants.EVM_WORD_WIDTH_IN_BYTES);
+        const bytesToStoreValuePadded = wordsToStoreValuePadded * constants.EVM_WORD_WIDTH_IN_BYTES;
         const lengthBuf = ethUtil.toBuffer(value.length);
-        const lengthBufPadded = ethUtil.setLengthLeft(lengthBuf, Constants.EVM_WORD_WIDTH_IN_BYTES);
+        const lengthBufPadded = ethUtil.setLengthLeft(lengthBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
         // 2/3 Construct the value
         const valueBuf = new Buffer(value);
         const valueBufPadded = ethUtil.setLengthRight(valueBuf, bytesToStoreValuePadded);
@@ -42,9 +42,9 @@ export class String extends AbstractDataTypes.Blob {
         // 1/2 Decode length
         const lengthBufPadded = calldata.popWord();
         const lengthHexPadded = ethUtil.bufferToHex(lengthBufPadded);
-        const length = parseInt(lengthHexPadded, Constants.HEX_BASE);
+        const length = parseInt(lengthHexPadded, constants.HEX_BASE);
         // 2/2 Decode value
-        const wordsToStoreValuePadded = Math.ceil(length / Constants.EVM_WORD_WIDTH_IN_BYTES);
+        const wordsToStoreValuePadded = Math.ceil(length / constants.EVM_WORD_WIDTH_IN_BYTES);
         const valueBufPadded = calldata.popWords(wordsToStoreValuePadded);
         const valueBuf = valueBufPadded.slice(0, length);
         const value = valueBuf.toString('ascii');
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 970400a57..df7ea38a4 100644
--- a/packages/utils/src/abi_encoder/evm_data_types/uint.ts
+++ b/packages/utils/src/abi_encoder/evm_data_types/uint.ts
@@ -4,7 +4,7 @@ import * as _ from 'lodash';
 import { BigNumber } from '../../configured_bignumber';
 import { AbstractDataTypes, DataTypeFactory } from '../abstract_data_types';
 import { RawCalldata } from '../calldata';
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 import * as EncoderMath from '../utils/math';
 
 export class UInt extends AbstractDataTypes.Blob {
@@ -26,7 +26,7 @@ export class UInt extends AbstractDataTypes.Blob {
         const matches = UInt._MATCHER.exec(type);
         const width =
             !_.isNull(matches) && matches.length === 2 && !_.isUndefined(matches[1])
-                ? parseInt(matches[1], Constants.DEC_BASE)
+                ? parseInt(matches[1], constants.DEC_BASE)
                 : UInt._DEFAULT_WIDTH;
         return width;
     }
diff --git a/packages/utils/src/abi_encoder/utils/constants.ts b/packages/utils/src/abi_encoder/utils/constants.ts
index 05c6783e7..82eeab010 100644
--- a/packages/utils/src/abi_encoder/utils/constants.ts
+++ b/packages/utils/src/abi_encoder/utils/constants.ts
@@ -1,12 +1,14 @@
 import { DecodingRules, EncodingRules } from './rules';
 
-export const EVM_WORD_WIDTH_IN_BYTES = 32;
-export const EVM_WORD_WIDTH_IN_BITS = 256;
-export const HEX_BASE = 16;
-export const DEC_BASE = 10;
-export const BIN_BASE = 2;
-export const HEX_SELECTOR_LENGTH_IN_CHARS = 10;
-export const HEX_SELECTOR_LENGTH_IN_BYTES = 4;
-export const HEX_SELECTOR_BYTE_OFFSET_IN_CALLDATA = 0;
-export const DEFAULT_DECODING_RULES: DecodingRules = { structsAsObjects: false };
-export const DEFAULT_ENCODING_RULES: EncodingRules = { optimize: false, annotate: false };
+export const constants = {
+    EVM_WORD_WIDTH_IN_BYTES: 32,
+    EVM_WORD_WIDTH_IN_BITS: 256,
+    HEX_BASE: 16,
+    DEC_BASE: 10,
+    BIN_BASE: 2,
+    HEX_SELECTOR_LENGTH_IN_CHARS: 10,
+    HEX_SELECTOR_LENGTH_IN_BYTES: 4,
+    HEX_SELECTOR_BYTE_OFFSET_IN_CALLDATA: 0,
+    DEFAULT_DECODING_RULES: { structsAsObjects: false } as DecodingRules,
+    DEFAULT_ENCODING_RULES: { optimize: false, annotate: false } as EncodingRules,
+};
diff --git a/packages/utils/src/abi_encoder/utils/math.ts b/packages/utils/src/abi_encoder/utils/math.ts
index 9bcdc3af1..d84983c5b 100644
--- a/packages/utils/src/abi_encoder/utils/math.ts
+++ b/packages/utils/src/abi_encoder/utils/math.ts
@@ -2,7 +2,7 @@ import BigNumber from 'bignumber.js';
 import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 
-import * as Constants from '../utils/constants';
+import { constants } from '../utils/constants';
 
 function sanityCheckBigNumberRange(
     value_: BigNumber | string | number,
@@ -17,9 +17,9 @@ function sanityCheckBigNumberRange(
     }
 }
 function bigNumberToPaddedBuffer(value: BigNumber): Buffer {
-    const valueHex = `0x${value.toString(Constants.HEX_BASE)}`;
+    const valueHex = `0x${value.toString(constants.HEX_BASE)}`;
     const valueBuf = ethUtil.toBuffer(valueHex);
-    const valueBufPadded = ethUtil.setLengthLeft(valueBuf, Constants.EVM_WORD_WIDTH_IN_BYTES);
+    const valueBufPadded = ethUtil.setLengthLeft(valueBuf, constants.EVM_WORD_WIDTH_IN_BYTES);
     return valueBufPadded;
 }
 /**
@@ -37,13 +37,13 @@ export function encodeNumericValue(value_: BigNumber | string | number): Buffer
     // Case 2/2: Value is negative
     // Use two's-complement to encode the value
     // Step 1/3: Convert negative value to positive binary string
-    const valueBin = value.times(-1).toString(Constants.BIN_BASE);
+    const valueBin = value.times(-1).toString(constants.BIN_BASE);
     // Step 2/3: Invert binary value
-    let invertedValueBin = '1'.repeat(Constants.EVM_WORD_WIDTH_IN_BITS - valueBin.length);
+    let invertedValueBin = '1'.repeat(constants.EVM_WORD_WIDTH_IN_BITS - valueBin.length);
     _.each(valueBin, (bit: string) => {
         invertedValueBin += bit === '1' ? '0' : '1';
     });
-    const invertedValue = new BigNumber(invertedValueBin, Constants.BIN_BASE);
+    const invertedValue = new BigNumber(invertedValueBin, constants.BIN_BASE);
     // Step 3/3: Add 1 to inverted value
     const negativeValue = invertedValue.plus(1);
     const encodedValue = bigNumberToPaddedBuffer(negativeValue);
@@ -73,13 +73,13 @@ export function safeEncodeNumericValue(
 export function decodeNumericValue(encodedValue: Buffer, minValue: BigNumber): BigNumber {
     const valueHex = ethUtil.bufferToHex(encodedValue);
     // Case 1/3: value is definitely non-negative because of numeric boundaries
-    const value = new BigNumber(valueHex, Constants.HEX_BASE);
+    const value = new BigNumber(valueHex, constants.HEX_BASE);
     if (!minValue.lessThan(0)) {
         return value;
     }
     // Case 2/3: value is non-negative because there is no leading 1 (encoded as two's-complement)
-    const valueBin = value.toString(Constants.BIN_BASE);
-    const isValueNegative = valueBin.length === Constants.EVM_WORD_WIDTH_IN_BITS && _.startsWith(valueBin[0], '1');
+    const valueBin = value.toString(constants.BIN_BASE);
+    const isValueNegative = valueBin.length === constants.EVM_WORD_WIDTH_IN_BITS && _.startsWith(valueBin[0], '1');
     if (!isValueNegative) {
         return value;
     }
@@ -89,7 +89,7 @@ export function decodeNumericValue(encodedValue: Buffer, minValue: BigNumber): B
     _.each(valueBin, (bit: string) => {
         invertedValueBin += bit === '1' ? '0' : '1';
     });
-    const invertedValue = new BigNumber(invertedValueBin, Constants.BIN_BASE);
+    const invertedValue = new BigNumber(invertedValueBin, constants.BIN_BASE);
     // Step 2/3: Add 1 to inverted value
     // The result is the two's-complement representation of the input value.
     const positiveValue = invertedValue.plus(1);