Merge branch 'development' into dev-section-redesign

* development: (62 commits)
  Fix linter error
  Upgrade ethereum-types
  Lint and update deps
  Be more explicit with falsiness
  Add type to cssRuleIfExists
  Fix issue where we throw if non-numeric characters are used in input
  Upgrade to more recent types, fix yarn.lock
  [fix]: [testnet-faucet] Exit 1 on build fail
  Explains tools we want them to use
  Add note about button
  Add dev-tools-pages bundles to gitignore
  Improve README
  Fix button and center
  Increase max bundle size for instant
  Add stuff
  Initial project scaffolding
  Change tslint config to remove conflicts with prettier
  fix: [testnet-faucet] Signing of orders
  Update the CHANGELOG
  Add comments for expiryBuffer
  ...

12 files changed, 429 insertions, 314 deletions

diff --git a/packages/order-utils/CHANGELOG.json b/packages/order-utils/CHANGELOG.json
index 3e841c43c..5a0c0db47 100644
--- a/packages/order-utils/CHANGELOG.json
+++ b/packages/order-utils/CHANGELOG.json
@@ -1,5 +1,23 @@
 [
     {
+        "version": "2.0.0",
+        "changes": [
+            {
+                "note":
+                    "Added `ecSignOrderAsync` to first sign an order using `eth_signTypedData` and fallback to `eth_sign`.",
+                "pr": 1102
+            },
+            {
+                "note": "Added `ecSignTypedDataOrderAsync` to sign an order exclusively using `eth_signTypedData`.",
+                "pr": 1102
+            },
+            {
+                "note": "Rename `ecSignOrderHashAsync` to `ecSignHashAsync` removing `SignerType` parameter.",
+                "pr": 1102
+            }
+        ]
+    },
+    {
         "version": "1.0.7",
         "changes": [
             {
diff --git a/packages/order-utils/package.json b/packages/order-utils/package.json
index 23ed9ca12..6471de9f5 100644
--- a/packages/order-utils/package.json
+++ b/packages/order-utils/package.json
@@ -70,7 +70,7 @@
         "ethereum-types": "^1.0.11",
         "ethereumjs-abi": "0.6.5",
         "ethereumjs-util": "^5.1.1",
-        "ethers": "4.0.0-beta.14",
+        "ethers": "~4.0.4",
         "lodash": "^4.17.5"
     },
     "publishConfig": {
diff --git a/packages/order-utils/src/constants.ts b/packages/order-utils/src/constants.ts
index c23578c20..7de20a696 100644
--- a/packages/order-utils/src/constants.ts
+++ b/packages/order-utils/src/constants.ts
@@ -13,4 +13,39 @@ export const constants = {
     BASE_16: 16,
     INFINITE_TIMESTAMP_SEC: new BigNumber(2524604400), // Close to infinite
     ZERO_AMOUNT: new BigNumber(0),
+    EIP712_DOMAIN_NAME: '0x Protocol',
+    EIP712_DOMAIN_VERSION: '2',
+    EIP712_DOMAIN_SCHEMA: {
+        name: 'EIP712Domain',
+        parameters: [
+            { name: 'name', type: 'string' },
+            { name: 'version', type: 'string' },
+            { name: 'verifyingContract', type: 'address' },
+        ],
+    },
+    EIP712_ORDER_SCHEMA: {
+        name: 'Order',
+        parameters: [
+            { name: 'makerAddress', type: 'address' },
+            { name: 'takerAddress', type: 'address' },
+            { name: 'feeRecipientAddress', type: 'address' },
+            { name: 'senderAddress', type: 'address' },
+            { name: 'makerAssetAmount', type: 'uint256' },
+            { name: 'takerAssetAmount', type: 'uint256' },
+            { name: 'makerFee', type: 'uint256' },
+            { name: 'takerFee', type: 'uint256' },
+            { name: 'expirationTimeSeconds', type: 'uint256' },
+            { name: 'salt', type: 'uint256' },
+            { name: 'makerAssetData', type: 'bytes' },
+            { name: 'takerAssetData', type: 'bytes' },
+        ],
+    },
+    EIP712_ZEROEX_TRANSACTION_SCHEMA: {
+        name: 'ZeroExTransaction',
+        parameters: [
+            { name: 'salt', type: 'uint256' },
+            { name: 'signerAddress', type: 'address' },
+            { name: 'data', type: 'bytes' },
+        ],
+    },
 };
diff --git a/packages/order-utils/src/eip712_utils.ts b/packages/order-utils/src/eip712_utils.ts
index b303c93dc..56f736500 100644
--- a/packages/order-utils/src/eip712_utils.ts
+++ b/packages/order-utils/src/eip712_utils.ts
@@ -1,109 +1,83 @@
-import ethUtil = require('ethereumjs-util');
+import { assert } from '@0xproject/assert';
+import { schemas } from '@0xproject/json-schemas';
+import { EIP712Object, EIP712TypedData, EIP712Types, Order, ZeroExTransaction } from '@0xproject/types';
 import * as _ from 'lodash';
 
-import { crypto } from './crypto';
-import { EIP712Schema, EIP712Types } from './types';
-
-const EIP191_PREFIX = '\x19\x01';
-const EIP712_DOMAIN_NAME = '0x Protocol';
-const EIP712_DOMAIN_VERSION = '2';
-const EIP712_VALUE_LENGTH = 32;
-
-const EIP712_DOMAIN_SCHEMA: EIP712Schema = {
-    name: 'EIP712Domain',
-    parameters: [
-        { name: 'name', type: EIP712Types.String },
-        { name: 'version', type: EIP712Types.String },
-        { name: 'verifyingContract', type: EIP712Types.Address },
-    ],
-};
+import { constants } from './constants';
 
 export const eip712Utils = {
     /**
-     * Compiles the EIP712Schema and returns the hash of the schema.
-     * @param   schema The EIP712 schema.
-     * @return  The hash of the compiled schema
-     */
-    compileSchema(schema: EIP712Schema): Buffer {
-        const eip712Schema = eip712Utils._encodeType(schema);
-        const eip712SchemaHashBuffer = crypto.solSHA3([eip712Schema]);
-        return eip712SchemaHashBuffer;
-    },
-    /**
-     * Merges the EIP712 hash of a struct with the DomainSeparator for 0x v2.
-     * @param   hashStruct the EIP712 hash of a struct
-     * @param   contractAddress the exchange contract address
-     * @return  The hash of an EIP712 message with domain separator prefixed
-     */
-    createEIP712Message(hashStruct: Buffer, contractAddress: string): Buffer {
-        const domainSeparatorHashBuffer = eip712Utils._getDomainSeparatorHashBuffer(contractAddress);
-        const messageBuff = crypto.solSHA3([EIP191_PREFIX, domainSeparatorHashBuffer, hashStruct]);
-        return messageBuff;
-    },
-    /**
-     * Pad an address to 32 bytes
-     * @param address Address to pad
-     * @return padded address
+     * Creates a EIP712TypedData object specific to the 0x protocol for use with signTypedData.
+     * @param   primaryType The primary type found in message
+     * @param   types The additional types for the data in message
+     * @param   message The contents of the message
+     * @param   exchangeAddress The address of the exchange contract
+     * @return  A typed data object
      */
-    pad32Address(address: string): Buffer {
-        const addressBuffer = ethUtil.toBuffer(address);
-        const addressPadded = eip712Utils.pad32Buffer(addressBuffer);
-        return addressPadded;
+    createTypedData: (
+        primaryType: string,
+        types: EIP712Types,
+        message: EIP712Object,
+        exchangeAddress: string,
+    ): EIP712TypedData => {
+        assert.isETHAddressHex('exchangeAddress', exchangeAddress);
+        assert.isString('primaryType', primaryType);
+        const typedData = {
+            types: {
+                EIP712Domain: constants.EIP712_DOMAIN_SCHEMA.parameters,
+                ...types,
+            },
+            domain: {
+                name: constants.EIP712_DOMAIN_NAME,
+                version: constants.EIP712_DOMAIN_VERSION,
+                verifyingContract: exchangeAddress,
+            },
+            message,
+            primaryType,
+        };
+        assert.doesConformToSchema('typedData', typedData, schemas.eip712TypedDataSchema);
+        return typedData;
     },
     /**
-     * Pad an buffer to 32 bytes
-     * @param buffer Address to pad
-     * @return padded buffer
+     * Creates an Order EIP712TypedData object for use with signTypedData.
+     * @param   Order the order
+     * @return  A typed data object
      */
-    pad32Buffer(buffer: Buffer): Buffer {
-        const bufferPadded = ethUtil.setLengthLeft(buffer, EIP712_VALUE_LENGTH);
-        return bufferPadded;
+    createOrderTypedData: (order: Order): EIP712TypedData => {
+        assert.doesConformToSchema('order', order, schemas.orderSchema, [schemas.hexSchema]);
+        const normalizedOrder = _.mapValues(order, value => {
+            return !_.isString(value) ? value.toString() : value;
+        });
+        const typedData = eip712Utils.createTypedData(
+            constants.EIP712_ORDER_SCHEMA.name,
+            { Order: constants.EIP712_ORDER_SCHEMA.parameters },
+            normalizedOrder,
+            order.exchangeAddress,
+        );
+        return typedData;
     },
     /**
-     * Hash together a EIP712 schema with the corresponding data
-     * @param schema EIP712-compliant schema
-     * @param data Data the complies to the schema
-     * @return A buffer containing the SHA256 hash of the schema and encoded data
+     * Creates an ExecuteTransaction EIP712TypedData object for use with signTypedData and
+     * 0x Exchange executeTransaction.
+     * @param   ZeroExTransaction the 0x transaction
+     * @param   exchangeAddress The address of the exchange contract
+     * @return  A typed data object
      */
-    structHash(schema: EIP712Schema, data: { [key: string]: any }): Buffer {
-        const encodedData = eip712Utils._encodeData(schema, data);
-        const schemaHash = eip712Utils.compileSchema(schema);
-        const hashBuffer = crypto.solSHA3([schemaHash, ...encodedData]);
-        return hashBuffer;
-    },
-    _getDomainSeparatorSchemaBuffer(): Buffer {
-        return eip712Utils.compileSchema(EIP712_DOMAIN_SCHEMA);
-    },
-    _getDomainSeparatorHashBuffer(exchangeAddress: string): Buffer {
-        const domainSeparatorSchemaBuffer = eip712Utils._getDomainSeparatorSchemaBuffer();
-        const encodedData = eip712Utils._encodeData(EIP712_DOMAIN_SCHEMA, {
-            name: EIP712_DOMAIN_NAME,
-            version: EIP712_DOMAIN_VERSION,
-            verifyingContract: exchangeAddress,
+    createZeroExTransactionTypedData: (
+        zeroExTransaction: ZeroExTransaction,
+        exchangeAddress: string,
+    ): EIP712TypedData => {
+        assert.isETHAddressHex('exchangeAddress', exchangeAddress);
+        assert.doesConformToSchema('zeroExTransaction', zeroExTransaction, schemas.zeroExTransactionSchema);
+        const normalizedTransaction = _.mapValues(zeroExTransaction, value => {
+            return !_.isString(value) ? value.toString() : value;
         });
-        const domainSeparatorHashBuff2 = crypto.solSHA3([domainSeparatorSchemaBuffer, ...encodedData]);
-        return domainSeparatorHashBuff2;
-    },
-    _encodeType(schema: EIP712Schema): string {
-        const namedTypes = _.map(schema.parameters, ({ name, type }) => `${type} ${name}`);
-        const namedTypesJoined = namedTypes.join(',');
-        const encodedType = `${schema.name}(${namedTypesJoined})`;
-        return encodedType;
-    },
-    _encodeData(schema: EIP712Schema, data: { [key: string]: any }): any {
-        const encodedValues = [];
-        for (const parameter of schema.parameters) {
-            const value = data[parameter.name];
-            if (parameter.type === EIP712Types.String || parameter.type === EIP712Types.Bytes) {
-                encodedValues.push(crypto.solSHA3([ethUtil.toBuffer(value)]));
-            } else if (parameter.type === EIP712Types.Uint256) {
-                encodedValues.push(value);
-            } else if (parameter.type === EIP712Types.Address) {
-                encodedValues.push(eip712Utils.pad32Address(value));
-            } else {
-                throw new Error(`Unable to encode ${parameter.type}`);
-            }
-        }
-        return encodedValues;
+        const typedData = eip712Utils.createTypedData(
+            constants.EIP712_ZEROEX_TRANSACTION_SCHEMA.name,
+            { ZeroExTransaction: constants.EIP712_ZEROEX_TRANSACTION_SCHEMA.parameters },
+            normalizedTransaction,
+            exchangeAddress,
+        );
+        return typedData;
     },
 };
diff --git a/packages/order-utils/src/index.ts b/packages/order-utils/src/index.ts
index 1553647c6..dbb782b85 100644
--- a/packages/order-utils/src/index.ts
+++ b/packages/order-utils/src/index.ts
@@ -2,7 +2,6 @@ export { orderHashUtils } from './order_hash';
 export { signatureUtils } from './signature_utils';
 export { generatePseudoRandomSalt } from './salt';
 export { assetDataUtils } from './asset_data_utils';
-export { eip712Utils } from './eip712_utils';
 export { marketUtils } from './market_utils';
 export { rateUtils } from './rate_utils';
 export { sortingUtils } from './sorting_utils';
@@ -19,7 +18,17 @@ export { ExchangeTransferSimulator } from './exchange_transfer_simulator';
 export { BalanceAndProxyAllowanceLazyStore } from './store/balance_and_proxy_allowance_lazy_store';
 export { OrderFilledCancelledLazyStore } from './store/order_filled_cancelled_lazy_store';
 
-export { Provider, JSONRPCRequestPayload, JSONRPCErrorCallback, JSONRPCResponsePayload } from 'ethereum-types';
+export { constants } from './constants';
+export { eip712Utils } from './eip712_utils';
+
+export {
+    Provider,
+    JSONRPCRequestPayload,
+    JSONRPCErrorCallback,
+    JSONRPCResponsePayload,
+    JSONRPCResponseError,
+} from 'ethereum-types';
+
 export {
     SignedOrder,
     Order,
@@ -29,17 +38,19 @@ export {
     ERC20AssetData,
     ERC721AssetData,
     AssetProxyId,
-    SignerType,
     SignatureType,
     OrderStateValid,
     OrderStateInvalid,
     ExchangeContractErrs,
+    EIP712Parameter,
+    EIP712TypedData,
+    EIP712Types,
+    EIP712Object,
+    EIP712ObjectValue,
+    ZeroExTransaction,
 } from '@0xproject/types';
 export {
     OrderError,
-    EIP712Parameter,
-    EIP712Schema,
-    EIP712Types,
     TradeSide,
     TransferType,
     FindFeeOrdersThatCoverFeesForTargetOrdersOpts,
diff --git a/packages/order-utils/src/order_factory.ts b/packages/order-utils/src/order_factory.ts
index b1292903a..0f0cd6046 100644
--- a/packages/order-utils/src/order_factory.ts
+++ b/packages/order-utils/src/order_factory.ts
@@ -1,4 +1,4 @@
-import { Order, SignedOrder, SignerType } from '@0xproject/types';
+import { Order, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Provider } from 'ethereum-types';
 import * as _ from 'lodash';
@@ -71,12 +71,7 @@ export const orderFactory = {
             createOrderOpts,
         );
         const orderHash = orderHashUtils.getOrderHashHex(order);
-        const signature = await signatureUtils.ecSignOrderHashAsync(
-            provider,
-            orderHash,
-            makerAddress,
-            SignerType.Default,
-        );
+        const signature = await signatureUtils.ecSignHashAsync(provider, orderHash, makerAddress);
         const signedOrder: SignedOrder = _.assign(order, { signature });
         return signedOrder;
     },
diff --git a/packages/order-utils/src/order_hash.ts b/packages/order-utils/src/order_hash.ts
index 8e98f8767..b523a3523 100644
--- a/packages/order-utils/src/order_hash.ts
+++ b/packages/order-utils/src/order_hash.ts
@@ -1,31 +1,13 @@
 import { schemas, SchemaValidator } from '@0xproject/json-schemas';
 import { Order, SignedOrder } from '@0xproject/types';
+import { signTypedDataUtils } from '@0xproject/utils';
 import * as _ from 'lodash';
 
 import { assert } from './assert';
 import { eip712Utils } from './eip712_utils';
-import { EIP712Schema, EIP712Types } from './types';
 
 const INVALID_TAKER_FORMAT = 'instance.takerAddress is not of a type(s) string';
 
-const EIP712_ORDER_SCHEMA: EIP712Schema = {
-    name: 'Order',
-    parameters: [
-        { name: 'makerAddress', type: EIP712Types.Address },
-        { name: 'takerAddress', type: EIP712Types.Address },
-        { name: 'feeRecipientAddress', type: EIP712Types.Address },
-        { name: 'senderAddress', type: EIP712Types.Address },
-        { name: 'makerAssetAmount', type: EIP712Types.Uint256 },
-        { name: 'takerAssetAmount', type: EIP712Types.Uint256 },
-        { name: 'makerFee', type: EIP712Types.Uint256 },
-        { name: 'takerFee', type: EIP712Types.Uint256 },
-        { name: 'expirationTimeSeconds', type: EIP712Types.Uint256 },
-        { name: 'salt', type: EIP712Types.Uint256 },
-        { name: 'makerAssetData', type: EIP712Types.Bytes },
-        { name: 'takerAssetData', type: EIP712Types.Bytes },
-    ],
-};
-
 export const orderHashUtils = {
     /**
      * Checks if the supplied hex encoded order hash is valid.
@@ -45,7 +27,7 @@ export const orderHashUtils = {
     /**
      * Computes the orderHash for a supplied order.
      * @param   order   An object that conforms to the Order or SignedOrder interface definitions.
-     * @return  The resulting orderHash from hashing the supplied order.
+     * @return  Hex encoded string orderHash from hashing the supplied order.
      */
     getOrderHashHex(order: SignedOrder | Order): string {
         try {
@@ -64,16 +46,13 @@ export const orderHashUtils = {
         return orderHashHex;
     },
     /**
-     * Computes the orderHash for a supplied order and returns it as a Buffer
+     * Computes the orderHash for a supplied order
      * @param   order   An object that conforms to the Order or SignedOrder interface definitions.
-     * @return  The resulting orderHash from hashing the supplied order as a Buffer
+     * @return  A Buffer containing the resulting orderHash from hashing the supplied order
      */
     getOrderHashBuffer(order: SignedOrder | Order): Buffer {
-        const orderParamsHashBuff = eip712Utils.structHash(EIP712_ORDER_SCHEMA, order);
-        const orderHashBuff = eip712Utils.createEIP712Message(orderParamsHashBuff, order.exchangeAddress);
+        const typedData = eip712Utils.createOrderTypedData(order);
+        const orderHashBuff = signTypedDataUtils.generateTypedDataHash(typedData);
         return orderHashBuff;
     },
-    _getOrderSchemaBuffer(): Buffer {
-        return eip712Utils.compileSchema(EIP712_ORDER_SCHEMA);
-    },
 };
diff --git a/packages/order-utils/src/signature_utils.ts b/packages/order-utils/src/signature_utils.ts
index 3b656d3fc..372d210d0 100644
--- a/packages/order-utils/src/signature_utils.ts
+++ b/packages/order-utils/src/signature_utils.ts
@@ -1,5 +1,5 @@
 import { schemas } from '@0xproject/json-schemas';
-import { ECSignature, SignatureType, SignerType, ValidatorSignature } from '@0xproject/types';
+import { ECSignature, Order, SignatureType, SignedOrder, ValidatorSignature } from '@0xproject/types';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import { Provider } from 'ethereum-types';
 import * as ethUtil from 'ethereumjs-util';
@@ -7,9 +7,11 @@ import * as _ from 'lodash';
 
 import { artifacts } from './artifacts';
 import { assert } from './assert';
+import { eip712Utils } from './eip712_utils';
 import { ExchangeContract } from './generated_contract_wrappers/exchange';
 import { IValidatorContract } from './generated_contract_wrappers/i_validator';
 import { IWalletContract } from './generated_contract_wrappers/i_wallet';
+import { orderHashUtils } from './order_hash';
 import { OrderError } from './types';
 import { utils } from './utils';
 
@@ -49,7 +51,7 @@ export const signatureUtils = {
 
             case SignatureType.EthSign: {
                 const ecSignature = signatureUtils.parseECSignature(signature);
-                const prefixedMessageHex = signatureUtils.addSignedMessagePrefix(data, SignerType.Default);
+                const prefixedMessageHex = signatureUtils.addSignedMessagePrefix(data);
                 return signatureUtils.isValidECSignature(prefixedMessageHex, ecSignature, signerAddress);
             }
 
@@ -192,36 +194,90 @@ export const signatureUtils = {
         }
     },
     /**
-     * Signs an orderHash and returns it's elliptic curve signature and signature type.
-     * This method currently supports TestRPC, Geth and Parity above and below V1.6.6
-     * @param   orderHash       Hex encoded orderHash to sign.
+     * Signs an order and returns a SignedOrder. First `eth_signTypedData` is requested
+     * then a fallback to `eth_sign` if not available on the supplied provider.
+     * @param   order The Order to sign.
      * @param   signerAddress   The hex encoded Ethereum address you wish to sign it with. This address
-     *          must be available via the Provider supplied to 0x.js.
-     * @param   signerType Different signers add/require different prefixes to be prepended to the message being signed.
-     *          Since we cannot know ahead of time which signer you are using, you must supply a SignerType.
-     * @return  A hex encoded string containing the Elliptic curve signature generated by signing the orderHash and the Signature Type.
+     *          must be available via the supplied Provider.
+     * @return  A SignedOrder containing the order and Elliptic curve signature with Signature Type.
      */
-    async ecSignOrderHashAsync(
-        provider: Provider,
-        orderHash: string,
-        signerAddress: string,
-        signerType: SignerType,
-    ): Promise<string> {
+    async ecSignOrderAsync(provider: Provider, order: Order, signerAddress: string): Promise<SignedOrder> {
+        assert.doesConformToSchema('order', order, schemas.orderSchema, [schemas.hexSchema]);
+        try {
+            const signedOrder = await signatureUtils.ecSignTypedDataOrderAsync(provider, order, signerAddress);
+            return signedOrder;
+        } catch (err) {
+            // HACK: We are unable to handle specific errors thrown since provider is not an object
+            //       under our control. It could be Metamask Web3, Ethers, or any general RPC provider.
+            //       We check for a user denying the signature request in a way that supports Metamask and
+            //       Coinbase Wallet. Unfortunately for signers with a different error message,
+            //       they will receive two signature requests.
+            if (err.message.includes('User denied message signature')) {
+                throw err;
+            }
+            const orderHash = orderHashUtils.getOrderHashHex(order);
+            const signatureHex = await signatureUtils.ecSignHashAsync(provider, orderHash, signerAddress);
+            const signedOrder = {
+                ...order,
+                signature: signatureHex,
+            };
+            return signedOrder;
+        }
+    },
+    /**
+     * Signs an order using `eth_signTypedData` and returns a SignedOrder.
+     * @param   order The Order to sign.
+     * @param   signerAddress   The hex encoded Ethereum address you wish to sign it with. This address
+     *          must be available via the supplied Provider.
+     * @return  A SignedOrder containing the order and Elliptic curve signature with Signature Type.
+     */
+    async ecSignTypedDataOrderAsync(provider: Provider, order: Order, signerAddress: string): Promise<SignedOrder> {
         assert.isWeb3Provider('provider', provider);
-        assert.isHexString('orderHash', orderHash);
         assert.isETHAddressHex('signerAddress', signerAddress);
+        assert.doesConformToSchema('order', order, schemas.orderSchema, [schemas.hexSchema]);
         const web3Wrapper = new Web3Wrapper(provider);
         await assert.isSenderAddressAsync('signerAddress', signerAddress, web3Wrapper);
         const normalizedSignerAddress = signerAddress.toLowerCase();
-
-        let msgHashHex = orderHash;
-        const prefixedMsgHashHex = signatureUtils.addSignedMessagePrefix(orderHash, signerType);
-        // Metamask incorrectly implements eth_sign and does not prefix the message as per the spec
-        // Source: https://github.com/MetaMask/metamask-extension/commit/a9d36860bec424dcee8db043d3e7da6a5ff5672e
-        if (signerType === SignerType.Metamask) {
-            msgHashHex = prefixedMsgHashHex;
+        const typedData = eip712Utils.createOrderTypedData(order);
+        try {
+            const signature = await web3Wrapper.signTypedDataAsync(normalizedSignerAddress, typedData);
+            const ecSignatureRSV = parseSignatureHexAsRSV(signature);
+            const signatureBuffer = Buffer.concat([
+                ethUtil.toBuffer(ecSignatureRSV.v),
+                ethUtil.toBuffer(ecSignatureRSV.r),
+                ethUtil.toBuffer(ecSignatureRSV.s),
+                ethUtil.toBuffer(SignatureType.EIP712),
+            ]);
+            const signatureHex = `0x${signatureBuffer.toString('hex')}`;
+            return {
+                ...order,
+                signature: signatureHex,
+            };
+        } catch (err) {
+            // Detect if Metamask to transition users to the MetamaskSubprovider
+            if ((provider as any).isMetaMask) {
+                throw new Error(OrderError.InvalidMetamaskSigner);
+            } else {
+                throw err;
+            }
         }
-        const signature = await web3Wrapper.signMessageAsync(normalizedSignerAddress, msgHashHex);
+    },
+    /**
+     * Signs a hash using `eth_sign` and returns its elliptic curve signature and signature type.
+     * @param   msgHash       Hex encoded message to sign.
+     * @param   signerAddress   The hex encoded Ethereum address you wish to sign it with. This address
+     *          must be available via the supplied Provider.
+     * @return  A hex encoded string containing the Elliptic curve signature generated by signing the msgHash and the Signature Type.
+     */
+    async ecSignHashAsync(provider: Provider, msgHash: string, signerAddress: string): Promise<string> {
+        assert.isWeb3Provider('provider', provider);
+        assert.isHexString('msgHash', msgHash);
+        assert.isETHAddressHex('signerAddress', signerAddress);
+        const web3Wrapper = new Web3Wrapper(provider);
+        await assert.isSenderAddressAsync('signerAddress', signerAddress, web3Wrapper);
+        const normalizedSignerAddress = signerAddress.toLowerCase();
+        const signature = await web3Wrapper.signMessageAsync(normalizedSignerAddress, msgHash);
+        const prefixedMsgHashHex = signatureUtils.addSignedMessagePrefix(msgHash);
 
         // HACK: There is no consensus on whether the signatureHex string should be formatted as
         // v + r + s OR r + s + v, and different clients (even different versions of the same client)
@@ -238,10 +294,7 @@ export const signatureUtils = {
                 normalizedSignerAddress,
             );
             if (isValidRSVSignature) {
-                const convertedSignatureHex = signatureUtils.convertECSignatureToSignatureHex(
-                    ecSignatureRSV,
-                    signerType,
-                );
+                const convertedSignatureHex = signatureUtils.convertECSignatureToSignatureHex(ecSignatureRSV);
                 return convertedSignatureHex;
             }
         }
@@ -253,41 +306,30 @@ export const signatureUtils = {
                 normalizedSignerAddress,
             );
             if (isValidVRSSignature) {
-                const convertedSignatureHex = signatureUtils.convertECSignatureToSignatureHex(
-                    ecSignatureVRS,
-                    signerType,
-                );
+                const convertedSignatureHex = signatureUtils.convertECSignatureToSignatureHex(ecSignatureVRS);
                 return convertedSignatureHex;
             }
         }
-
-        throw new Error(OrderError.InvalidSignature);
+        // Detect if Metamask to transition users to the MetamaskSubprovider
+        if ((provider as any).isMetaMask) {
+            throw new Error(OrderError.InvalidMetamaskSigner);
+        } else {
+            throw new Error(OrderError.InvalidSignature);
+        }
     },
     /**
-     * Combines ECSignature with V,R,S and the relevant signature type for use in 0x protocol
+     * Combines ECSignature with V,R,S and the EthSign signature type for use in 0x protocol
      * @param ecSignature The ECSignature of the signed data
-     * @param signerType The SignerType of the signed data
      * @return Hex encoded string of signature (v,r,s) with Signature Type
      */
-    convertECSignatureToSignatureHex(ecSignature: ECSignature, signerType: SignerType): string {
+    convertECSignatureToSignatureHex(ecSignature: ECSignature): string {
         const signatureBuffer = Buffer.concat([
             ethUtil.toBuffer(ecSignature.v),
             ethUtil.toBuffer(ecSignature.r),
             ethUtil.toBuffer(ecSignature.s),
         ]);
         const signatureHex = `0x${signatureBuffer.toString('hex')}`;
-        let signatureType;
-        switch (signerType) {
-            case SignerType.Metamask:
-            case SignerType.Ledger:
-            case SignerType.Default: {
-                signatureType = SignatureType.EthSign;
-                break;
-            }
-            default:
-                throw new Error(`Unrecognized SignerType: ${signerType}`);
-        }
-        const signatureWithType = signatureUtils.convertToSignatureWithType(signatureHex, signatureType);
+        const signatureWithType = signatureUtils.convertToSignatureWithType(signatureHex, SignatureType.EthSign);
         return signatureWithType;
     },
     /**
@@ -304,28 +346,17 @@ export const signatureUtils = {
     /**
      * Adds the relevant prefix to the message being signed.
      * @param message Message to sign
-     * @param signerType The type of message prefix to add for a given SignerType. Different signers expect
-     *                          specific message prefixes.
      * @return Prefixed message
      */
-    addSignedMessagePrefix(message: string, signerType: SignerType = SignerType.Default): string {
+    addSignedMessagePrefix(message: string): string {
         assert.isString('message', message);
-        assert.doesBelongToStringEnum('signerType', signerType, SignerType);
-        switch (signerType) {
-            case SignerType.Metamask:
-            case SignerType.Ledger:
-            case SignerType.Default: {
-                const msgBuff = ethUtil.toBuffer(message);
-                const prefixedMsgBuff = ethUtil.hashPersonalMessage(msgBuff);
-                const prefixedMsgHex = ethUtil.bufferToHex(prefixedMsgBuff);
-                return prefixedMsgHex;
-            }
-            default:
-                throw new Error(`Unrecognized SignerType: ${signerType}`);
-        }
+        const msgBuff = ethUtil.toBuffer(message);
+        const prefixedMsgBuff = ethUtil.hashPersonalMessage(msgBuff);
+        const prefixedMsgHex = ethUtil.bufferToHex(prefixedMsgBuff);
+        return prefixedMsgHex;
     },
     /**
-     * Parse a 0x protocol hex-encoded signature string into it's ECSignature components
+     * Parse a 0x protocol hex-encoded signature string into its ECSignature components
      * @param signature A hex encoded ecSignature 0x Protocol signature
      * @return An ECSignature object with r,s,v parameters
      */
diff --git a/packages/order-utils/src/types.ts b/packages/order-utils/src/types.ts
index a843efaa4..5b13dd754 100644
--- a/packages/order-utils/src/types.ts
+++ b/packages/order-utils/src/types.ts
@@ -2,6 +2,7 @@ import { BigNumber } from '@0xproject/utils';
 
 export enum OrderError {
     InvalidSignature = 'INVALID_SIGNATURE',
+    InvalidMetamaskSigner = "MetaMask provider must be wrapped in a MetamaskSubprovider (from the '@0xproject/subproviders' package) in order to work with this method.",
 }
 
 export enum TradeSide {
@@ -14,24 +15,6 @@ export enum TransferType {
     Fee = 'fee',
 }
 
-export interface EIP712Parameter {
-    name: string;
-    type: EIP712Types;
-}
-
-export interface EIP712Schema {
-    name: string;
-    parameters: EIP712Parameter[];
-}
-
-export enum EIP712Types {
-    Address = 'address',
-    Bytes = 'bytes',
-    Bytes32 = 'bytes32',
-    String = 'string',
-    Uint256 = 'uint256',
-}
-
 export interface CreateOrderOpts {
     takerAddress?: string;
     senderAddress?: string;
diff --git a/packages/order-utils/test/eip712_utils_test.ts b/packages/order-utils/test/eip712_utils_test.ts
new file mode 100644
index 000000000..d65cabe9c
--- /dev/null
+++ b/packages/order-utils/test/eip712_utils_test.ts
@@ -0,0 +1,44 @@
+import { BigNumber } from '@0xproject/utils';
+import * as chai from 'chai';
+import 'mocha';
+
+import { constants } from '../src/constants';
+import { eip712Utils } from '../src/eip712_utils';
+
+import { chaiSetup } from './utils/chai_setup';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('EIP712 Utils', () => {
+    describe('createTypedData', () => {
+        it('adds in the EIP712DomainSeparator', () => {
+            const primaryType = 'Test';
+            const typedData = eip712Utils.createTypedData(
+                primaryType,
+                { Test: [{ name: 'testValue', type: 'uint256' }] },
+                { testValue: '1' },
+                constants.NULL_ADDRESS,
+            );
+            expect(typedData.domain).to.not.be.undefined();
+            expect(typedData.types.EIP712Domain).to.not.be.undefined();
+            const domainObject = typedData.domain;
+            expect(domainObject.name).to.eq(constants.EIP712_DOMAIN_NAME);
+            expect(typedData.primaryType).to.eq(primaryType);
+        });
+    });
+    describe('createTypedData', () => {
+        it('adds in the EIP712DomainSeparator', () => {
+            const typedData = eip712Utils.createZeroExTransactionTypedData(
+                {
+                    salt: new BigNumber('0'),
+                    data: constants.NULL_BYTES,
+                    signerAddress: constants.NULL_ADDRESS,
+                },
+                constants.NULL_ADDRESS,
+            );
+            expect(typedData.primaryType).to.eq(constants.EIP712_ZEROEX_TRANSACTION_SCHEMA.name);
+            expect(typedData.types.EIP712Domain).to.not.be.undefined();
+        });
+    });
+});
diff --git a/packages/order-utils/test/order_hash_test.ts b/packages/order-utils/test/order_hash_test.ts
index 3fdbbad21..fe44218d6 100644
--- a/packages/order-utils/test/order_hash_test.ts
+++ b/packages/order-utils/test/order_hash_test.ts
@@ -35,6 +35,20 @@ describe('Order hashing', () => {
             const orderHash = orderHashUtils.getOrderHashHex(order);
             expect(orderHash).to.be.equal(expectedOrderHash);
         });
+        it('calculates the order hash if amounts are strings', async () => {
+            // It's common for developers using javascript to provide the amounts
+            // as strings. Since we eventually toString() the BigNumber
+            // before encoding we should result in the same orderHash in this scenario
+            // tslint:disable-next-line:no-unnecessary-type-assertion
+            const orderHash = orderHashUtils.getOrderHashHex({
+                ...order,
+                makerAssetAmount: '0',
+                takerAssetAmount: '0',
+                makerFee: '0',
+                takerFee: '0',
+            } as any);
+            expect(orderHash).to.be.equal(expectedOrderHash);
+        });
         it('throws a readable error message if taker format is invalid', async () => {
             const orderWithInvalidtakerFormat = {
                 ...order,
diff --git a/packages/order-utils/test/signature_utils_test.ts b/packages/order-utils/test/signature_utils_test.ts
index 2ca1109a1..f2d6790fb 100644
--- a/packages/order-utils/test/signature_utils_test.ts
+++ b/packages/order-utils/test/signature_utils_test.ts
@@ -1,12 +1,13 @@
-import { SignerType } from '@0xproject/types';
+import { Order, SignatureType } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
 import { JSONRPCErrorCallback, JSONRPCRequestPayload } from 'ethereum-types';
+import * as ethUtil from 'ethereumjs-util';
 import * as _ from 'lodash';
 import 'mocha';
-import * as Sinon from 'sinon';
 
-import { generatePseudoRandomSalt } from '../src';
+import { generatePseudoRandomSalt, orderHashUtils } from '../src';
+import { constants } from '../src/constants';
 import { signatureUtils } from '../src/signature_utils';
 
 import { chaiSetup } from './utils/chai_setup';
@@ -16,6 +17,28 @@ chaiSetup.configure();
 const expect = chai.expect;
 
 describe('Signature utils', () => {
+    let makerAddress: string;
+    const fakeExchangeContractAddress = '0x1dc4c1cefef38a777b15aa20260a54e584b16c48';
+    let order: Order;
+    before(async () => {
+        const availableAddreses = await web3Wrapper.getAvailableAddressesAsync();
+        makerAddress = availableAddreses[0];
+        order = {
+            makerAddress,
+            takerAddress: constants.NULL_ADDRESS,
+            senderAddress: constants.NULL_ADDRESS,
+            feeRecipientAddress: constants.NULL_ADDRESS,
+            makerAssetData: constants.NULL_ADDRESS,
+            takerAssetData: constants.NULL_ADDRESS,
+            exchangeAddress: fakeExchangeContractAddress,
+            salt: new BigNumber(0),
+            makerFee: new BigNumber(0),
+            takerFee: new BigNumber(0),
+            makerAssetAmount: new BigNumber(0),
+            takerAssetAmount: new BigNumber(0),
+            expirationTimeSeconds: new BigNumber(0),
+        };
+    });
     describe('#isValidSignatureAsync', () => {
         let dataHex = '0x6927e990021d23b1eb7b8789f6a6feaf98fe104bb0cf8259421b79f9a34222b0';
         const ethSignSignature =
@@ -115,28 +138,64 @@ describe('Signature utils', () => {
             expect(salt.lessThan(twoPow256)).to.be.true();
         });
     });
-    describe('#ecSignOrderHashAsync', () => {
-        let stubs: Sinon.SinonStub[] = [];
-        let makerAddress: string;
+    describe('#ecSignOrderAsync', () => {
+        it('should default to eth_sign if eth_signTypedData is unavailable', async () => {
+            const expectedSignature =
+                '0x1c3582f06356a1314dbf1c0e534c4d8e92e59b056ee607a7ff5a825f5f2cc5e6151c5cc7fdd420f5608e4d5bef108e42ad90c7a4b408caef32e24374cf387b0d7603';
+
+            const fakeProvider = {
+                async sendAsync(payload: JSONRPCRequestPayload, callback: JSONRPCErrorCallback): Promise<void> {
+                    if (payload.method === 'eth_signTypedData') {
+                        callback(new Error('Internal RPC Error'));
+                    } else if (payload.method === 'eth_sign') {
+                        const [address, message] = payload.params;
+                        const signature = await web3Wrapper.signMessageAsync(address, message);
+                        callback(null, {
+                            id: 42,
+                            jsonrpc: '2.0',
+                            result: signature,
+                        });
+                    } else {
+                        callback(null, { id: 42, jsonrpc: '2.0', result: [makerAddress] });
+                    }
+                },
+            };
+            const signedOrder = await signatureUtils.ecSignOrderAsync(fakeProvider, order, makerAddress);
+            expect(signedOrder.signature).to.equal(expectedSignature);
+        });
+        it('should throw if the user denies the signing request', async () => {
+            const fakeProvider = {
+                async sendAsync(payload: JSONRPCRequestPayload, callback: JSONRPCErrorCallback): Promise<void> {
+                    if (payload.method === 'eth_signTypedData') {
+                        callback(new Error('User denied message signature'));
+                    } else if (payload.method === 'eth_sign') {
+                        const [address, message] = payload.params;
+                        const signature = await web3Wrapper.signMessageAsync(address, message);
+                        callback(null, {
+                            id: 42,
+                            jsonrpc: '2.0',
+                            result: signature,
+                        });
+                    } else {
+                        callback(null, { id: 42, jsonrpc: '2.0', result: [makerAddress] });
+                    }
+                },
+            };
+            expect(signatureUtils.ecSignOrderAsync(fakeProvider, order, makerAddress)).to.to.be.rejectedWith(
+                'User denied message signature',
+            );
+        });
+    });
+    describe('#ecSignHashAsync', () => {
         before(async () => {
             const availableAddreses = await web3Wrapper.getAvailableAddressesAsync();
             makerAddress = availableAddreses[0];
         });
-        afterEach(() => {
-            // clean up any stubs after the test has completed
-            _.each(stubs, s => s.restore());
-            stubs = [];
-        });
-        it('Should return the correct Signature', async () => {
+        it('should return the correct Signature', async () => {
             const orderHash = '0x6927e990021d23b1eb7b8789f6a6feaf98fe104bb0cf8259421b79f9a34222b0';
             const expectedSignature =
                 '0x1b61a3ed31b43c8780e905a260a35faefcc527be7516aa11c0256729b5b351bc3340349190569279751135161d22529dc25add4f6069af05be04cacbda2ace225403';
-            const ecSignature = await signatureUtils.ecSignOrderHashAsync(
-                provider,
-                orderHash,
-                makerAddress,
-                SignerType.Default,
-            );
+            const ecSignature = await signatureUtils.ecSignHashAsync(provider, orderHash, makerAddress);
             expect(ecSignature).to.equal(expectedSignature);
         });
         it('should return the correct Signature for signatureHex concatenated as R + S + V', async () => {
@@ -162,12 +221,7 @@ describe('Signature utils', () => {
                     }
                 },
             };
-            const ecSignature = await signatureUtils.ecSignOrderHashAsync(
-                fakeProvider,
-                orderHash,
-                makerAddress,
-                SignerType.Default,
-            );
+            const ecSignature = await signatureUtils.ecSignHashAsync(fakeProvider, orderHash, makerAddress);
             expect(ecSignature).to.equal(expectedSignature);
         });
         it('should return the correct Signature for signatureHex concatenated as V + R + S', async () => {
@@ -190,64 +244,68 @@ describe('Signature utils', () => {
                 },
             };
 
-            const ecSignature = await signatureUtils.ecSignOrderHashAsync(
-                fakeProvider,
+            const ecSignature = await signatureUtils.ecSignHashAsync(fakeProvider, orderHash, makerAddress);
+            expect(ecSignature).to.equal(expectedSignature);
+        });
+        it('should return a valid signature', async () => {
+            const orderHash = '0x34decbedc118904df65f379a175bb39ca18209d6ce41d5ed549d54e6e0a95004';
+            const ecSignature = await signatureUtils.ecSignHashAsync(provider, orderHash, makerAddress);
+
+            const isValidSignature = await signatureUtils.isValidSignatureAsync(
+                provider,
                 orderHash,
+                ecSignature,
                 makerAddress,
-                SignerType.Default,
             );
-            expect(ecSignature).to.equal(expectedSignature);
+            expect(isValidSignature).to.be.true();
         });
-        // Note this is due to a bug in Metamask where it does not prefix before signing, this is a known issue and is to be fixed in the future
-        // Source: https://github.com/MetaMask/metamask-extension/commit/a9d36860bec424dcee8db043d3e7da6a5ff5672e
-        it('should receive a payload modified with a prefix when Metamask is SignerType', async () => {
-            const orderHash = '0x34decbedc118904df65f379a175bb39ca18209d6ce41d5ed549d54e6e0a95004';
-            const orderHashPrefixed = '0xae70f31d26096291aa681b26cb7574563956221d0b4213631e1ef9df675d4cba';
+    });
+    describe('#ecSignTypedDataOrderAsync', () => {
+        it('should result in the same signature as signing the order hash without an ethereum message prefix', async () => {
+            // Note: Since order hash is an EIP712 hash the result of a valid EIP712 signature
+            //       of order hash is the same as signing the order without the Ethereum Message prefix.
+            const orderHashHex = orderHashUtils.getOrderHashHex(order);
+            const sig = ethUtil.ecsign(
+                ethUtil.toBuffer(orderHashHex),
+                Buffer.from('F2F48EE19680706196E2E339E5DA3491186E0C4C5030670656B0E0164837257D', 'hex'),
+            );
+            const signatureBuffer = Buffer.concat([
+                ethUtil.toBuffer(sig.v),
+                ethUtil.toBuffer(sig.r),
+                ethUtil.toBuffer(sig.s),
+                ethUtil.toBuffer(SignatureType.EIP712),
+            ]);
+            const signatureHex = `0x${signatureBuffer.toString('hex')}`;
+            const signedOrder = await signatureUtils.ecSignTypedDataOrderAsync(provider, order, makerAddress);
+            const isValidSignature = await signatureUtils.isValidSignatureAsync(
+                provider,
+                orderHashHex,
+                signedOrder.signature,
+                makerAddress,
+            );
+            expect(signatureHex).to.eq(signedOrder.signature);
+            expect(isValidSignature).to.eq(true);
+        });
+        it('should return the correct Signature for signatureHex concatenated as R + S + V', async () => {
             const expectedSignature =
-                '0x1b117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d872871137feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b03';
-            // Generated from a MM eth_sign request from 0x5409ed021d9299bf6814279a6a1411a7e866a631 signing 0xae70f31d26096291aa681b26cb7574563956221d0b4213631e1ef9df675d4cba
-            const metamaskSignature =
-                '0x117902c86dfb95fe0d1badd983ee166ad259b27acb220174cbb4460d872871137feabdfe76e05924b484789f79af4ee7fa29ec006cedce1bbf369320d034e10b1b';
+                '0x1cd472c439833774b55d248c31b6585f21aea1b9363ebb4ec58549e46b62eb5a6f696f5781f62de008ee7f77650ef940d99c97ec1dee67b3f5cea1bbfdfeb2eba602';
             const fakeProvider = {
                 async sendAsync(payload: JSONRPCRequestPayload, callback: JSONRPCErrorCallback): Promise<void> {
-                    if (payload.method === 'eth_sign') {
-                        const [, message] = payload.params;
-                        expect(message).to.equal(orderHashPrefixed);
+                    if (payload.method === 'eth_signTypedData') {
+                        const [address, typedData] = payload.params;
+                        const signature = await web3Wrapper.signTypedDataAsync(address, typedData);
                         callback(null, {
                             id: 42,
                             jsonrpc: '2.0',
-                            result: metamaskSignature,
+                            result: signature,
                         });
                     } else {
                         callback(null, { id: 42, jsonrpc: '2.0', result: [makerAddress] });
                     }
                 },
             };
-
-            const ecSignature = await signatureUtils.ecSignOrderHashAsync(
-                fakeProvider,
-                orderHash,
-                makerAddress,
-                SignerType.Metamask,
-            );
-            expect(ecSignature).to.equal(expectedSignature);
-        });
-        it('should return a valid signature', async () => {
-            const orderHash = '0x34decbedc118904df65f379a175bb39ca18209d6ce41d5ed549d54e6e0a95004';
-            const ecSignature = await signatureUtils.ecSignOrderHashAsync(
-                provider,
-                orderHash,
-                makerAddress,
-                SignerType.Default,
-            );
-
-            const isValidSignature = await signatureUtils.isValidSignatureAsync(
-                provider,
-                orderHash,
-                ecSignature,
-                makerAddress,
-            );
-            expect(isValidSignature).to.be.true();
+            const signedOrder = await signatureUtils.ecSignTypedDataOrderAsync(fakeProvider, order, makerAddress);
+            expect(signedOrder.signature).to.equal(expectedSignature);
         });
     });
     describe('#convertECSignatureToSignatureHex', () => {
@@ -256,38 +314,11 @@ describe('Signature utils', () => {
             r: '0xaca7da997ad177f040240cdccf6905b71ab16b74434388c3a72f34fd25d64393',
             s: '0x46b2bac274ff29b48b3ea6e2d04c1336eaceafda3c53ab483fc3ff12fac3ebf2',
         };
-        it('should concatenate v,r,s and append the EthSign signature type when SignerType is Default', async () => {
+        it('should concatenate v,r,s and append the EthSign signature type', async () => {
             const expectedSignatureWithSignatureType =
                 '0x1baca7da997ad177f040240cdccf6905b71ab16b74434388c3a72f34fd25d6439346b2bac274ff29b48b3ea6e2d04c1336eaceafda3c53ab483fc3ff12fac3ebf203';
-            const signatureWithSignatureType = signatureUtils.convertECSignatureToSignatureHex(
-                ecSignature,
-                SignerType.Default,
-            );
+            const signatureWithSignatureType = signatureUtils.convertECSignatureToSignatureHex(ecSignature);
             expect(signatureWithSignatureType).to.equal(expectedSignatureWithSignatureType);
         });
-        it('should concatenate v,r,s and append the EthSign signature type when SignerType is Ledger', async () => {
-            const expectedSignatureWithSignatureType =
-                '0x1baca7da997ad177f040240cdccf6905b71ab16b74434388c3a72f34fd25d6439346b2bac274ff29b48b3ea6e2d04c1336eaceafda3c53ab483fc3ff12fac3ebf203';
-            const signatureWithSignatureType = signatureUtils.convertECSignatureToSignatureHex(
-                ecSignature,
-                SignerType.Ledger,
-            );
-            expect(signatureWithSignatureType).to.equal(expectedSignatureWithSignatureType);
-        });
-        it('should concatenate v,r,s and append the EthSign signature type when SignerType is Metamask', async () => {
-            const expectedSignatureWithSignatureType =
-                '0x1baca7da997ad177f040240cdccf6905b71ab16b74434388c3a72f34fd25d6439346b2bac274ff29b48b3ea6e2d04c1336eaceafda3c53ab483fc3ff12fac3ebf203';
-            const signatureWithSignatureType = signatureUtils.convertECSignatureToSignatureHex(
-                ecSignature,
-                SignerType.Metamask,
-            );
-            expect(signatureWithSignatureType).to.equal(expectedSignatureWithSignatureType);
-        });
-        it('should throw if the SignerType is invalid', async () => {
-            const expectedMessage = 'Unrecognized SignerType: INVALID_SIGNER';
-            expect(() =>
-                signatureUtils.convertECSignatureToSignatureHex(ecSignature, 'INVALID_SIGNER' as SignerType),
-            ).to.throw(expectedMessage);
-        });
     });
 });