Atomic Order Matching - Tests

10 files changed, 1412 insertions, 33 deletions

diff --git a/packages/contracts/src/utils/asset_proxy_utils.ts b/packages/contracts/src/utils/asset_proxy_utils.ts
index dc31c3497..9a26a9ca7 100644
--- a/packages/contracts/src/utils/asset_proxy_utils.ts
+++ b/packages/contracts/src/utils/asset_proxy_utils.ts
@@ -8,6 +8,9 @@ export const assetProxyUtils = {
     encodeAssetProxyId(assetProxyId: AssetProxyId): Buffer {
         return ethUtil.toBuffer(assetProxyId);
     },
+    decodeAssetProxyId(encodedAssetProxyId: Buffer): AssetProxyId {
+        return ethUtil.bufferToInt(encodedAssetProxyId);
+    },
     encodeAddress(address: string): Buffer {
         if (!ethUtil.isValidAddress(address)) {
             throw new Error(`Invalid Address: ${address}`);
@@ -15,12 +18,24 @@ export const assetProxyUtils = {
         const encodedAddress = ethUtil.toBuffer(address);
         return encodedAddress;
     },
+    decodeAddress(encodedAddress: Buffer): string {
+        const address = ethUtil.bufferToHex(encodedAddress);
+        if (!ethUtil.isValidAddress(address)) {
+            throw new Error(`Invalid Address: ${address}`);
+        }
+        return address;
+    },
     encodeUint256(value: BigNumber): Buffer {
         const formattedValue = new BN(value.toString(10));
         const encodedValue = ethUtil.toBuffer(formattedValue);
         const paddedValue = ethUtil.setLengthLeft(encodedValue, 32);
         return paddedValue;
     },
+    decodeUint256(encodedValue: Buffer): BigNumber {
+        const formattedValue = ethUtil.bufferToHex(encodedValue);
+        const value = new BigNumber(formattedValue, 16);
+        return value;
+    },
     encodeERC20ProxyData(tokenAddress: string): string {
         const encodedAssetProxyId = assetProxyUtils.encodeAssetProxyId(AssetProxyId.ERC20);
         const encodedAddress = assetProxyUtils.encodeAddress(tokenAddress);
@@ -28,6 +43,28 @@ export const assetProxyUtils = {
         const encodedMetadataHex = ethUtil.bufferToHex(encodedMetadata);
         return encodedMetadataHex;
     },
+    decodeERC20ProxyData(proxyData: string): string /* tokenAddress */ {
+        const encodedProxyMetadata = ethUtil.toBuffer(proxyData);
+        if (encodedProxyMetadata.byteLength !== 21) {
+            throw new Error(
+                `Could not decode ERC20 Proxy Data. Expected length of encoded data to be 21. Got ${
+                    encodedProxyMetadata.byteLength
+                }`,
+            );
+        }
+        const encodedAssetProxyId = encodedProxyMetadata.slice(0, 1);
+        const assetProxyId = assetProxyUtils.decodeAssetProxyId(encodedAssetProxyId);
+        if (assetProxyId !== AssetProxyId.ERC20) {
+            throw new Error(
+                `Could not decode ERC20 Proxy Data. Expected Asset Proxy Id to be ERC20 (${
+                    AssetProxyId.ERC20
+                }), but got ${assetProxyId}`,
+            );
+        }
+        const encodedTokenAddress = encodedProxyMetadata.slice(1, 21);
+        const tokenAddress = assetProxyUtils.decodeAddress(encodedTokenAddress);
+        return tokenAddress;
+    },
     encodeERC721ProxyData(tokenAddress: string, tokenId: BigNumber): string {
         const encodedAssetProxyId = assetProxyUtils.encodeAssetProxyId(AssetProxyId.ERC721);
         const encodedAddress = assetProxyUtils.encodeAddress(tokenAddress);
@@ -36,4 +73,41 @@ export const assetProxyUtils = {
         const encodedMetadataHex = ethUtil.bufferToHex(encodedMetadata);
         return encodedMetadataHex;
     },
+    decodeERC721ProxyData(proxyData: string): [string /* tokenAddress */, BigNumber /* tokenId */] {
+        const encodedProxyMetadata = ethUtil.toBuffer(proxyData);
+        if (encodedProxyMetadata.byteLength !== 53) {
+            throw new Error(
+                `Could not decode ERC20 Proxy Data. Expected length of encoded data to be 53. Got ${
+                    encodedProxyMetadata.byteLength
+                }`,
+            );
+        }
+        const encodedAssetProxyId = encodedProxyMetadata.slice(0, 1);
+        const assetProxyId = assetProxyUtils.decodeAssetProxyId(encodedAssetProxyId);
+        if (assetProxyId !== AssetProxyId.ERC721) {
+            throw new Error(
+                `Could not decode ERC721 Proxy Data. Expected Asset Proxy Id to be ERC721 (${
+                    AssetProxyId.ERC721
+                }), but got ${assetProxyId}`,
+            );
+        }
+        const encodedTokenAddress = encodedProxyMetadata.slice(1, 21);
+        const tokenAddress = assetProxyUtils.decodeAddress(encodedTokenAddress);
+        const encodedTokenId = encodedProxyMetadata.slice(21, 53);
+        const tokenId = assetProxyUtils.decodeUint256(encodedTokenId);
+        return [tokenAddress, tokenId];
+    },
+    decodeProxyDataId(proxyData: string): AssetProxyId {
+        const encodedProxyMetadata = ethUtil.toBuffer(proxyData);
+        if (encodedProxyMetadata.byteLength < 1) {
+            throw new Error(
+                `Could not decode Proxy Data. Expected length of encoded data to be at least 1. Got ${
+                    encodedProxyMetadata.byteLength
+                }`,
+            );
+        }
+        const encodedAssetProxyId = encodedProxyMetadata.slice(0, 1);
+        const assetProxyId = assetProxyUtils.decodeAssetProxyId(encodedAssetProxyId);
+        return assetProxyId;
+    },
 };
diff --git a/packages/contracts/src/utils/exchange_wrapper.ts b/packages/contracts/src/utils/exchange_wrapper.ts
index 27fdd698f..6d36198f2 100644
--- a/packages/contracts/src/utils/exchange_wrapper.ts
+++ b/packages/contracts/src/utils/exchange_wrapper.ts
@@ -231,4 +231,26 @@ export class ExchangeWrapper {
         tx.logs = _.map(tx.logs, log => this._logDecoder.decodeLogOrThrow(log));
         return tx;
     }
+    public async getOrderInfoAsync(
+        signedOrder: SignedOrder,
+    ): Promise<[number /* orderStatus */, string /* orderHash */, BigNumber /* orderTakerAssetAmountFilled */]> {
+        const orderInfo: [number, string, BigNumber] = await this._exchange.getOrderInfo.callAsync(signedOrder);
+        return orderInfo;
+    }
+    public async matchOrdersAsync(
+        signedOrderLeft: SignedOrder,
+        signedOrderRight: SignedOrder,
+        from: string,
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const params = orderUtils.createMatchOrders(signedOrderLeft, signedOrderRight);
+        const txHash = await this._exchange.matchOrders.sendTransactionAsync(
+            params.left,
+            params.right,
+            params.leftSignature,
+            params.rightSignature,
+            { from },
+        );
+        const tx = await this._getTxWithDecodedExchangeLogsAsync(txHash);
+        return tx;
+    }
 }
diff --git a/packages/contracts/src/utils/order_utils.ts b/packages/contracts/src/utils/order_utils.ts
index 10bbf4f7c..7a482ad9e 100644
--- a/packages/contracts/src/utils/order_utils.ts
+++ b/packages/contracts/src/utils/order_utils.ts
@@ -80,4 +80,13 @@ export const orderUtils = {
         const orderHashHex = `0x${orderHashBuff.toString('hex')}`;
         return orderHashHex;
     },
+    createMatchOrders(signedOrderLeft: SignedOrder, signedOrderRight: SignedOrder) {
+        const fill = {
+            left: orderUtils.getOrderStruct(signedOrderLeft),
+            right: orderUtils.getOrderStruct(signedOrderRight),
+            leftSignature: signedOrderLeft.signature,
+            rightSignature: signedOrderRight.signature,
+        };
+        return fill;
+    },
 };
diff --git a/packages/contracts/src/utils/types.ts b/packages/contracts/src/utils/types.ts
index 234b14ef9..ce7fbcbe1 100644
--- a/packages/contracts/src/utils/types.ts
+++ b/packages/contracts/src/utils/types.ts
@@ -74,12 +74,27 @@ export interface Token {
     swarmHash: string;
 }
 
-export enum ExchangeContractErrs {
-    ERROR_ORDER_EXPIRED,
-    ERROR_ORDER_FULLY_FILLED,
-    ERROR_ORDER_CANCELLED,
-    ERROR_ROUNDING_ERROR_TOO_LARGE,
-    ERROR_INSUFFICIENT_BALANCE_OR_ALLOWANCE,
+export enum ExchangeStatus {
+    /// Default Status ///
+    INVALID, // General invalid status
+
+    /// General Exchange Statuses ///
+    SUCCESS, // Indicates a successful operation
+    ROUNDING_ERROR_TOO_LARGE, // Rounding error too large
+    INSUFFICIENT_BALANCE_OR_ALLOWANCE, // Insufficient balance or allowance for token transfer
+    TAKER_ASSET_FILL_AMOUNT_TOO_LOW, // takerAssetFillAmount is <= 0
+    INVALID_SIGNATURE, // Invalid signature
+    INVALID_SENDER, // Invalid sender
+    INVALID_TAKER, // Invalid taker
+    INVALID_MAKER, // Invalid maker
+
+    /// Order State Statuses ///
+    ORDER_INVALID_MAKER_ASSET_AMOUNT, // Order does not have a valid maker asset amount
+    ORDER_INVALID_TAKER_ASSET_AMOUNT, // Order does not have a valid taker asset amount
+    ORDER_FILLABLE, // Order is fillable
+    ORDER_EXPIRED, // Order has already expired
+    ORDER_FULLY_FILLED, // Order is fully filled
+    ORDER_CANCELLED, // Order has been cancelled
 }
 
 export enum ContractName {
@@ -143,3 +158,24 @@ export interface SignedTransaction {
     data: string;
     signature: string;
 }
+
+export interface TransferAmountsByMatchOrders {
+    // Left Maker
+    amountBoughtByLeftMaker: BigNumber;
+    amountSoldByLeftMaker: BigNumber;
+    amountReceivedByLeftMaker: BigNumber;
+    feePaidByLeftMaker: BigNumber;
+    // Right Maker
+    amountBoughtByRightMaker: BigNumber;
+    amountSoldByRightMaker: BigNumber;
+    amountReceivedByRightMaker: BigNumber;
+    feePaidByRightMaker: BigNumber;
+    // Taker
+    amountReceivedByTaker: BigNumber;
+    feePaidByTakerLeft: BigNumber;
+    feePaidByTakerRight: BigNumber;
+    totalFeePaidByTaker: BigNumber;
+    // Fee Recipients
+    feeReceivedLeft: BigNumber;
+    feeReceivedRight: BigNumber;
+}
diff --git a/packages/contracts/test/exchange/core.ts b/packages/contracts/test/exchange/core.ts
index 6c190d4da..e9c51ea18 100644
--- a/packages/contracts/test/exchange/core.ts
+++ b/packages/contracts/test/exchange/core.ts
@@ -12,7 +12,7 @@ import { ERC721ProxyContract } from '../../src/contract_wrappers/generated/e_r_c
 import {
     CancelContractEventArgs,
     ExchangeContract,
-    ExchangeErrorContractEventArgs,
+    ExchangeStatusContractEventArgs,
     FillContractEventArgs,
 } from '../../src/contract_wrappers/generated/exchange';
 import { artifacts } from '../../src/utils/artifacts';
@@ -25,8 +25,8 @@ import { ERC721Wrapper } from '../../src/utils/erc721_wrapper';
 import { ExchangeWrapper } from '../../src/utils/exchange_wrapper';
 import { OrderFactory } from '../../src/utils/order_factory';
 import { orderUtils } from '../../src/utils/order_utils';
-import { AssetProxyId, ERC20BalancesByOwner, ExchangeContractErrs, SignedOrder } from '../../src/utils/types';
-import { provider, txDefaults, web3Wrapper } from '../../src/utils/web3_wrapper';
+import { AssetProxyId, ContractName, ERC20BalancesByOwner, ExchangeStatus, SignedOrder } from '../../src/utils/types';
+import { provider, txDefaults, web3Wrapper } from '../utils/web3_wrapper';
 
 chaiSetup.configure();
 const expect = chai.expect;
@@ -556,9 +556,9 @@ describe('Exchange core', () => {
 
             const res = await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress);
             expect(res.logs).to.have.length(1);
-            const log = res.logs[0] as LogWithDecodedArgs<ExchangeErrorContractEventArgs>;
-            const errCode = log.args.errorId;
-            expect(errCode).to.be.equal(ExchangeContractErrs.ERROR_ORDER_EXPIRED);
+            const log = res.logs[0] as LogWithDecodedArgs<ExchangeStatusContractEventArgs>;
+            const statusCode = log.args.statusId;
+            expect(statusCode).to.be.equal(ExchangeStatus.ORDER_EXPIRED);
         });
 
         it('should log an error event if no value is filled', async () => {
@@ -567,9 +567,9 @@ describe('Exchange core', () => {
 
             const res = await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress);
             expect(res.logs).to.have.length(1);
-            const log = res.logs[0] as LogWithDecodedArgs<ExchangeErrorContractEventArgs>;
-            const errCode = log.args.errorId;
-            expect(errCode).to.be.equal(ExchangeContractErrs.ERROR_ORDER_FULLY_FILLED);
+            const log = res.logs[0] as LogWithDecodedArgs<ExchangeStatusContractEventArgs>;
+            const statusCode = log.args.statusId;
+            expect(statusCode).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
         });
     });
 
@@ -635,9 +635,9 @@ describe('Exchange core', () => {
 
             const res = await exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress);
             expect(res.logs).to.have.length(1);
-            const log = res.logs[0] as LogWithDecodedArgs<ExchangeErrorContractEventArgs>;
-            const errCode = log.args.errorId;
-            expect(errCode).to.be.equal(ExchangeContractErrs.ERROR_ORDER_CANCELLED);
+            const log = res.logs[0] as LogWithDecodedArgs<ExchangeStatusContractEventArgs>;
+            const statusCode = log.args.statusId;
+            expect(statusCode).to.be.equal(ExchangeStatus.ORDER_CANCELLED);
         });
 
         it('should log error if order is expired', async () => {
@@ -647,9 +647,9 @@ describe('Exchange core', () => {
 
             const res = await exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress);
             expect(res.logs).to.have.length(1);
-            const log = res.logs[0] as LogWithDecodedArgs<ExchangeErrorContractEventArgs>;
-            const errCode = log.args.errorId;
-            expect(errCode).to.be.equal(ExchangeContractErrs.ERROR_ORDER_EXPIRED);
+            const log = res.logs[0] as LogWithDecodedArgs<ExchangeStatusContractEventArgs>;
+            const statusCode = log.args.statusId;
+            expect(statusCode).to.be.equal(ExchangeStatus.ORDER_EXPIRED);
         });
     });
 
diff --git a/packages/contracts/test/exchange/match_orders.ts b/packages/contracts/test/exchange/match_orders.ts
new file mode 100644
index 000000000..a114d92ac
--- /dev/null
+++ b/packages/contracts/test/exchange/match_orders.ts
@@ -0,0 +1,873 @@
+import { LogWithDecodedArgs, ZeroEx } from '0x.js';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
+import { BigNumber } from '@0xproject/utils';
+import * as chai from 'chai';
+import ethUtil = require('ethereumjs-util');
+import * as _ from 'lodash';
+
+import { DummyERC20TokenContract } from '../../src/contract_wrappers/generated/dummy_e_r_c20_token';
+import { DummyERC721TokenContract } from '../../src/contract_wrappers/generated/dummy_e_r_c721_token';
+import { ERC20ProxyContract } from '../../src/contract_wrappers/generated/e_r_c20_proxy';
+import { ERC721ProxyContract } from '../../src/contract_wrappers/generated/e_r_c721_proxy';
+import {
+    CancelContractEventArgs,
+    ExchangeContract,
+    ExchangeStatusContractEventArgs,
+    FillContractEventArgs,
+} from '../../src/contract_wrappers/generated/exchange';
+import { assetProxyUtils } from '../../src/utils/asset_proxy_utils';
+import { constants } from '../../src/utils/constants';
+import { crypto } from '../../src/utils/crypto';
+import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
+import { ERC721Wrapper } from '../../src/utils/erc721_wrapper';
+import { ExchangeWrapper } from '../../src/utils/exchange_wrapper';
+import { OrderFactory } from '../../src/utils/order_factory';
+import { orderUtils } from '../../src/utils/order_utils';
+import {
+    AssetProxyId,
+    ContractName,
+    ERC20BalancesByOwner,
+    ERC721TokenIdsByOwner,
+    ExchangeStatus,
+    SignedOrder,
+} from '../../src/utils/types';
+import { chaiSetup } from '../utils/chai_setup';
+import { deployer } from '../utils/deployer';
+import { provider, web3Wrapper } from '../utils/web3_wrapper';
+
+import { MatchOrderTester } from '../utils/match_order_tester';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
+
+describe('matchOrdersAndVerifyBalancesAsync', () => {
+    let makerAddressLeft: string;
+    let makerAddressRight: string;
+    let owner: string;
+    let takerAddress: string;
+    let feeRecipientAddressLeft: string;
+    let feeRecipientAddressRight: string;
+
+    let erc20TokenA: DummyERC20TokenContract;
+    let erc20TokenB: DummyERC20TokenContract;
+    let zrxToken: DummyERC20TokenContract;
+    let erc721Token: DummyERC721TokenContract;
+    let exchange: ExchangeContract;
+    let erc20Proxy: ERC20ProxyContract;
+    let erc721Proxy: ERC721ProxyContract;
+
+    let erc20BalancesByOwner: ERC20BalancesByOwner;
+    let erc721TokenIdsByOwner: ERC721TokenIdsByOwner;
+    let exchangeWrapper: ExchangeWrapper;
+    let erc20Wrapper: ERC20Wrapper;
+    let erc721Wrapper: ERC721Wrapper;
+    let orderFactoryLeft: OrderFactory;
+    let orderFactoryRight: OrderFactory;
+
+    let erc721LeftMakerAssetIds: BigNumber[];
+    let erc721RightMakerAssetIds: BigNumber[];
+    let erc721TakerAssetIds: BigNumber[];
+
+    let defaultERC20MakerAssetAddress: string;
+    let defaultERC20TakerAssetAddress: string;
+    let defaultERC721AssetAddress: string;
+
+    let matchOrderTester: MatchOrderTester;
+
+    let zeroEx: ZeroEx;
+
+    before(async () => {
+        // Create accounts
+        const accounts = await web3Wrapper.getAvailableAddressesAsync();
+        const usedAddresses = ([
+            owner,
+            makerAddressLeft,
+            makerAddressRight,
+            takerAddress,
+            feeRecipientAddressLeft,
+            feeRecipientAddressRight,
+        ] = accounts);
+        // Create wrappers
+        erc20Wrapper = new ERC20Wrapper(deployer, provider, usedAddresses, owner);
+        erc721Wrapper = new ERC721Wrapper(deployer, provider, usedAddresses, owner);
+        // Deploy ERC20 token & ERC20 proxy
+        [erc20TokenA, erc20TokenB, zrxToken] = await erc20Wrapper.deployDummyTokensAsync();
+        erc20Proxy = await erc20Wrapper.deployProxyAsync();
+        await erc20Wrapper.setBalancesAndAllowancesAsync();
+        // Deploy ERC721 token and proxy
+        [erc721Token] = await erc721Wrapper.deployDummyTokensAsync();
+        erc721Proxy = await erc721Wrapper.deployProxyAsync();
+        await erc721Wrapper.setBalancesAndAllowancesAsync();
+        const erc721Balances = await erc721Wrapper.getBalancesAsync();
+        erc721LeftMakerAssetIds = erc721Balances[makerAddressLeft][erc721Token.address];
+        erc721RightMakerAssetIds = erc721Balances[makerAddressRight][erc721Token.address];
+        erc721TakerAssetIds = erc721Balances[takerAddress][erc721Token.address];
+        // Depoy exchange
+        const exchangeInstance = await deployer.deployAsync(ContractName.Exchange, [
+            assetProxyUtils.encodeERC20ProxyData(zrxToken.address),
+        ]);
+        exchange = new ExchangeContract(exchangeInstance.abi, exchangeInstance.address, provider);
+        zeroEx = new ZeroEx(provider, {
+            exchangeContractAddress: exchange.address,
+            networkId: constants.TESTRPC_NETWORK_ID,
+        });
+        exchangeWrapper = new ExchangeWrapper(exchange, zeroEx);
+        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC20, erc20Proxy.address, owner);
+        await exchangeWrapper.registerAssetProxyAsync(AssetProxyId.ERC721, erc721Proxy.address, owner);
+        // Authorize ERC20 and ERC721 trades by exchange
+        await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
+            from: owner,
+        });
+        await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(exchange.address, {
+            from: owner,
+        });
+        // Set default addresses
+        defaultERC20MakerAssetAddress = erc20TokenA.address;
+        defaultERC20TakerAssetAddress = erc20TokenB.address;
+        defaultERC721AssetAddress = erc721Token.address;
+        // Create default order parameters
+        const defaultOrderParams = {
+            ...constants.STATIC_ORDER_PARAMS,
+            exchangeAddress: exchange.address,
+            makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+            takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+        };
+        const privateKeyLeft = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(makerAddressLeft)];
+        orderFactoryLeft = new OrderFactory(privateKeyLeft, defaultOrderParams);
+        const privateKeyRight = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(makerAddressRight)];
+        orderFactoryRight = new OrderFactory(privateKeyRight, defaultOrderParams);
+        // Set match order tester
+        matchOrderTester = new MatchOrderTester(exchangeWrapper, erc20Wrapper, erc721Wrapper);
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('matchOrders', () => {
+        beforeEach(async () => {
+            erc20BalancesByOwner = await erc20Wrapper.getBalancesAsync();
+            erc721TokenIdsByOwner = await erc721Wrapper.getBalancesAsync();
+        });
+
+        it('should transfer the correct amounts when orders completely fill each other', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match signedOrderLeft with signedOrderRight
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was fully filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify right order was fully filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+        });
+
+        it('should transfer the correct amounts when orders completely fill each other and taker doesnt take a profit', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Store original taker balance
+            const takerInitialBalances = _.cloneDeep(erc20BalancesByOwner[takerAddress][defaultERC20MakerAssetAddress]);
+            // Match signedOrderLeft with signedOrderRight
+            let newERC20BalancesByOwner: ERC20BalancesByOwner;
+            let newERC721TokenIdsByOwner: ERC721TokenIdsByOwner;
+            [
+                newERC20BalancesByOwner,
+                newERC721TokenIdsByOwner,
+            ] = await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was fully filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify right order was fully filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify taker did not take a profit
+            expect(takerInitialBalances).to.be.deep.equal(
+                newERC20BalancesByOwner[takerAddress][defaultERC20MakerAssetAddress],
+            );
+        });
+
+        it('should transfer the correct amounts when left order is completely filled and right order is partially filled', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(20), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(4), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was fully filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify right order was partially filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FILLABLE);
+        });
+
+        it('should transfer the correct amounts when right order is completely filled and left order is partially filled', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(50), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was partially filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FILLABLE);
+            // Verify right order was fully filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+        });
+
+        it('should transfer the correct amounts when consecutive calls are used to completely fill the left order', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(50), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            let newERC20BalancesByOwner: ERC20BalancesByOwner;
+            let newERC721TokenIdsByOwner: ERC721TokenIdsByOwner;
+            [
+                newERC20BalancesByOwner,
+                newERC721TokenIdsByOwner,
+            ] = await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was partially filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FILLABLE);
+            // Verify right order was fully filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Construct second right order
+            // Note: This order needs makerAssetAmount=90/takerAssetAmount=[anything <= 45] to fully fill the right order.
+            //       However, we use 100/50 to ensure a partial fill as we want to go down the "left fill"
+            //       branch in the contract twice for this test.
+            const signedOrderRight2 = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(50), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match signedOrderLeft with signedOrderRight2
+            const leftTakerAssetFilledAmount = signedOrderRight.makerAssetAmount;
+            const rightTakerAssetFilledAmount = new BigNumber(0);
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight2,
+                zrxToken.address,
+                takerAddress,
+                newERC20BalancesByOwner,
+                erc721TokenIdsByOwner,
+                leftTakerAssetFilledAmount,
+                rightTakerAssetFilledAmount,
+            );
+            // Verify left order was fully filled
+            const leftOrderInfo2: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderLeft,
+            );
+            expect(leftOrderInfo2[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify second right order was partially filled
+            const rightOrderInfo2: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight2,
+            );
+            expect(rightOrderInfo2[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FILLABLE);
+        });
+
+        it('should transfer the correct amounts when consecutive calls are used to completely fill the right order', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(50), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            let newERC20BalancesByOwner: ERC20BalancesByOwner;
+            let newERC721TokenIdsByOwner: ERC721TokenIdsByOwner;
+            [
+                newERC20BalancesByOwner,
+                newERC721TokenIdsByOwner,
+            ] = await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was partially filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify right order was fully filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FILLABLE);
+            // Create second left order
+            // Note: This order needs makerAssetAmount=96/takerAssetAmount=48 to fully fill the right order.
+            //       However, we use 100/50 to ensure a partial fill as we want to go down the "right fill"
+            //       branch in the contract twice for this test.
+            const signedOrderLeft2 = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(50), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            // Match signedOrderLeft2 with signedOrderRight
+            const leftTakerAssetFilledAmount = new BigNumber(0);
+            const takerAmountReceived = newERC20BalancesByOwner[takerAddress][defaultERC20MakerAssetAddress].minus(
+                erc20BalancesByOwner[takerAddress][defaultERC20MakerAssetAddress],
+            );
+            const rightTakerAssetFilledAmount = signedOrderLeft.makerAssetAmount.minus(takerAmountReceived);
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft2,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                newERC20BalancesByOwner,
+                erc721TokenIdsByOwner,
+                leftTakerAssetFilledAmount,
+                rightTakerAssetFilledAmount,
+            );
+            // Verify second left order was partially filled
+            const leftOrderInfo2: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderLeft2,
+            );
+            expect(leftOrderInfo2[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FILLABLE);
+            // Verify right order was fully filled
+            const rightOrderInfo2: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo2[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+        });
+
+        it('should transfer the correct amounts if fee recipient is the same across both matched orders', async () => {
+            const feeRecipientAddress = feeRecipientAddressLeft;
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress,
+            });
+            // Match orders
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+        });
+
+        it('should transfer the correct amounts if taker is also the left order maker', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            takerAddress = signedOrderLeft.makerAddress;
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+        });
+
+        it('should transfer the correct amounts if taker is also the right order maker', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            takerAddress = signedOrderRight.makerAddress;
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+        });
+
+        it('should transfer the correct amounts if taker is also the left fee recipient', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            takerAddress = feeRecipientAddressLeft;
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+        });
+
+        it('should transfer the correct amounts if taker is also the right fee recipient', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            takerAddress = feeRecipientAddressRight;
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+        });
+
+        it('should transfer the correct amounts if left maker is the left fee recipient and right maker is the right fee recipient', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: makerAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: makerAddressRight,
+            });
+            // Match orders
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+        });
+
+        it('Should not transfer any amounts if left order is not fillable', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Cancel left order
+            await exchangeWrapper.cancelOrderAsync(signedOrderLeft, signedOrderLeft.makerAddress);
+            // Match orders
+            await exchangeWrapper.matchOrdersAsync(signedOrderLeft, signedOrderRight, takerAddress);
+            // Verify balances did not change
+            const newBalances = await erc20Wrapper.getBalancesAsync();
+            expect(newBalances).to.be.deep.equal(erc20BalancesByOwner);
+        });
+
+        it('Should not transfer any amounts if right order is not fillable', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Cancel right order
+            await exchangeWrapper.cancelOrderAsync(signedOrderRight, signedOrderRight.makerAddress);
+            // Match orders
+            await exchangeWrapper.matchOrdersAsync(signedOrderLeft, signedOrderRight, takerAddress);
+            // Verify balances did not change
+            const newBalances = await erc20Wrapper.getBalancesAsync();
+            expect(newBalances).to.be.deep.equal(erc20BalancesByOwner);
+        });
+
+        it('should throw if there is not a positive spread', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(100), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(1), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(200), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            return expect(
+                matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                    signedOrderLeft,
+                    signedOrderRight,
+                    zrxToken.address,
+                    takerAddress,
+                    erc20BalancesByOwner,
+                    erc721TokenIdsByOwner,
+                ),
+            ).to.be.rejectedWith(constants.REVERT);
+        });
+
+        it('should throw if the left maker asset is not equal to the right taker asset ', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            return expect(
+                matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                    signedOrderLeft,
+                    signedOrderRight,
+                    zrxToken.address,
+                    takerAddress,
+                    erc20BalancesByOwner,
+                    erc721TokenIdsByOwner,
+                ),
+            ).to.be.rejectedWith(constants.REVERT);
+        });
+
+        it('should throw if the right maker asset is not equal to the left taker asset', async () => {
+            // Create orders to match
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(5), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(2), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            return expect(
+                matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                    signedOrderLeft,
+                    signedOrderRight,
+                    zrxToken.address,
+                    takerAddress,
+                    erc20BalancesByOwner,
+                    erc721TokenIdsByOwner,
+                ),
+            ).to.be.rejectedWith(constants.REVERT);
+        });
+
+        it('should transfer correct amounts when left order maker asset is an ERC721 token', async () => {
+            // Create orders to match
+            const erc721TokenToTransfer = erc721LeftMakerAssetIds[0];
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC721ProxyData(defaultERC721AssetAddress, erc721TokenToTransfer),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                makerAssetAmount: new BigNumber(1),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20TakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC721ProxyData(defaultERC721AssetAddress, erc721TokenToTransfer),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: new BigNumber(1),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was fully filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify right order was fully filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+        });
+
+        it('should transfer correct amounts when right order maker asset is an ERC721 token', async () => {
+            // Create orders to match
+            const erc721TokenToTransfer = erc721RightMakerAssetIds[0];
+            const signedOrderLeft = orderFactoryLeft.newSignedOrder({
+                makerAddress: makerAddressLeft,
+                makerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                takerAssetData: assetProxyUtils.encodeERC721ProxyData(defaultERC721AssetAddress, erc721TokenToTransfer),
+                makerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                takerAssetAmount: new BigNumber(1),
+                feeRecipientAddress: feeRecipientAddressLeft,
+            });
+            const signedOrderRight = orderFactoryRight.newSignedOrder({
+                makerAddress: makerAddressRight,
+                makerAssetData: assetProxyUtils.encodeERC721ProxyData(defaultERC721AssetAddress, erc721TokenToTransfer),
+                takerAssetData: assetProxyUtils.encodeERC20ProxyData(defaultERC20MakerAssetAddress),
+                makerAssetAmount: new BigNumber(1),
+                takerAssetAmount: ZeroEx.toBaseUnitAmount(new BigNumber(10), 18),
+                feeRecipientAddress: feeRecipientAddressRight,
+            });
+            // Match orders
+            await matchOrderTester.matchOrdersAndVerifyBalancesAsync(
+                signedOrderLeft,
+                signedOrderRight,
+                zrxToken.address,
+                takerAddress,
+                erc20BalancesByOwner,
+                erc721TokenIdsByOwner,
+            );
+            // Verify left order was fully filled
+            const leftOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(signedOrderLeft);
+            expect(leftOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+            // Verify right order was fully filled
+            const rightOrderInfo: [number, string, BigNumber] = await exchangeWrapper.getOrderInfoAsync(
+                signedOrderRight,
+            );
+            expect(rightOrderInfo[0] as ExchangeStatus).to.be.equal(ExchangeStatus.ORDER_FULLY_FILLED);
+        });
+    });
+}); // tslint:disable-line:max-file-line-count
diff --git a/packages/contracts/test/exchange/transactions.ts b/packages/contracts/test/exchange/transactions.ts
index a71b50a61..482475554 100644
--- a/packages/contracts/test/exchange/transactions.ts
+++ b/packages/contracts/test/exchange/transactions.ts
@@ -21,7 +21,7 @@ import { TransactionFactory } from '../../src/utils/transaction_factory';
 import {
     AssetProxyId,
     ERC20BalancesByOwner,
-    ExchangeContractErrs,
+    ExchangeStatus,
     OrderStruct,
     SignatureType,
     SignedOrder,
@@ -197,7 +197,7 @@ describe('Exchange transactions', () => {
 
             it('should cancel the order when signed by maker and called by sender', async () => {
                 await exchangeWrapper.executeTransactionAsync(signedTx, senderAddress);
-                const res = await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress);
+                const res = await exchangeWrapper.fillOrderAsync(signedOrder, senderAddress);
                 const newBalances = await erc20Wrapper.getBalancesAsync();
                 expect(newBalances).to.deep.equal(erc20Balances);
             });
diff --git a/packages/contracts/test/utils/match_order_tester.ts b/packages/contracts/test/utils/match_order_tester.ts
new file mode 100644
index 000000000..91c2ab0a3
--- /dev/null
+++ b/packages/contracts/test/utils/match_order_tester.ts
@@ -0,0 +1,353 @@
+import { LogWithDecodedArgs, ZeroEx } from '0x.js';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
+import { BigNumber } from '@0xproject/utils';
+import * as chai from 'chai';
+import ethUtil = require('ethereumjs-util');
+import * as _ from 'lodash';
+
+import { DummyERC20TokenContract } from '../../src/contract_wrappers/generated/dummy_e_r_c20_token';
+import { DummyERC721TokenContract } from '../../src/contract_wrappers/generated/dummy_e_r_c721_token';
+import { ERC20ProxyContract } from '../../src/contract_wrappers/generated/e_r_c20_proxy';
+import { ERC721ProxyContract } from '../../src/contract_wrappers/generated/e_r_c721_proxy';
+import {
+    CancelContractEventArgs,
+    ExchangeContract,
+    FillContractEventArgs,
+} from '../../src/contract_wrappers/generated/exchange';
+import { assetProxyUtils } from '../../src/utils/asset_proxy_utils';
+import { constants } from '../../src/utils/constants';
+import { crypto } from '../../src/utils/crypto';
+import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
+import { ERC721Wrapper } from '../../src/utils/erc721_wrapper';
+import { ExchangeWrapper } from '../../src/utils/exchange_wrapper';
+import { OrderFactory } from '../../src/utils/order_factory';
+import { orderUtils } from '../../src/utils/order_utils';
+import {
+    AssetProxyId,
+    ContractName,
+    ERC20BalancesByOwner,
+    ERC721TokenIdsByOwner,
+    ExchangeStatus,
+    SignedOrder,
+    TransferAmountsByMatchOrders as TransferAmounts,
+} from '../../src/utils/types';
+import { chaiSetup } from '../utils/chai_setup';
+import { deployer } from '../utils/deployer';
+import { provider, web3Wrapper } from '../utils/web3_wrapper';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
+
+export class MatchOrderTester {
+    private _exchangeWrapper: ExchangeWrapper;
+    private _erc20Wrapper: ERC20Wrapper;
+    private _erc721Wrapper: ERC721Wrapper;
+
+    /// @dev Calculates the expected balances of order makers, fee recipients, and the taker,
+    ///      as a result of matching two orders.
+    /// @param signedOrderLeft First matched order.
+    /// @param signedOrderRight Second matched order.
+    /// @param feeTokenAddress Address of ERC20 fee token.
+    /// @param takerAddress Address of taker (the address who matched the two orders)
+    /// @param erc20BalancesByOwner Current ERC20 balances.
+    /// @param erc721TokenIdsByOwner Current ERC721 token owners.
+    /// @param expectedTransferAmounts A struct containing the expected transfer amounts.
+    /// @return Expected ERC20 balances & ERC721 token owners after orders have been matched.
+    private static _calculateExpectedBalances(
+        signedOrderLeft: SignedOrder,
+        signedOrderRight: SignedOrder,
+        feeTokenAddress: string,
+        takerAddress: string,
+        erc20BalancesByOwner: ERC20BalancesByOwner,
+        erc721TokenIdsByOwner: ERC721TokenIdsByOwner,
+        expectedTransferAmounts: TransferAmounts,
+    ): [ERC20BalancesByOwner, ERC721TokenIdsByOwner] {
+        const makerAddressLeft = signedOrderLeft.makerAddress;
+        const makerAddressRight = signedOrderRight.makerAddress;
+        const feeRecipientAddressLeft = signedOrderLeft.feeRecipientAddress;
+        const feeRecipientAddressRight = signedOrderRight.feeRecipientAddress;
+        // Operations are performed on copies of the balances
+        const expectedNewERC20BalancesByOwner = _.cloneDeep(erc20BalancesByOwner);
+        const expectedNewERC721TokenIdsByOwner = _.cloneDeep(erc721TokenIdsByOwner);
+        // Left Maker Asset (Right Taker Asset)
+        const makerAssetProxyIdLeft = assetProxyUtils.decodeProxyDataId(signedOrderLeft.makerAssetData);
+        if (makerAssetProxyIdLeft === AssetProxyId.ERC20) {
+            // Decode asset data
+            const makerAssetAddressLeft = assetProxyUtils.decodeERC20ProxyData(signedOrderLeft.makerAssetData);
+            const takerAssetAddressRight = makerAssetAddressLeft;
+            // Left Maker
+            expectedNewERC20BalancesByOwner[makerAddressLeft][makerAssetAddressLeft] = expectedNewERC20BalancesByOwner[
+                makerAddressLeft
+            ][makerAssetAddressLeft].minus(expectedTransferAmounts.amountSoldByLeftMaker);
+            // Right Maker
+            expectedNewERC20BalancesByOwner[makerAddressRight][
+                takerAssetAddressRight
+            ] = expectedNewERC20BalancesByOwner[makerAddressRight][takerAssetAddressRight].add(
+                expectedTransferAmounts.amountReceivedByRightMaker,
+            );
+            // Taker
+            expectedNewERC20BalancesByOwner[takerAddress][makerAssetAddressLeft] = expectedNewERC20BalancesByOwner[
+                takerAddress
+            ][makerAssetAddressLeft].add(expectedTransferAmounts.amountReceivedByTaker);
+        } else if (makerAssetProxyIdLeft === AssetProxyId.ERC721) {
+            // Decode asset data
+            let makerAssetAddressLeft;
+            let makerAssetIdLeft;
+            [makerAssetAddressLeft, makerAssetIdLeft] = assetProxyUtils.decodeERC721ProxyData(
+                signedOrderLeft.makerAssetData,
+            );
+            const takerAssetAddressRight = makerAssetAddressLeft;
+            const takerAssetIdRight = makerAssetIdLeft;
+            // Left Maker
+            _.remove(expectedNewERC721TokenIdsByOwner[makerAddressLeft][makerAssetAddressLeft], makerAssetIdLeft);
+            // Right Maker
+            expectedNewERC721TokenIdsByOwner[makerAddressRight][takerAssetAddressRight].push(takerAssetIdRight);
+            // Taker: Since there is only 1 asset transferred, the taker does not receive any of the left maker asset.
+        }
+        // Left Taker Asset (Right Maker Asset)
+        // Note: This exchange is only between the order makers: the Taker does not receive any of the left taker asset.
+        const takerAssetProxyIdLeft = assetProxyUtils.decodeProxyDataId(signedOrderLeft.takerAssetData);
+        if (takerAssetProxyIdLeft === AssetProxyId.ERC20) {
+            // Decode asset data
+            const takerAssetAddressLeft = assetProxyUtils.decodeERC20ProxyData(signedOrderLeft.takerAssetData);
+            const makerAssetAddressRight = takerAssetAddressLeft;
+            // Left Maker
+            expectedNewERC20BalancesByOwner[makerAddressLeft][takerAssetAddressLeft] = expectedNewERC20BalancesByOwner[
+                makerAddressLeft
+            ][takerAssetAddressLeft].add(expectedTransferAmounts.amountReceivedByLeftMaker);
+            // Right Maker
+            expectedNewERC20BalancesByOwner[makerAddressRight][
+                makerAssetAddressRight
+            ] = expectedNewERC20BalancesByOwner[makerAddressRight][makerAssetAddressRight].minus(
+                expectedTransferAmounts.amountSoldByRightMaker,
+            );
+        } else if (takerAssetProxyIdLeft === AssetProxyId.ERC721) {
+            // Decode asset data
+            let makerAssetAddressRight;
+            let makerAssetIdRight;
+            [makerAssetAddressRight, makerAssetIdRight] = assetProxyUtils.decodeERC721ProxyData(
+                signedOrderRight.makerAssetData,
+            );
+            const takerAssetAddressLeft = makerAssetAddressRight;
+            const takerAssetIdLeft = makerAssetIdRight;
+            // Right Maker
+            _.remove(expectedNewERC721TokenIdsByOwner[makerAddressRight][makerAssetAddressRight], makerAssetIdRight);
+            // Left Maker
+            expectedNewERC721TokenIdsByOwner[makerAddressLeft][takerAssetAddressLeft].push(takerAssetIdLeft);
+        }
+        // Left Maker Fees
+        expectedNewERC20BalancesByOwner[makerAddressLeft][feeTokenAddress] = expectedNewERC20BalancesByOwner[
+            makerAddressLeft
+        ][feeTokenAddress].minus(expectedTransferAmounts.feePaidByLeftMaker);
+        // Right Maker Fees
+        expectedNewERC20BalancesByOwner[makerAddressRight][feeTokenAddress] = expectedNewERC20BalancesByOwner[
+            makerAddressRight
+        ][feeTokenAddress].minus(expectedTransferAmounts.feePaidByRightMaker);
+        // Taker Fees
+        expectedNewERC20BalancesByOwner[takerAddress][feeTokenAddress] = expectedNewERC20BalancesByOwner[takerAddress][
+            feeTokenAddress
+        ].minus(expectedTransferAmounts.totalFeePaidByTaker);
+        // Left Fee Recipient Fees
+        expectedNewERC20BalancesByOwner[feeRecipientAddressLeft][feeTokenAddress] = expectedNewERC20BalancesByOwner[
+            feeRecipientAddressLeft
+        ][feeTokenAddress].add(expectedTransferAmounts.feeReceivedLeft);
+        // Right Fee Recipient Fees
+        expectedNewERC20BalancesByOwner[feeRecipientAddressRight][feeTokenAddress] = expectedNewERC20BalancesByOwner[
+            feeRecipientAddressRight
+        ][feeTokenAddress].add(expectedTransferAmounts.feeReceivedRight);
+
+        return [expectedNewERC20BalancesByOwner, expectedNewERC721TokenIdsByOwner];
+    }
+
+    /// @dev Compares a pair of ERC20 balances and a pair of ERC721 token owners.
+    /// @param expectedNewERC20BalancesByOwner Expected ERC20 balances.
+    /// @param realERC20BalancesByOwner Actual ERC20 balances.
+    /// @param expectedNewERC721TokenIdsByOwner Expected ERC721 token owners.
+    /// @param realERC721TokenIdsByOwner Actual ERC20 token owners.
+    /// @return True only if ERC20 balances match and ERC721 token owners match.
+    private static _compareExpectedAndRealBalances(
+        expectedNewERC20BalancesByOwner: ERC20BalancesByOwner,
+        realERC20BalancesByOwner: ERC20BalancesByOwner,
+        expectedNewERC721TokenIdsByOwner: ERC721TokenIdsByOwner,
+        realERC721TokenIdsByOwner: ERC721TokenIdsByOwner,
+    ) {
+        // ERC20 Balances
+        const erc20BalancesMatch = _.isEqual(expectedNewERC20BalancesByOwner, realERC20BalancesByOwner);
+        if (!erc20BalancesMatch) {
+            return false;
+        }
+        // ERC721 Token Ids
+        const sortedExpectedNewERC721TokenIdsByOwner = _.mapValues(
+            expectedNewERC721TokenIdsByOwner,
+            tokenIdsByOwner => {
+                _.mapValues(tokenIdsByOwner, tokenIds => {
+                    _.sortBy(tokenIds);
+                });
+            },
+        );
+        const sortedNewERC721TokenIdsByOwner = _.mapValues(realERC721TokenIdsByOwner, tokenIdsByOwner => {
+            _.mapValues(tokenIdsByOwner, tokenIds => {
+                _.sortBy(tokenIds);
+            });
+        });
+        const erc721TokenIdsMatch = _.isEqual(sortedExpectedNewERC721TokenIdsByOwner, sortedNewERC721TokenIdsByOwner);
+        return erc721TokenIdsMatch;
+    }
+
+    /// @dev Constructs new MatchOrderTester.
+    /// @param exchangeWrapper Used to call to the Exchange.
+    /// @param erc20Wrapper Used to fetch ERC20 balances.
+    /// @param erc721Wrapper Used to fetch ERC721 token owners.
+    constructor(exchangeWrapper: ExchangeWrapper, erc20Wrapper: ERC20Wrapper, erc721Wrapper: ERC721Wrapper) {
+        this._exchangeWrapper = exchangeWrapper;
+        this._erc20Wrapper = erc20Wrapper;
+        this._erc721Wrapper = erc721Wrapper;
+    }
+
+    /// @dev Matches two complementary orders and validates results.
+    ///      Validation either succeeds or throws.
+    /// @param signedOrderLeft First matched order.
+    /// @param signedOrderRight Second matched order.
+    /// @param feeTokenAddress Address of ERC20 fee token.
+    /// @param takerAddress Address of taker (the address who matched the two orders)
+    /// @param erc20BalancesByOwner Current ERC20 balances.
+    /// @param erc721TokenIdsByOwner Current ERC721 token owners.
+    /// @param initialTakerAssetFilledAmountLeft Current amount the left order has been filled.
+    /// @param initialTakerAssetFilledAmountRight Current amount the right order has been filled.
+    /// @return New ERC20 balances & ERC721 token owners.
+    public async matchOrdersAndVerifyBalancesAsync(
+        signedOrderLeft: SignedOrder,
+        signedOrderRight: SignedOrder,
+        feeTokenAddress: string,
+        takerAddress: string,
+        erc20BalancesByOwner: ERC20BalancesByOwner,
+        erc721TokenIdsByOwner: ERC721TokenIdsByOwner,
+        initialTakerAssetFilledAmountLeft?: BigNumber,
+        initialTakerAssetFilledAmountRight?: BigNumber,
+    ): Promise<[ERC20BalancesByOwner, ERC721TokenIdsByOwner]> {
+        // Test setup & verify preconditions
+        const makerAddressLeft = signedOrderLeft.makerAddress;
+        const makerAddressRight = signedOrderRight.makerAddress;
+        const feeRecipientAddressLeft = signedOrderLeft.feeRecipientAddress;
+        const feeRecipientAddressRight = signedOrderRight.feeRecipientAddress;
+        // Verify Left order preconditions
+        const takerAssetFilledAmountBeforeLeft = await this._exchangeWrapper.getTakerAssetFilledAmountAsync(
+            orderUtils.getOrderHashHex(signedOrderLeft),
+        );
+        const expectedLeftOrderFillAmoutBeforeMatch = initialTakerAssetFilledAmountLeft
+            ? initialTakerAssetFilledAmountLeft
+            : new BigNumber(0);
+        expect(takerAssetFilledAmountBeforeLeft).to.be.bignumber.equal(expectedLeftOrderFillAmoutBeforeMatch);
+        // Verify Right order preconditions
+        const takerAssetFilledAmountBeforeRight = await this._exchangeWrapper.getTakerAssetFilledAmountAsync(
+            orderUtils.getOrderHashHex(signedOrderRight),
+        );
+        const expectedRightOrderFillAmoutBeforeMatch = initialTakerAssetFilledAmountRight
+            ? initialTakerAssetFilledAmountRight
+            : new BigNumber(0);
+        expect(takerAssetFilledAmountBeforeRight).to.be.bignumber.equal(expectedRightOrderFillAmoutBeforeMatch);
+        // Match left & right orders
+        await this._exchangeWrapper.matchOrdersAsync(signedOrderLeft, signedOrderRight, takerAddress);
+        const newERC20BalancesByOwner = await this._erc20Wrapper.getBalancesAsync();
+        const newERC721TokenIdsByOwner = await this._erc721Wrapper.getBalancesAsync();
+        // Calculate expected balance changes
+        const expectedTransferAmounts = await this._calculateExpectedTransferAmountsAsync(
+            signedOrderLeft,
+            signedOrderRight,
+            expectedLeftOrderFillAmoutBeforeMatch,
+            expectedRightOrderFillAmoutBeforeMatch,
+        );
+        let expectedERC20BalancesByOwner: ERC20BalancesByOwner;
+        let expectedERC721TokenIdsByOwner: ERC721TokenIdsByOwner;
+        [expectedERC20BalancesByOwner, expectedERC721TokenIdsByOwner] = MatchOrderTester._calculateExpectedBalances(
+            signedOrderLeft,
+            signedOrderRight,
+            feeTokenAddress,
+            takerAddress,
+            erc20BalancesByOwner,
+            erc721TokenIdsByOwner,
+            expectedTransferAmounts,
+        );
+        // Assert our expected balances are equal to the actual balances
+        const expectedBalancesMatchRealBalances = MatchOrderTester._compareExpectedAndRealBalances(
+            expectedERC20BalancesByOwner,
+            newERC20BalancesByOwner,
+            expectedERC721TokenIdsByOwner,
+            newERC721TokenIdsByOwner,
+        );
+        expect(expectedBalancesMatchRealBalances).to.be.true();
+        return [newERC20BalancesByOwner, newERC721TokenIdsByOwner];
+    }
+
+    /// @dev Calculates expected transfer amounts between order makers, fee recipients, and
+    ///      the taker when two orders are matched.
+    /// @param signedOrderLeft First matched order.
+    /// @param signedOrderRight Second matched order.
+    /// @param expectedLeftOrderFillAmoutBeforeMatch How much we expect the left order has been filled, prior to matching orders.
+    /// @param expectedRightOrderFillAmoutBeforeMatch How much we expect the right order has been filled, prior to matching orders.
+    /// @return TransferAmounts A struct containing the expected transfer amounts.
+    private async _calculateExpectedTransferAmountsAsync(
+        signedOrderLeft: SignedOrder,
+        signedOrderRight: SignedOrder,
+        expectedLeftOrderFillAmoutBeforeMatch: BigNumber,
+        expectedRightOrderFillAmoutBeforeMatch: BigNumber,
+    ): Promise<TransferAmounts> {
+        let amountBoughtByLeftMaker = await this._exchangeWrapper.getTakerAssetFilledAmountAsync(
+            orderUtils.getOrderHashHex(signedOrderLeft),
+        );
+        amountBoughtByLeftMaker = amountBoughtByLeftMaker.minus(expectedLeftOrderFillAmoutBeforeMatch);
+        const amountSoldByLeftMaker = amountBoughtByLeftMaker
+            .times(signedOrderLeft.makerAssetAmount)
+            .dividedToIntegerBy(signedOrderLeft.takerAssetAmount);
+        const amountReceivedByRightMaker = amountBoughtByLeftMaker
+            .times(signedOrderRight.takerAssetAmount)
+            .dividedToIntegerBy(signedOrderRight.makerAssetAmount);
+        const amountReceivedByTaker = amountSoldByLeftMaker.minus(amountReceivedByRightMaker);
+        let amountBoughtByRightMaker = await this._exchangeWrapper.getTakerAssetFilledAmountAsync(
+            orderUtils.getOrderHashHex(signedOrderRight),
+        );
+        amountBoughtByRightMaker = amountBoughtByRightMaker.minus(expectedRightOrderFillAmoutBeforeMatch);
+        const amountSoldByRightMaker = amountBoughtByRightMaker
+            .times(signedOrderRight.makerAssetAmount)
+            .dividedToIntegerBy(signedOrderRight.takerAssetAmount);
+        const amountReceivedByLeftMaker = amountSoldByRightMaker;
+        const feePaidByLeftMaker = signedOrderLeft.makerFee
+            .times(amountSoldByLeftMaker)
+            .dividedToIntegerBy(signedOrderLeft.makerAssetAmount);
+        const feePaidByRightMaker = signedOrderRight.makerFee
+            .times(amountSoldByRightMaker)
+            .dividedToIntegerBy(signedOrderRight.makerAssetAmount);
+        const feePaidByTakerLeft = signedOrderLeft.takerFee
+            .times(amountSoldByLeftMaker)
+            .dividedToIntegerBy(signedOrderLeft.makerAssetAmount);
+        const feePaidByTakerRight = signedOrderRight.takerFee
+            .times(amountSoldByRightMaker)
+            .dividedToIntegerBy(signedOrderRight.makerAssetAmount);
+        const totalFeePaidByTaker = feePaidByTakerLeft.add(feePaidByTakerRight);
+        const feeReceivedLeft = feePaidByLeftMaker.add(feePaidByTakerLeft);
+        const feeReceivedRight = feePaidByRightMaker.add(feePaidByTakerRight);
+        // Return values
+        const expectedTransferAmounts = {
+            // Left Maker
+            amountBoughtByLeftMaker,
+            amountSoldByLeftMaker,
+            amountReceivedByLeftMaker,
+            feePaidByLeftMaker,
+            // Right Maker
+            amountBoughtByRightMaker,
+            amountSoldByRightMaker,
+            amountReceivedByRightMaker,
+            feePaidByRightMaker,
+            // Taker
+            amountReceivedByTaker,
+            feePaidByTakerLeft,
+            feePaidByTakerRight,
+            totalFeePaidByTaker,
+            // Fee Recipients
+            feeReceivedLeft,
+            feeReceivedRight,
+        };
+        return expectedTransferAmounts;
+    }
+}
diff --git a/packages/metacoin/test/utils/chai_setup.ts b/packages/metacoin/test/utils/chai_setup.ts
index 1a8733093..49259a368 100644
--- a/packages/metacoin/test/utils/chai_setup.ts
+++ b/packages/metacoin/test/utils/chai_setup.ts
@@ -1,3 +1,4 @@
+import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
 import chaiAsPromised = require('chai-as-promised');
 import ChaiBigNumber = require('chai-bignumber');
@@ -9,5 +10,12 @@ export const chaiSetup = {
         chai.use(ChaiBigNumber());
         chai.use(dirtyChai);
         chai.use(chaiAsPromised);
+
+        // Node uses '.inspect()' instead of '.toString()' for log messages
+        // HACK: Typescript won't allow me to mess with BigNumber.prototype
+        // directly, so I create an instance and then get the prototype.
+        Object.getPrototypeOf(new BigNumber(0)).inspect = function() {
+            return this.toString();
+        };
     },
 };
diff --git a/yarn.lock b/yarn.lock
index d0b1276d9..718717580 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1879,10 +1879,6 @@ buffer-from@^0.1.1:
   version "0.1.2"
   resolved "https://registry.yarnpkg.com/buffer-from/-/buffer-from-0.1.2.tgz#15f4b9bcef012044df31142c14333caf6e0260d0"
 
-buffer-from@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/buffer-from/-/buffer-from-1.0.0.tgz#4cb8832d23612589b0406e9e2956c17f06fdf531"
-
 buffer-indexof@^1.0.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/buffer-indexof/-/buffer-indexof-1.1.1.tgz#52fabcc6a606d1a00302802648ef68f639da268c"
@@ -2513,7 +2509,15 @@ concat-map@0.0.1:
   version "0.0.1"
   resolved "https://registry.yarnpkg.com/concat-map/-/concat-map-0.0.1.tgz#d8a96bd77fd68df7793a73036a3ba0d5405d477b"
 
-concat-stream@^1.4.10, concat-stream@^1.5.0, concat-stream@^1.5.1:
+concat-stream@^1.4.10, concat-stream@^1.5.0:
+  version "1.6.1"
+  resolved "https://registry.yarnpkg.com/concat-stream/-/concat-stream-1.6.1.tgz#261b8f518301f1d834e36342b9fea095d2620a26"
+  dependencies:
+    inherits "^2.0.3"
+    readable-stream "^2.2.2"
+    typedarray "^0.0.6"
+
+concat-stream@^1.5.1:
   version "1.6.2"
   resolved "https://registry.yarnpkg.com/concat-stream/-/concat-stream-1.6.2.tgz#904bdf194cd3122fc675c77fc4ac3d4ff0fd1a34"
   dependencies:
@@ -10139,14 +10143,14 @@ semver-sort@0.0.4:
     semver "^5.0.3"
     semver-regex "^1.0.0"
 
-"semver@2 || 3 || 4 || 5", semver@5.5.0, semver@^5.0.3, semver@^5.1.0, semver@^5.3.0, semver@^5.4.1, semver@^5.5.0:
-  version "5.5.0"
-  resolved "https://registry.yarnpkg.com/semver/-/semver-5.5.0.tgz#dc4bbc7a6ca9d916dee5d43516f0092b58f7b8ab"
-
-semver@5.4.1, semver@~5.4.1:
+"semver@2 || 3 || 4 || 5", semver@5.4.1, semver@^5.0.3, semver@^5.1.0, semver@^5.3.0, semver@^5.4.1, semver@~5.4.1:
   version "5.4.1"
   resolved "https://registry.yarnpkg.com/semver/-/semver-5.4.1.tgz#e059c09d8571f0540823733433505d3a2f00b18e"
 
+semver@5.5.0, semver@^5.5.0:
+  version "5.5.0"
+  resolved "https://registry.yarnpkg.com/semver/-/semver-5.5.0.tgz#dc4bbc7a6ca9d916dee5d43516f0092b58f7b8ab"
+
 semver@^4.1.0:
   version "4.3.6"
   resolved "https://registry.yarnpkg.com/semver/-/semver-4.3.6.tgz#300bc6e0e86374f7ba61068b5b1ecd57fc6532da"