update tests

contracts/dev-utils/test/order_validation_utils.ts

@@ -94,7 +94,7 @@ describe('OrderValidationUtils/OrderTransferSimulatorUtils', () => {
             txDefaults,
             artifacts,
         );
-        const exchangeWrapper = new ExchangeWrapper(exchange, provider);
+        const exchangeWrapper = new ExchangeWrapper(exchange);
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(multiAssetProxy.address, owner);

contracts/exchange-forwarder/contracts/src/MixinExchangeWrapper.sol

@@ -57,26 +57,12 @@ contract MixinExchangeWrapper is
         );
 
         address exchange = address(EXCHANGE);
+        (bool didSucceed, bytes memory returnData) = exchange.call(fillOrderCalldata);
+        if (didSucceed) {
+            assert(returnData.length == 160);
+            fillResults = abi.decode(returnData, (LibFillResults.FillResults));
+        }
 
-        // Call `fillOrder` and handle any exceptions gracefully
-        assembly {
-            let success := call(
-                gas,                                // forward all gas
-                exchange,                           // call address of Exchange contract
-                0,                                  // transfer 0 wei
-                add(fillOrderCalldata, 32),         // pointer to start of input (skip array length in first 32 bytes)
-                mload(fillOrderCalldata),           // length of input
-                fillOrderCalldata,                  // write output over input
-                160                                 // output size is 160 bytes
-            )
-            if success {
-                mstore(fillResults, mload(fillOrderCalldata))
-                mstore(add(fillResults, 32), mload(add(fillOrderCalldata, 32)))
-                mstore(add(fillResults, 64), mload(add(fillOrderCalldata, 64)))
-                mstore(add(fillResults, 96), mload(add(fillOrderCalldata, 96)))
-                mstore(add(fillResults, 128), mload(add(fillOrderCalldata, 128)))
-            }
-        }
         // fillResults values will be 0 by default if call was unsuccessful
         return fillResults;
     }
@@ -99,12 +85,14 @@ contract MixinExchangeWrapper is
             uint256 makerAssetAcquiredAmount
         )
     {
-        // No fee or percentage fee
+        uint256 protocolFee = tx.gasprice.safeMul(EXCHANGE.protocolFeeMultiplier());
+
+        // No taker fee or percentage fee
         if (order.takerFee == 0 || order.takerFeeAssetData.equals(order.makerAssetData)) {
             // Attempt to sell the remaining amount of WETH
             LibFillResults.FillResults memory singleFillResults = _fillOrderNoThrow(
                 order,
-                remainingTakerAssetFillAmount,
+                remainingTakerAssetFillAmount.safeSub(protocolFee),
                 signature
             );
 
@@ -118,14 +106,13 @@ contract MixinExchangeWrapper is
             );
         // WETH fee
         } else if (order.takerFeeAssetData.equals(order.takerAssetData)) {
-            uint256 protocolFee = tx.gasprice.safeMul(EXCHANGE.protocolFeeMultiplier());
 
             // We will first sell WETH as the takerAsset, then use it to pay the takerFee.
-            // This ensures that we reserve enough to pay the fee.
+            // This ensures that we reserve enough to pay the taker and protocol fees.
             uint256 takerAssetFillAmount = LibMath.getPartialAmountCeil(
                 order.takerAssetAmount,
-                order.takerAssetAmount.safeAdd(order.takerFee).safeAdd(protocolFee),
+                order.takerAssetAmount.safeAdd(order.takerFee),
-                remainingTakerAssetFillAmount
+                remainingTakerAssetFillAmount.safeSub(protocolFee)
             );
 
             LibFillResults.FillResults memory singleFillResults = _fillOrderNoThrow(
@@ -222,7 +209,7 @@ contract MixinExchangeWrapper is
             uint256 makerAssetAcquiredAmount
         )
     {
-        // No fee or WETH fee
+        // No taker fee or WETH fee
         if (order.takerFee == 0 || order.takerFeeAssetData.equals(order.takerAssetData)) {
             // Calculate the remaining amount of takerAsset to sell
             uint256 remainingTakerAssetFillAmount = LibMath.getPartialAmountCeil(
@@ -238,7 +225,7 @@ contract MixinExchangeWrapper is
                 signature
             );
 
-            // WETH is also spent on the taker fee, so we add it here.
+            // WETH is also spent on the protocol and taker fees, so we add it here.
             wethSpentAmount = singleFillResults.takerAssetFilledAmount.safeAdd(
                 singleFillResults.takerFeePaid
             ).safeAdd(

contracts/exchange-forwarder/contracts/src/MixinWeth.sol

@@ -47,19 +47,19 @@ contract MixinWeth is
         internal
     {
         if (msg.value == 0) {
-            LibRichErrors.rrevert(LibForwarderRichErrors.MsgValueCantEqualZeroError());
+            LibRichErrors.rrevert(LibForwarderRichErrors.MsgValueCannotEqualZeroError());
         }
         ETHER_TOKEN.deposit.value(msg.value)();
     }
 
     /// @dev Transfers feePercentage of WETH spent on primary orders to feeRecipient.
     ///      Refunds any excess ETH to msg.sender.
-    /// @param wethSold Amount of WETH sold when filling primary orders.
+    /// @param wethSpent Amount of WETH spent when filling orders.
     /// @param feePercentage Percentage of WETH sold that will payed as fee to forwarding contract feeRecipient.
     /// @param feeRecipient Address that will receive ETH when orders are filled.
     /// @return ethFee Amount paid to feeRecipient as a percentage fee on the total WETH sold.
     function _transferEthFeeAndRefund(
-        uint256 wethSold,
+        uint256 wethSpent,
         uint256 feePercentage,
         address payable feeRecipient
     )
@@ -73,22 +73,22 @@ contract MixinWeth is
             ));
         }
 
-        // Ensure that no extra WETH owned by this contract has been sold.
+        // Ensure that no extra WETH owned by this contract has been spent.
-        if (wethSold > msg.value) {
+        if (wethSpent > msg.value) {
-            LibRichErrors.rrevert(LibForwarderRichErrors.OversoldWethError(
+            LibRichErrors.rrevert(LibForwarderRichErrors.OverspentWethError(
-                wethSold,
+                wethSpent,
                 msg.value
             ));
         }
 
-        // Calculate amount of WETH that hasn't been sold.
+        // Calculate amount of WETH that hasn't been spent.
-        uint256 wethRemaining = msg.value.safeSub(wethSold);
+        uint256 wethRemaining = msg.value.safeSub(wethSpent);
 
         // Calculate ETH fee to pay to feeRecipient.
         ethFee = LibMath.getPartialAmountFloor(
             feePercentage,
             PERCENTAGE_DENOMINATOR,
-            wethSold
+            wethSpent
         );
 
         // Ensure fee is less than amount of WETH remaining.

contracts/exchange-forwarder/contracts/src/libs/LibConstants.sol

@@ -21,7 +21,6 @@ pragma solidity ^0.5.9;
 import "@0x/contracts-utils/contracts/src/LibBytes.sol";
 import "@0x/contracts-exchange/contracts/src/interfaces/IExchange.sol";
 import "@0x/contracts-erc20/contracts/src/interfaces/IEtherToken.sol";
-import "@0x/contracts-erc20/contracts/src/interfaces/IERC20Token.sol";
 
 
 contract LibConstants {

contracts/exchange-forwarder/contracts/src/libs/LibForwarderRichErrors.sol

@@ -51,9 +51,9 @@ library LibForwarderRichErrors {
     bytes4 internal constant INSUFFICIENT_ETH_FOR_FEE_ERROR_SELECTOR =
         0xecf40fd9;
 
-    // bytes4(keccak256("OversoldWethError(uint256,uint256)"))
+    // bytes4(keccak256("OverspentWethError(uint256,uint256)"))
-    bytes4 internal constant OVERSOLD_WETH_ERROR_SELECTOR =
+    bytes4 internal constant OVERSPENT_WETH_ERROR_SELECTOR =
-        0x5cc555c8;
+        0xcdcbed5d;
 
     // bytes4(keccak256("TransferFailedError(bytes)"))
     bytes4 internal constant TRANSFER_FAILED_ERROR_SELECTOR =
@@ -63,9 +63,9 @@ library LibForwarderRichErrors {
     bytes4 internal constant DEFAULT_FUNCTION_WETH_CONTRACT_ONLY_ERROR_SELECTOR =
         0x08b18698;
 
-    // bytes4(keccak256("MsgValueCantEqualZeroError()"))
+    // bytes4(keccak256("MsgValueCannotEqualZeroError()"))
-    bytes4 internal constant MSG_VALUE_CANT_EQUAL_ZERO_ERROR_SELECTOR =
+    bytes4 internal constant MSG_VALUE_CANNOT_EQUAL_ZERO_ERROR_SELECTOR =
-        0x1213e1d6;
+        0x8c0e562b;
 
     // bytes4(keccak256("Erc721AmountMustEqualOneError(uint256)"))
     bytes4 internal constant ERC721_AMOUNT_MUST_EQUAL_ONE_ERROR_SELECTOR =
@@ -164,8 +164,8 @@ library LibForwarderRichErrors {
         );
     }
 
-    function OversoldWethError(
+    function OverspentWethError(
-        uint256 wethSold,
+        uint256 wethSpent,
         uint256 msgValue
     )
         internal
@@ -173,8 +173,8 @@ library LibForwarderRichErrors {
         returns (bytes memory)
     {
         return abi.encodeWithSelector(
-            OVERSOLD_WETH_ERROR_SELECTOR,
+            OVERSPENT_WETH_ERROR_SELECTOR,
-            wethSold,
+            wethSpent,
             msgValue
         );
     }
@@ -205,12 +205,12 @@ library LibForwarderRichErrors {
         );
     }
 
-    function MsgValueCantEqualZeroError()
+    function MsgValueCannotEqualZeroError()
         internal
         pure
         returns (bytes memory)
     {
-        return abi.encodeWithSelector(MSG_VALUE_CANT_EQUAL_ZERO_ERROR_SELECTOR);
+        return abi.encodeWithSelector(MSG_VALUE_CANNOT_EQUAL_ZERO_ERROR_SELECTOR);
     }
 
     function Erc721AmountMustEqualOneError(

contracts/exchange-forwarder/contracts/src/test/TestProtocolFeeCollector.sol

@@ -0,0 +1,70 @@
+/*
+
+  Copyright 2019 ZeroEx Intl.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+*/
+
+pragma solidity ^0.5.9;
+pragma experimental ABIEncoderV2;
+
+import "@0x/contracts-asset-proxy/contracts/src/interfaces/IAssetData.sol";
+import "@0x/contracts-asset-proxy/contracts/src/interfaces/IAssetProxy.sol";
+import "@0x/contracts-erc20/contracts/src/interfaces/IERC20Token.sol";
+
+
+ // solhint-disable no-unused-vars
+contract TestProtocolFeeCollector {
+
+    address private _wethAddress;
+    address private _wethAssetProxyAddress;
+
+    constructor (
+        address wethAddress,
+        address wethAssetProxyAddress
+    )
+        public
+    {
+        _wethAddress = wethAddress;
+        _wethAssetProxyAddress = wethAssetProxyAddress;
+    }
+
+    /// @dev Pays a protocol fee in WETH (Forwarder orders will always pay protocol fees in WETH).
+    /// @param makerAddress The address of the order's maker.
+    /// @param payerAddress The address of the protocol fee payer.
+    /// @param protocolFeePaid The protocol fee that should be paid.
+    function payProtocolFee(
+        address makerAddress,
+        address payerAddress,
+        uint256 protocolFeePaid
+    )
+        external
+        payable
+    {
+        assert(msg.value == 0);
+
+        IAssetProxy wethAssetProxy = IAssetProxy(_wethAssetProxyAddress);
+        bytes memory wethAssetData = abi.encodeWithSelector(
+            IAssetData(address(0)).ERC20Token.selector,
+            _wethAddress
+        );
+        // Transfer the protocol fee to this address in WETH.
+        wethAssetProxy.transferFrom(
+            wethAssetData,
+            payerAddress,
+            address(this),
+            protocolFeePaid
+        );
+    }
+}

contracts/exchange-forwarder/package.json

@@ -11,6 +11,7 @@
     },
     "scripts": {
         "build": "yarn pre_build && tsc -b",
+        "build:ts": "tsc -b",
         "build:ci": "yarn build",
         "pre_build": "run-s compile contracts:gen generate_contract_wrappers",
         "test": "yarn run_mocha",
@@ -34,7 +35,7 @@
         "compile:truffle": "truffle compile"
     },
     "config": {
-        "abis": "./generated-artifacts/@(Forwarder|IAssets|IForwarder|IForwarderCore|LibConstants|LibForwarderRichErrors|MixinAssets|MixinExchangeWrapper|MixinForwarderCore|MixinWeth).json",
+        "abis": "./generated-artifacts/@(Forwarder|IAssets|IForwarder|IForwarderCore|LibConstants|LibForwarderRichErrors|MixinAssets|MixinExchangeWrapper|MixinForwarderCore|MixinWeth|TestProtocolFeeCollector).json",
         "abis:comment": "This list is auto-generated by contracts-gen. Don't edit manually."
     },
     "repository": {

contracts/exchange-forwarder/src/artifacts.ts

@@ -15,6 +15,7 @@ import * as MixinAssets from '../generated-artifacts/MixinAssets.json';
 import * as MixinExchangeWrapper from '../generated-artifacts/MixinExchangeWrapper.json';
 import * as MixinForwarderCore from '../generated-artifacts/MixinForwarderCore.json';
 import * as MixinWeth from '../generated-artifacts/MixinWeth.json';
+import * as TestProtocolFeeCollector from '../generated-artifacts/TestProtocolFeeCollector.json';
 export const artifacts = {
     Forwarder: Forwarder as ContractArtifact,
     MixinAssets: MixinAssets as ContractArtifact,
@@ -26,4 +27,5 @@ export const artifacts = {
     IForwarderCore: IForwarderCore as ContractArtifact,
     LibConstants: LibConstants as ContractArtifact,
     LibForwarderRichErrors: LibForwarderRichErrors as ContractArtifact,
+    TestProtocolFeeCollector: TestProtocolFeeCollector as ContractArtifact,
 };

contracts/exchange-forwarder/src/wrappers.ts

@@ -13,3 +13,4 @@ export * from '../generated-wrappers/mixin_assets';
 export * from '../generated-wrappers/mixin_exchange_wrapper';
 export * from '../generated-wrappers/mixin_forwarder_core';
 export * from '../generated-wrappers/mixin_weth';
+export * from '../generated-wrappers/test_protocol_fee_collector';

contracts/exchange-forwarder/test/forwarder.ts

@@ -14,21 +14,24 @@ import {
 import { assetDataUtils, ForwarderRevertErrors } from '@0x/order-utils';
 import { BigNumber } from '@0x/utils';
 import { Web3Wrapper } from '@0x/web3-wrapper';
-import { TransactionReceiptWithDecodedLogs } from 'ethereum-types';
 
-import { artifacts, ForwarderContract, ForwarderTestFactory, ForwarderWrapper } from '../src';
+import {
+    artifacts,
+    ForwarderContract,
+    ForwarderTestFactory,
+    ForwarderWrapper,
+    TestProtocolFeeCollectorContract,
+} from '../src';
 
 const DECIMALS_DEFAULT = 18;
 
 blockchainTests(ContractName.Forwarder, env => {
-    let chainId: number;
-    let makerAddress: string;
     let owner: string;
+    let makerAddress: string;
     let takerAddress: string;
     let orderFeeRecipientAddress: string;
     let forwarderFeeRecipientAddress: string;
     let defaultMakerAssetAddress: string;
-    let wethAssetData: string;
 
     let weth: DummyERC20TokenContract;
     let erc20Token: DummyERC20TokenContract;
@@ -36,22 +39,26 @@ blockchainTests(ContractName.Forwarder, env => {
     let erc721Token: DummyERC721TokenContract;
     let forwarderContract: ForwarderContract;
     let wethContract: WETH9Contract;
+    let exchangeContract: ExchangeContract;
+    let protocolFeeCollector: TestProtocolFeeCollectorContract;
+
     let forwarderWrapper: ForwarderWrapper;
     let exchangeWrapper: ExchangeWrapper;
+    let erc20Wrapper: ERC20Wrapper;
 
     let orderFactory: OrderFactory;
     let forwarderTestFactory: ForwarderTestFactory;
-    let erc20Wrapper: ERC20Wrapper;
-    let tx: TransactionReceiptWithDecodedLogs;
 
+    let chainId: number;
+    let wethAssetData: string;
     let erc721MakerAssetIds: BigNumber[];
-    const gasPrice = new BigNumber(constants.DEFAULT_GAS_PRICE);
+
+    const GAS_PRICE = new BigNumber(env.txDefaults.gasPrice || constants.DEFAULT_GAS_PRICE);
+    const PROTOCOL_FEE_MULTIPLIER = new BigNumber(150);
+    const PROTOCOL_FEE = GAS_PRICE.times(PROTOCOL_FEE_MULTIPLIER);
 
     before(async () => {
-        await env.blockchainLifecycle.startAsync();
+        // Set up addresses
-
-        chainId = await env.getChainIdAsync();
-
         const accounts = await env.getAccountAddressesAsync();
         const usedAddresses = ([
             owner,
@@ -61,24 +68,27 @@ blockchainTests(ContractName.Forwarder, env => {
             forwarderFeeRecipientAddress,
         ] = accounts);
 
-        const erc721Wrapper = new ERC721Wrapper(env.provider, usedAddresses, owner);
+        // Set up Exchange
-        erc20Wrapper = new ERC20Wrapper(env.provider, usedAddresses, owner);
+        chainId = await env.getChainIdAsync();
-
+        exchangeContract = await ExchangeContract.deployFrom0xArtifactAsync(
-        const numDummyErc20ToDeploy = 2;
+            exchangeArtifacts.Exchange,
-        [erc20Token, secondErc20Token] = await erc20Wrapper.deployDummyTokensAsync(
+            env.provider,
-            numDummyErc20ToDeploy,
+            env.txDefaults,
-            constants.DUMMY_TOKEN_DECIMALS,
+            {},
+            new BigNumber(chainId),
         );
+        exchangeWrapper = new ExchangeWrapper(exchangeContract);
 
+        // Set up ERC20
+        erc20Wrapper = new ERC20Wrapper(env.provider, usedAddresses, owner);
+        [erc20Token, secondErc20Token] = await erc20Wrapper.deployDummyTokensAsync(2, constants.DUMMY_TOKEN_DECIMALS);
         const erc20Proxy = await erc20Wrapper.deployProxyAsync();
-        await erc20Wrapper.setBalancesAndAllowancesAsync();
+        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
-
+        await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeContract.address, {
-        [erc721Token] = await erc721Wrapper.deployDummyTokensAsync();
+            from: owner,
-        const erc721Proxy = await erc721Wrapper.deployProxyAsync();
+        });
-        await erc721Wrapper.setBalancesAndAllowancesAsync();
-        const erc721Balances = await erc721Wrapper.getBalancesAsync();
-        erc721MakerAssetIds = erc721Balances[makerAddress][erc721Token.address];
 
+        // Set up WETH
         wethContract = await WETH9Contract.deployFrom0xArtifactAsync(
             erc20Artifacts.WETH9,
             env.provider,
@@ -86,59 +96,68 @@ blockchainTests(ContractName.Forwarder, env => {
             {},
         );
         weth = new DummyERC20TokenContract(wethContract.address, env.provider);
-        erc20Wrapper.addDummyTokenContract(weth);
-
         wethAssetData = assetDataUtils.encodeERC20AssetData(wethContract.address);
-        const exchangeInstance = await ExchangeContract.deployFrom0xArtifactAsync(
+        erc20Wrapper.addDummyTokenContract(weth);
-            exchangeArtifacts.Exchange,
+        await erc20Wrapper.setBalancesAndAllowancesAsync();
+
+        // Set up ERC721
+        const erc721Wrapper = new ERC721Wrapper(env.provider, usedAddresses, owner);
+        [erc721Token] = await erc721Wrapper.deployDummyTokensAsync();
+        const erc721Proxy = await erc721Wrapper.deployProxyAsync();
+        await erc721Wrapper.setBalancesAndAllowancesAsync();
+        const erc721Balances = await erc721Wrapper.getBalancesAsync();
+        erc721MakerAssetIds = erc721Balances[makerAddress][erc721Token.address];
+        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
+        await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeContract.address, {
+            from: owner,
+        });
+
+        // Set up Protocol Fee Collector
+        protocolFeeCollector = await TestProtocolFeeCollectorContract.deployFrom0xArtifactAsync(
+            artifacts.TestProtocolFeeCollector,
             env.provider,
             env.txDefaults,
             {},
-            new BigNumber(chainId),
+            wethContract.address,
+            erc20Proxy.address,
         );
-        exchangeWrapper = new ExchangeWrapper(exchangeInstance, env.provider);
+        await exchangeContract.setProtocolFeeMultiplier.awaitTransactionSuccessAsync(PROTOCOL_FEE_MULTIPLIER);
-        await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
+        await exchangeContract.setProtocolFeeCollectorAddress.awaitTransactionSuccessAsync(
-        await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
+            protocolFeeCollector.address,
-
+        );
-        await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeInstance.address, {
+        await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(protocolFeeCollector.address, {
-            from: owner,
-        });
-        await erc721Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeInstance.address, {
             from: owner,
         });
 
+        // Set defaults
         defaultMakerAssetAddress = erc20Token.address;
-        const defaultTakerAssetAddress = wethContract.address;
         const defaultOrderParams = {
             makerAddress,
             feeRecipientAddress: orderFeeRecipientAddress,
-            makerAssetData: assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
-            takerAssetData: assetDataUtils.encodeERC20AssetData(defaultTakerAssetAddress),
             makerAssetAmount: Web3Wrapper.toBaseUnitAmount(200, DECIMALS_DEFAULT),
             takerAssetAmount: Web3Wrapper.toBaseUnitAmount(10, DECIMALS_DEFAULT),
-            makerFeeAssetData: assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
-            takerFeeAssetData: assetDataUtils.encodeERC20AssetData(defaultMakerAssetAddress),
             makerFee: Web3Wrapper.toBaseUnitAmount(0, DECIMALS_DEFAULT),
             takerFee: Web3Wrapper.toBaseUnitAmount(0, DECIMALS_DEFAULT),
-            exchangeAddress: exchangeInstance.address,
+            exchangeAddress: exchangeContract.address,
             chainId,
         };
-        const privateKey = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(makerAddress)];
-        orderFactory = new OrderFactory(privateKey, defaultOrderParams);
 
+        // Set up Forwarder
         forwarderContract = await ForwarderContract.deployFrom0xArtifactAsync(
             artifacts.Forwarder,
             env.provider,
             env.txDefaults,
             {},
-            exchangeInstance.address,
+            exchangeContract.address,
             wethAssetData,
         );
         forwarderWrapper = new ForwarderWrapper(forwarderContract, env.provider);
-
         await forwarderWrapper.approveMakerAssetProxyAsync(defaultOrderParams.makerAssetData, { from: takerAddress });
         erc20Wrapper.addTokenOwnerAddress(forwarderContract.address);
 
+        // Set up factories
+        const privateKey = constants.TESTRPC_PRIVATE_KEYS[accounts.indexOf(makerAddress)];
+        orderFactory = new OrderFactory(privateKey, defaultOrderParams);
         forwarderTestFactory = new ForwarderTestFactory(
             exchangeWrapper,
             forwarderWrapper,
@@ -146,16 +165,18 @@ blockchainTests(ContractName.Forwarder, env => {
             forwarderContract.address,
             makerAddress,
             takerAddress,
+            protocolFeeCollector.address,
             orderFeeRecipientAddress,
             forwarderFeeRecipientAddress,
             weth.address,
-            gasPrice,
+            GAS_PRICE,
+            PROTOCOL_FEE_MULTIPLIER,
         );
     });
 
     blockchainTests.resets('constructor', () => {
         it('should revert if assetProxy is unregistered', async () => {
-            const exchangeInstance = await ExchangeContract.deployFrom0xArtifactAsync(
+            const exchange = await ExchangeContract.deployFrom0xArtifactAsync(
                 exchangeArtifacts.Exchange,
                 env.provider,
                 env.txDefaults,
@@ -168,7 +189,7 @@ blockchainTests(ContractName.Forwarder, env => {
                 env.provider,
                 env.txDefaults,
                 {},
-                exchangeInstance.address,
+                exchange.address,
                 wethAssetData,
             ) as any) as sendTransactionResult;
 
@@ -223,7 +244,7 @@ blockchainTests(ContractName.Forwarder, env => {
             const takerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(takerAddress);
 
             // Execute test case
-            tx = await forwarderWrapper.marketSellOrdersWithEthAsync([order], {
+            const tx = await forwarderWrapper.marketSellOrdersWithEthAsync([order], {
                 value: ethValue,
                 from: takerAddress,
             });
@@ -231,7 +252,7 @@ blockchainTests(ContractName.Forwarder, env => {
             const takerEthBalanceAfter = await env.web3Wrapper.getBalanceInWeiAsync(takerAddress);
             const forwarderEthBalance = await env.web3Wrapper.getBalanceInWeiAsync(forwarderContract.address);
             const newBalances = await erc20Wrapper.getBalancesAsync();
-            const totalEthSpent = gasPrice.times(tx.gasUsed);
+            const totalEthSpent = GAS_PRICE.times(tx.gasUsed);
 
             // Validate test case
             expect(takerEthBalanceAfter).to.be.bignumber.equal(takerEthBalanceBefore.minus(totalEthSpent));
@@ -273,15 +294,15 @@ blockchainTests(ContractName.Forwarder, env => {
         });
         it('should refund remaining ETH if amount is greater than takerAssetAmount', async () => {
             const order = await orderFactory.newSignedOrderAsync();
-            const ethValue = order.takerAssetAmount.plus(2);
+            const ethValue = order.takerAssetAmount.plus(PROTOCOL_FEE).plus(2);
             const takerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(takerAddress);
 
-            tx = await forwarderWrapper.marketSellOrdersWithEthAsync([order], {
+            const tx = await forwarderWrapper.marketSellOrdersWithEthAsync([order], {
                 value: ethValue,
                 from: takerAddress,
             });
             const takerEthBalanceAfter = await env.web3Wrapper.getBalanceInWeiAsync(takerAddress);
-            const totalEthSpent = order.takerAssetAmount.plus(gasPrice.times(tx.gasUsed));
+            const totalEthSpent = order.takerAssetAmount.plus(PROTOCOL_FEE).plus(GAS_PRICE.times(tx.gasUsed));
 
             expect(takerEthBalanceAfter).to.be.bignumber.equal(takerEthBalanceBefore.minus(totalEthSpent));
         });
@@ -527,7 +548,7 @@ blockchainTests(ContractName.Forwarder, env => {
             const fillableOrder = await orderFactory.newSignedOrderAsync();
             await forwarderTestFactory.marketBuyTestAsync([cancelledOrder, fillableOrder], 1.5, erc20Token);
         });
-        it('Should buy slightly greater MakerAsset when exchange rate is rounded', async () => {
+        it('Should buy slightly greater makerAsset when exchange rate is rounded', async () => {
             // The 0x Protocol contracts round the exchange rate in favor of the Maker.
             // In this case, the taker must round up how much they're going to spend, which
             // in turn increases the amount of MakerAsset being purchased.
@@ -553,13 +574,14 @@ blockchainTests(ContractName.Forwarder, env => {
             });
             const desiredMakerAssetFillAmount = new BigNumber('5');
             const makerAssetFillAmount = new BigNumber('6');
-            const ethValue = new BigNumber('4');
+            const primaryTakerAssetFillAmount = new BigNumber('4');
+            const ethValue = primaryTakerAssetFillAmount.plus(PROTOCOL_FEE);
 
             const erc20Balances = await erc20Wrapper.getBalancesAsync();
             const takerEthBalanceBefore = await env.web3Wrapper.getBalanceInWeiAsync(takerAddress);
 
             // Execute test case
-            tx = await forwarderWrapper.marketBuyOrdersWithEthAsync([order], desiredMakerAssetFillAmount, {
+            const tx = await forwarderWrapper.marketBuyOrdersWithEthAsync([order], desiredMakerAssetFillAmount, {
                 value: ethValue,
                 from: takerAddress,
             });
@@ -567,8 +589,7 @@ blockchainTests(ContractName.Forwarder, env => {
             const takerEthBalanceAfter = await env.web3Wrapper.getBalanceInWeiAsync(takerAddress);
             const forwarderEthBalance = await env.web3Wrapper.getBalanceInWeiAsync(forwarderContract.address);
             const newBalances = await erc20Wrapper.getBalancesAsync();
-            const primaryTakerAssetFillAmount = ethValue;
+            const totalEthSpent = ethValue.plus(GAS_PRICE.times(tx.gasUsed));
-            const totalEthSpent = primaryTakerAssetFillAmount.plus(gasPrice.times(tx.gasUsed));
             // Validate test case
             expect(makerAssetFillAmount).to.be.bignumber.greaterThan(desiredMakerAssetFillAmount);
             expect(takerEthBalanceAfter).to.be.bignumber.equal(takerEthBalanceBefore.minus(totalEthSpent));
@@ -588,6 +609,8 @@ blockchainTests(ContractName.Forwarder, env => {
             expect(forwarderEthBalance).to.be.bignumber.equal(constants.ZERO_AMOUNT);
         });
         it('Should buy slightly greater MakerAsset when exchange rate is rounded (Regression Test)', async () => {
+            // Disable protocol fees for regression test
+            await exchangeContract.setProtocolFeeCollectorAddress.awaitTransactionSuccessAsync(constants.NULL_ADDRESS);
             // Order taken from a transaction on mainnet that failed due to a rounding error.
             const order = await orderFactory.newSignedOrderAsync({
                 makerAssetAmount: new BigNumber('268166666666666666666'),
@@ -608,7 +631,7 @@ blockchainTests(ContractName.Forwarder, env => {
                 .times(order.makerAssetAmount)
                 .dividedToIntegerBy(order.takerAssetAmount);
             // Execute test case
-            tx = await forwarderWrapper.marketBuyOrdersWithEthAsync([order], desiredMakerAssetFillAmount, {
+            const tx = await forwarderWrapper.marketBuyOrdersWithEthAsync([order], desiredMakerAssetFillAmount, {
                 value: ethValue,
                 from: takerAddress,
             });
@@ -617,7 +640,7 @@ blockchainTests(ContractName.Forwarder, env => {
             const forwarderEthBalance = await env.web3Wrapper.getBalanceInWeiAsync(forwarderContract.address);
             const newBalances = await erc20Wrapper.getBalancesAsync();
             const primaryTakerAssetFillAmount = ethValue;
-            const totalEthSpent = primaryTakerAssetFillAmount.plus(gasPrice.times(tx.gasUsed));
+            const totalEthSpent = primaryTakerAssetFillAmount.plus(GAS_PRICE.times(tx.gasUsed));
             // Validate test case
             expect(makerAssetFillAmount).to.be.bignumber.greaterThan(desiredMakerAssetFillAmount);
             expect(takerEthBalanceAfter).to.be.bignumber.equal(takerEthBalanceBefore.minus(totalEthSpent));
@@ -661,7 +684,7 @@ blockchainTests(ContractName.Forwarder, env => {
             const order = await orderFactory.newSignedOrderAsync();
             const forwarderFeePercentage = new BigNumber(2);
             const ethFee = ForwarderTestFactory.getPercentageOfValue(
-                order.takerAssetAmount.times(0.5),
+                order.takerAssetAmount.times(0.5).plus(PROTOCOL_FEE),
                 forwarderFeePercentage,
             );
 

contracts/exchange-forwarder/test/utils/forwarder_test_factory.ts

@@ -2,118 +2,31 @@ import { ERC20Wrapper } from '@0x/contracts-asset-proxy';
 import { DummyERC20TokenContract } from '@0x/contracts-erc20';
 import { DummyERC721TokenContract } from '@0x/contracts-erc721';
 import { ExchangeWrapper } from '@0x/contracts-exchange';
-import { chaiSetup, constants, ERC20BalancesByOwner, OrderStatus, web3Wrapper } from '@0x/contracts-test-utils';
+import { constants, ERC20BalancesByOwner, expect, OrderStatus, web3Wrapper } from '@0x/contracts-test-utils';
 import { OrderInfo, SignedOrder } from '@0x/types';
 import { BigNumber, RevertError } from '@0x/utils';
-import * as chai from 'chai';
 import * as _ from 'lodash';
 
 import { ForwarderWrapper } from './forwarder_wrapper';
 
-chaiSetup.configure();
-const expect = chai.expect;
-
 // Necessary bookkeeping to validate Forwarder results
 interface ForwarderFillState {
     takerAssetFillAmount: BigNumber;
     makerAssetFillAmount: BigNumber;
+    protocolFees: BigNumber;
     wethFees: BigNumber;
     percentageFees: BigNumber;
     maxOversoldWeth: BigNumber;
     maxOverboughtMakerAsset: BigNumber;
 }
 
-// Simulates filling some orders via the Forwarder contract. For example, if
-// orders = [A, B, C, D] and fractionalNumberOfOrdersToFill = 2.3, then
-// we simulate A and B being completely filled, and 0.3 * C being filled.
-function computeExpectedResults(
-    orders: SignedOrder[],
-    ordersInfoBefore: OrderInfo[],
-    fractionalNumberOfOrdersToFill: number,
-): ForwarderFillState {
-    const currentState = {
-        takerAssetFillAmount: constants.ZERO_AMOUNT,
-        makerAssetFillAmount: constants.ZERO_AMOUNT,
-        wethFees: constants.ZERO_AMOUNT,
-        percentageFees: constants.ZERO_AMOUNT,
-        maxOversoldWeth: constants.ZERO_AMOUNT,
-        maxOverboughtMakerAsset: constants.ZERO_AMOUNT,
-    };
-    let remainingOrdersToFill = fractionalNumberOfOrdersToFill;
-
-    for (const [i, order] of orders.entries()) {
-        if (remainingOrdersToFill === 0) {
-            break;
-        }
-
-        if (ordersInfoBefore[i].orderStatus !== OrderStatus.Fillable) {
-            // If the order is not fillable, skip over it but still count it towards fractionalNumberOfOrdersToFill
-            remainingOrdersToFill = Math.max(remainingOrdersToFill - 1, 0);
-            continue;
-        }
-
-        let makerAssetAmount;
-        let takerAssetAmount;
-        let takerFee;
-        if (remainingOrdersToFill < 1) {
-            makerAssetAmount = order.makerAssetAmount.times(remainingOrdersToFill).integerValue();
-            takerAssetAmount = order.takerAssetAmount.times(remainingOrdersToFill).integerValue();
-            takerFee = order.takerFee.times(remainingOrdersToFill).integerValue();
-
-            // Up to 1 wei worth of WETH will be oversold on the last order due to rounding
-            currentState.maxOversoldWeth = new BigNumber(1);
-            // Equivalently, up to 1 wei worth of maker asset will be overbought
-            currentState.maxOverboughtMakerAsset = currentState.maxOversoldWeth
-                .times(order.makerAssetAmount)
-                .dividedToIntegerBy(order.takerAssetAmount);
-        } else {
-            makerAssetAmount = order.makerAssetAmount;
-            takerAssetAmount = order.takerAssetAmount;
-            takerFee = order.takerFee;
-        }
-
-        // Accounting for partially filled orders
-        // As with unfillable orders, these still count as 1 towards fractionalNumberOfOrdersToFill
-        const takerAssetFilled = ordersInfoBefore[i].orderTakerAssetFilledAmount;
-        const makerAssetFilled = takerAssetFilled
-            .times(order.makerAssetAmount)
-            .dividedToIntegerBy(order.takerAssetAmount);
-        takerAssetAmount = BigNumber.max(takerAssetAmount.minus(takerAssetFilled), constants.ZERO_AMOUNT);
-        makerAssetAmount = BigNumber.max(makerAssetAmount.minus(makerAssetFilled), constants.ZERO_AMOUNT);
-
-        currentState.takerAssetFillAmount = currentState.takerAssetFillAmount.plus(takerAssetAmount);
-        currentState.makerAssetFillAmount = currentState.makerAssetFillAmount.plus(makerAssetAmount);
-
-        if (order.takerFeeAssetData === order.makerAssetData) {
-            currentState.percentageFees = currentState.percentageFees.plus(takerFee);
-        } else if (order.takerFeeAssetData === order.takerAssetData) {
-            currentState.wethFees = currentState.wethFees.plus(takerFee);
-        }
-
-        remainingOrdersToFill = Math.max(remainingOrdersToFill - 1, 0);
-    }
-
-    return currentState;
-}
-
 // Since bignumber is not compatible with chai's within
-function expectBalanceWithin(balance: BigNumber, low: BigNumber, high: BigNumber): void {
+function expectBalanceWithin(balance: BigNumber, low: BigNumber, high: BigNumber, message?: string): void {
-    expect(balance).to.be.bignumber.gte(low);
+    expect(balance, message).to.be.bignumber.gte(low);
-    expect(balance).to.be.bignumber.lte(high);
+    expect(balance, message).to.be.bignumber.lte(high);
 }
 
 export class ForwarderTestFactory {
-    private readonly _exchangeWrapper: ExchangeWrapper;
-    private readonly _forwarderWrapper: ForwarderWrapper;
-    private readonly _erc20Wrapper: ERC20Wrapper;
-    private readonly _forwarderAddress: string;
-    private readonly _makerAddress: string;
-    private readonly _takerAddress: string;
-    private readonly _orderFeeRecipientAddress: string;
-    private readonly _forwarderFeeRecipientAddress: string;
-    private readonly _wethAddress: string;
-    private readonly _gasPrice: BigNumber;
-
     public static getPercentageOfValue(value: BigNumber, percentage: BigNumber): BigNumber {
         const numerator = constants.PERCENTAGE_DENOMINATOR.times(percentage).dividedToIntegerBy(100);
         const newValue = value.times(numerator).dividedToIntegerBy(constants.PERCENTAGE_DENOMINATOR);
@@ -121,28 +34,19 @@ export class ForwarderTestFactory {
     }
 
     constructor(
-        exchangeWrapper: ExchangeWrapper,
+        private readonly _exchangeWrapper: ExchangeWrapper,
-        forwarderWrapper: ForwarderWrapper,
+        private readonly _forwarderWrapper: ForwarderWrapper,
-        erc20Wrapper: ERC20Wrapper,
+        private readonly _erc20Wrapper: ERC20Wrapper,
-        forwarderAddress: string,
+        private readonly _forwarderAddress: string,
-        makerAddress: string,
+        private readonly _makerAddress: string,
-        takerAddress: string,
+        private readonly _takerAddress: string,
-        orderFeeRecipientAddress: string,
+        private readonly _protocolFeeCollectorAddress: string,
-        forwarderFeeRecipientAddress: string,
+        private readonly _orderFeeRecipientAddress: string,
-        wethAddress: string,
+        private readonly _forwarderFeeRecipientAddress: string,
-        gasPrice: BigNumber,
+        private readonly _wethAddress: string,
-    ) {
+        private readonly _gasPrice: BigNumber,
-        this._exchangeWrapper = exchangeWrapper;
+        private readonly _protocolFeeMultiplier: BigNumber,
-        this._forwarderWrapper = forwarderWrapper;
+    ) {}
-        this._erc20Wrapper = erc20Wrapper;
-        this._forwarderAddress = forwarderAddress;
-        this._makerAddress = makerAddress;
-        this._takerAddress = takerAddress;
-        this._orderFeeRecipientAddress = orderFeeRecipientAddress;
-        this._forwarderFeeRecipientAddress = forwarderFeeRecipientAddress;
-        this._wethAddress = wethAddress;
-        this._gasPrice = gasPrice;
-    }
 
     public async marketBuyTestAsync(
         orders: SignedOrder[],
@@ -167,22 +71,18 @@ export class ForwarderTestFactory {
         const ordersInfoBefore = await Promise.all(orders.map(order => this._exchangeWrapper.getOrderInfoAsync(order)));
         const orderStatusesBefore = ordersInfoBefore.map(orderInfo => orderInfo.orderStatus);
 
-        const expectedResults = computeExpectedResults(orders, ordersInfoBefore, fractionalNumberOfOrdersToFill);
+        const expectedResults = this._computeExpectedResults(orders, ordersInfoBefore, fractionalNumberOfOrdersToFill);
-        const ethSpentOnForwarderFee = ForwarderTestFactory.getPercentageOfValue(
+        const wethSpent = expectedResults.takerAssetFillAmount
-            expectedResults.takerAssetFillAmount,
+            .plus(expectedResults.protocolFees)
-            forwarderFeePercentage,
+            .plus(expectedResults.wethFees)
-        );
+            .plus(expectedResults.maxOversoldWeth);
+        const ethSpentOnForwarderFee = ForwarderTestFactory.getPercentageOfValue(wethSpent, forwarderFeePercentage);
+        const ethValue = wethSpent.plus(ethSpentOnForwarderFee).plus(ethValueAdjustment);
+
         const feePercentage = ForwarderTestFactory.getPercentageOfValue(
             constants.PERCENTAGE_DENOMINATOR,
             forwarderFeePercentage,
         );
-
-        const ethValue = expectedResults.takerAssetFillAmount
-            .plus(expectedResults.wethFees)
-            .plus(expectedResults.maxOversoldWeth)
-            .plus(ethSpentOnForwarderFee)
-            .plus(ethValueAdjustment);
-
         const tx = this._forwarderWrapper.marketBuyOrdersWithEthAsync(
             orders,
             expectedResults.makerAssetFillAmount.minus(expectedResults.percentageFees),
@@ -240,21 +140,20 @@ export class ForwarderTestFactory {
         const ordersInfoBefore = await Promise.all(orders.map(order => this._exchangeWrapper.getOrderInfoAsync(order)));
         const orderStatusesBefore = ordersInfoBefore.map(orderInfo => orderInfo.orderStatus);
 
-        const expectedResults = computeExpectedResults(orders, ordersInfoBefore, fractionalNumberOfOrdersToFill);
+        const expectedResults = this._computeExpectedResults(orders, ordersInfoBefore, fractionalNumberOfOrdersToFill);
-        const ethSpentOnForwarderFee = ForwarderTestFactory.getPercentageOfValue(
+        const wethSpent = expectedResults.takerAssetFillAmount
-            expectedResults.takerAssetFillAmount,
+            .plus(expectedResults.protocolFees)
-            forwarderFeePercentage,
+            .plus(expectedResults.wethFees)
-        );
+            .plus(expectedResults.maxOversoldWeth);
+
+        const ethSpentOnForwarderFee = ForwarderTestFactory.getPercentageOfValue(wethSpent, forwarderFeePercentage);
+        const ethValue = wethSpent.plus(ethSpentOnForwarderFee);
+
         const feePercentage = ForwarderTestFactory.getPercentageOfValue(
             constants.PERCENTAGE_DENOMINATOR,
             forwarderFeePercentage,
         );
 
-        const ethValue = expectedResults.takerAssetFillAmount
-            .plus(expectedResults.wethFees)
-            .plus(expectedResults.maxOversoldWeth)
-            .plus(ethSpentOnForwarderFee);
-
         const tx = this._forwarderWrapper.marketSellOrdersWithEthAsync(
             orders,
             {
@@ -268,10 +167,9 @@ export class ForwarderTestFactory {
             await expect(tx).to.revertWith(options.revertError);
         } else {
             const gasUsed = (await tx).gasUsed;
-            const ordersInfoAfter = await Promise.all(
+            const orderStatusesAfter = await Promise.all(
-                orders.map(order => this._exchangeWrapper.getOrderInfoAsync(order)),
+                orders.map(async order => (await this._exchangeWrapper.getOrderInfoAsync(order)).orderStatus),
             );
-            const orderStatusesAfter = ordersInfoAfter.map(orderInfo => orderInfo.orderStatus);
 
             await this._checkResultsAsync(
                 fractionalNumberOfOrdersToFill,
@@ -303,6 +201,7 @@ export class ForwarderTestFactory {
                 .minus(expectedResults.makerAssetFillAmount)
                 .minus(expectedResults.maxOverboughtMakerAsset),
             oldBalances[this._makerAddress][makerAssetAddress].minus(expectedResults.makerAssetFillAmount),
+            'Maker makerAsset balance',
         );
         expectBalanceWithin(
             newBalances[this._takerAddress][makerAssetAddress],
@@ -313,11 +212,18 @@ export class ForwarderTestFactory {
                 .plus(expectedResults.makerAssetFillAmount)
                 .minus(expectedResults.percentageFees)
                 .plus(expectedResults.maxOverboughtMakerAsset),
+            'Taker makerAsset balance',
         );
-        expect(newBalances[this._orderFeeRecipientAddress][makerAssetAddress]).to.be.bignumber.equal(
+        expect(
+            newBalances[this._orderFeeRecipientAddress][makerAssetAddress],
+            'Order fee recipient makerAsset balance',
+        ).to.be.bignumber.equal(
             oldBalances[this._orderFeeRecipientAddress][makerAssetAddress].plus(expectedResults.percentageFees),
         );
-        expect(newBalances[this._forwarderAddress][makerAssetAddress]).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+        expect(
+            newBalances[this._forwarderAddress][makerAssetAddress],
+            'Forwarder contract makerAsset balance',
+        ).to.be.bignumber.equal(constants.ZERO_AMOUNT);
     }
 
     private async _checkResultsAsync(
@@ -340,18 +246,17 @@ export class ForwarderTestFactory {
             if (fractionalNumberOfOrdersToFill >= i + 1 && orderStatusesBefore[i] === OrderStatus.Fillable) {
                 expectedOrderStatus = OrderStatus.FullyFilled;
             }
-
+            expect(orderStatus, ` Order ${i} status`).to.equal(expectedOrderStatus);
-            expect(orderStatus).to.equal(expectedOrderStatus);
         }
 
+        const wethSpent = expectedResults.takerAssetFillAmount
+            .plus(expectedResults.protocolFees)
+            .plus(expectedResults.wethFees);
         const ethSpentOnForwarderFee = ForwarderTestFactory.getPercentageOfValue(
-            expectedResults.takerAssetFillAmount,
+            wethSpent,
             options.forwarderFeePercentage || constants.ZERO_AMOUNT,
         );
-        const totalEthSpent = expectedResults.takerAssetFillAmount
+        const totalEthSpent = wethSpent.plus(ethSpentOnForwarderFee).plus(this._gasPrice.times(gasUsed));
-            .plus(expectedResults.wethFees)
-            .plus(ethSpentOnForwarderFee)
-            .plus(this._gasPrice.times(gasUsed));
 
         const takerEthBalanceAfter = await web3Wrapper.getBalanceInWeiAsync(this._takerAddress);
         const forwarderEthBalance = await web3Wrapper.getBalanceInWeiAsync(this._forwarderAddress);
@@ -361,12 +266,13 @@ export class ForwarderTestFactory {
             takerEthBalanceAfter,
             takerEthBalanceBefore.minus(totalEthSpent).minus(expectedResults.maxOversoldWeth),
             takerEthBalanceBefore.minus(totalEthSpent),
+            'Taker ETH balance',
         );
         if (options.forwarderFeeRecipientEthBalanceBefore !== undefined) {
             const fowarderFeeRecipientEthBalanceAfter = await web3Wrapper.getBalanceInWeiAsync(
                 this._forwarderFeeRecipientAddress,
             );
-            expect(fowarderFeeRecipientEthBalanceAfter).to.be.bignumber.equal(
+            expect(fowarderFeeRecipientEthBalanceAfter, 'Forwarder fee recipient ETH balance').to.be.bignumber.equal(
                 options.forwarderFeeRecipientEthBalanceBefore.plus(ethSpentOnForwarderFee),
             );
         }
@@ -375,7 +281,7 @@ export class ForwarderTestFactory {
             this._checkErc20Balances(erc20Balances, newBalances, expectedResults, makerAssetContract);
         } else if (options.makerAssetId !== undefined) {
             const newOwner = await makerAssetContract.ownerOf.callAsync(options.makerAssetId);
-            expect(newOwner).to.be.bignumber.equal(this._takerAddress);
+            expect(newOwner, 'New ERC721 owner').to.be.bignumber.equal(this._takerAddress);
         }
 
         expectBalanceWithin(
@@ -384,12 +290,97 @@ export class ForwarderTestFactory {
             erc20Balances[this._makerAddress][this._wethAddress]
                 .plus(expectedResults.takerAssetFillAmount)
                 .plus(expectedResults.maxOversoldWeth),
+            'Maker WETH balance',
         );
-        expect(newBalances[this._orderFeeRecipientAddress][this._wethAddress]).to.be.bignumber.equal(
+        expect(
+            newBalances[this._orderFeeRecipientAddress][this._wethAddress],
+            'Order fee recipient WETH balance',
+        ).to.be.bignumber.equal(
             erc20Balances[this._orderFeeRecipientAddress][this._wethAddress].plus(expectedResults.wethFees),
         );
-
+        expect(
-        expect(newBalances[this._forwarderAddress][this._wethAddress]).to.be.bignumber.equal(constants.ZERO_AMOUNT);
+            newBalances[this._forwarderAddress][this._wethAddress],
+            'Forwarder contract WETH balance',
+        ).to.be.bignumber.equal(constants.ZERO_AMOUNT);
         expect(forwarderEthBalance).to.be.bignumber.equal(constants.ZERO_AMOUNT);
     }
+
+    // Simulates filling some orders via the Forwarder contract. For example, if
+    // orders = [A, B, C, D] and fractionalNumberOfOrdersToFill = 2.3, then
+    // we simulate A and B being completely filled, and 0.3 * C being filled.
+    private _computeExpectedResults(
+        orders: SignedOrder[],
+        ordersInfoBefore: OrderInfo[],
+        fractionalNumberOfOrdersToFill: number,
+    ): ForwarderFillState {
+        const currentState = {
+            takerAssetFillAmount: constants.ZERO_AMOUNT,
+            makerAssetFillAmount: constants.ZERO_AMOUNT,
+            protocolFees: constants.ZERO_AMOUNT,
+            wethFees: constants.ZERO_AMOUNT,
+            percentageFees: constants.ZERO_AMOUNT,
+            maxOversoldWeth: constants.ZERO_AMOUNT,
+            maxOverboughtMakerAsset: constants.ZERO_AMOUNT,
+        };
+        let remainingOrdersToFill = fractionalNumberOfOrdersToFill;
+
+        for (const [i, order] of orders.entries()) {
+            if (remainingOrdersToFill === 0) {
+                break;
+            }
+
+            if (ordersInfoBefore[i].orderStatus !== OrderStatus.Fillable) {
+                // If the order is not fillable, skip over it but still count it towards fractionalNumberOfOrdersToFill
+                remainingOrdersToFill = Math.max(remainingOrdersToFill - 1, 0);
+                continue;
+            }
+
+            let makerAssetAmount;
+            let takerAssetAmount;
+            let takerFee;
+            if (remainingOrdersToFill < 1) {
+                makerAssetAmount = order.makerAssetAmount.times(remainingOrdersToFill).integerValue();
+                takerAssetAmount = order.takerAssetAmount.times(remainingOrdersToFill).integerValue();
+                takerFee = order.takerFee.times(remainingOrdersToFill).integerValue();
+
+                // Up to 1 wei worth of WETH will be oversold on the last order due to rounding
+                currentState.maxOversoldWeth = new BigNumber(1);
+                // Equivalently, up to 1 wei worth of maker asset will be overbought
+                currentState.maxOverboughtMakerAsset = currentState.maxOversoldWeth
+                    .times(order.makerAssetAmount)
+                    .dividedToIntegerBy(order.takerAssetAmount);
+            } else {
+                makerAssetAmount = order.makerAssetAmount;
+                takerAssetAmount = order.takerAssetAmount;
+                takerFee = order.takerFee;
+            }
+
+            // Accounting for partially filled orders
+            // As with unfillable orders, these still count as 1 towards fractionalNumberOfOrdersToFill
+            const takerAssetFilled = ordersInfoBefore[i].orderTakerAssetFilledAmount;
+            const makerAssetFilled = takerAssetFilled
+                .times(order.makerAssetAmount)
+                .dividedToIntegerBy(order.takerAssetAmount);
+            takerAssetAmount = BigNumber.max(takerAssetAmount.minus(takerAssetFilled), constants.ZERO_AMOUNT);
+            makerAssetAmount = BigNumber.max(makerAssetAmount.minus(makerAssetFilled), constants.ZERO_AMOUNT);
+
+            currentState.takerAssetFillAmount = currentState.takerAssetFillAmount.plus(takerAssetAmount);
+            currentState.makerAssetFillAmount = currentState.makerAssetFillAmount.plus(makerAssetAmount);
+
+            if (this._protocolFeeCollectorAddress !== constants.NULL_ADDRESS) {
+                currentState.protocolFees = currentState.protocolFees.plus(
+                    this._gasPrice.times(this._protocolFeeMultiplier),
+                );
+            }
+            if (order.takerFeeAssetData === order.makerAssetData) {
+                currentState.percentageFees = currentState.percentageFees.plus(takerFee);
+            } else if (order.takerFeeAssetData === order.takerAssetData) {
+                currentState.wethFees = currentState.wethFees.plus(takerFee);
+            }
+
+            remainingOrdersToFill = Math.max(remainingOrdersToFill - 1, 0);
+        }
+
+        return currentState;
+    }
 }

contracts/exchange-forwarder/tsconfig.json

@@ -12,7 +12,8 @@
         "generated-artifacts/MixinAssets.json",
         "generated-artifacts/MixinExchangeWrapper.json",
         "generated-artifacts/MixinForwarderCore.json",
-        "generated-artifacts/MixinWeth.json"
+        "generated-artifacts/MixinWeth.json",
+        "generated-artifacts/TestProtocolFeeCollector.json"
     ],
     "exclude": ["./deploy/solc/solc_bin"]
 }

contracts/exchange/test/core.ts

@@ -172,7 +172,7 @@ blockchainTests.resets('Exchange core', () => {
         await multiAssetProxy.registerAssetProxy.awaitTransactionSuccessAsync(staticCallProxy.address, { from: owner });
 
         // Configure Exchange
-        exchangeWrapper = new ExchangeWrapper(exchange, provider);
+        exchangeWrapper = new ExchangeWrapper(exchange);
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(erc1155Proxy.address, owner);

contracts/exchange/test/match_orders.ts

@@ -135,7 +135,7 @@ describe('matchOrders', () => {
             {},
             new BigNumber(chainId),
         );
-        exchangeWrapper = new ExchangeWrapper(exchange, provider);
+        exchangeWrapper = new ExchangeWrapper(exchange);
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(erc1155Proxy.address, owner);

contracts/exchange/test/transactions.ts

@@ -96,7 +96,7 @@ blockchainTests.resets('Exchange transactions', env => {
             {},
             new BigNumber(chainId),
         );
-        exchangeWrapper = new ExchangeWrapper(exchangeInstance, env.provider);
+        exchangeWrapper = new ExchangeWrapper(exchangeInstance);
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
 
         await erc20Proxy.addAuthorizedAddress.awaitTransactionSuccessAsync(exchangeInstance.address, { from: owner });

contracts/exchange/test/utils/exchange_wrapper.ts

@@ -1,4 +1,4 @@
-import { BatchMatchOrder, orderUtils, Web3ProviderEngine } from '@0x/contracts-test-utils';
+import { BatchMatchOrder, orderUtils } from '@0x/contracts-test-utils';
 import {
     BatchMatchedFillResults,
     FillResults,
@@ -8,7 +8,7 @@ import {
     SignedZeroExTransaction,
 } from '@0x/types';
 import { AbiEncoder, BigNumber } from '@0x/utils';
-import { MethodAbi, TransactionReceiptWithDecodedLogs, ZeroExProvider } from 'ethereum-types';
+import { MethodAbi, TransactionReceiptWithDecodedLogs } from 'ethereum-types';
 import * as _ from 'lodash';
 
 import { ExchangeContract } from '../../src';
@@ -16,18 +16,15 @@ import { ExchangeContract } from '../../src';
 import { AbiDecodedFillOrderData } from './types';
 
 export class ExchangeWrapper {
-    private readonly _exchange: ExchangeContract;
+    constructor(public readonly exchangeContract: ExchangeContract) {}
-    // tslint:disable no-unused-variable
+
-    constructor(exchangeContract: ExchangeContract, provider: Web3ProviderEngine | ZeroExProvider) {
-        this._exchange = exchangeContract;
-    }
     public async fillOrderAsync(
         signedOrder: SignedOrder,
         from: string,
         opts: { takerAssetFillAmount?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
-        const txReceipt = await this._exchange.fillOrder.awaitTransactionSuccessAsync(
+        const txReceipt = await this.exchangeContract.fillOrder.awaitTransactionSuccessAsync(
             params.order,
             params.takerAssetFillAmount,
             params.signature,
@@ -37,7 +34,7 @@ export class ExchangeWrapper {
     }
     public async cancelOrderAsync(signedOrder: SignedOrder, from: string): Promise<TransactionReceiptWithDecodedLogs> {
         const params = orderUtils.createCancel(signedOrder);
-        const txReceipt = await this._exchange.cancelOrder.awaitTransactionSuccessAsync(params.order, { from });
+        const txReceipt = await this.exchangeContract.cancelOrder.awaitTransactionSuccessAsync(params.order, { from });
         return txReceipt;
     }
     public async fillOrKillOrderAsync(
@@ -46,7 +43,7 @@ export class ExchangeWrapper {
         opts: { takerAssetFillAmount?: BigNumber; gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
-        const txReceipt = await this._exchange.fillOrKillOrder.awaitTransactionSuccessAsync(
+        const txReceipt = await this.exchangeContract.fillOrKillOrder.awaitTransactionSuccessAsync(
             params.order,
             params.takerAssetFillAmount,
             params.signature,
@@ -59,7 +56,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { takerAssetFillAmounts?: BigNumber[]; gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.batchFillOrders.awaitTransactionSuccessAsync(
+        return this.exchangeContract.batchFillOrders.awaitTransactionSuccessAsync(
             orders,
             opts.takerAssetFillAmounts === undefined
                 ? orders.map(signedOrder => signedOrder.takerAssetAmount)
@@ -73,7 +70,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { takerAssetFillAmounts?: BigNumber[]; gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.batchFillOrKillOrders.awaitTransactionSuccessAsync(
+        return this.exchangeContract.batchFillOrKillOrders.awaitTransactionSuccessAsync(
             orders,
             opts.takerAssetFillAmounts === undefined
                 ? orders.map(signedOrder => signedOrder.takerAssetAmount)
@@ -87,7 +84,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { takerAssetFillAmounts?: BigNumber[]; gas?: number; gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.batchFillOrdersNoThrow.awaitTransactionSuccessAsync(
+        return this.exchangeContract.batchFillOrdersNoThrow.awaitTransactionSuccessAsync(
             orders,
             opts.takerAssetFillAmounts === undefined
                 ? orders.map(signedOrder => signedOrder.takerAssetAmount)
@@ -101,7 +98,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { takerAssetFillAmount: BigNumber; gas?: number; gasPrice?: BigNumber },
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.marketSellOrdersNoThrow.awaitTransactionSuccessAsync(
+        return this.exchangeContract.marketSellOrdersNoThrow.awaitTransactionSuccessAsync(
             orders,
             opts.takerAssetFillAmount,
             orders.map(signedOrder => signedOrder.signature),
@@ -113,7 +110,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { makerAssetFillAmount: BigNumber; gas?: number; gasPrice?: BigNumber },
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.marketBuyOrdersNoThrow.awaitTransactionSuccessAsync(
+        return this.exchangeContract.marketBuyOrdersNoThrow.awaitTransactionSuccessAsync(
             orders,
             opts.makerAssetFillAmount,
             orders.map(signedOrder => signedOrder.signature),
@@ -125,7 +122,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { takerAssetFillAmount: BigNumber; gas?: number },
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.marketSellOrdersFillOrKill.awaitTransactionSuccessAsync(
+        return this.exchangeContract.marketSellOrdersFillOrKill.awaitTransactionSuccessAsync(
             orders,
             opts.takerAssetFillAmount,
             orders.map(signedOrder => signedOrder.signature),
@@ -137,7 +134,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { makerAssetFillAmount: BigNumber; gas?: number },
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.marketBuyOrdersFillOrKill.awaitTransactionSuccessAsync(
+        return this.exchangeContract.marketBuyOrdersFillOrKill.awaitTransactionSuccessAsync(
             orders,
             opts.makerAssetFillAmount,
             orders.map(signedOrder => signedOrder.signature),
@@ -148,19 +145,22 @@ export class ExchangeWrapper {
         orders: SignedOrder[],
         from: string,
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.batchCancelOrders.awaitTransactionSuccessAsync(orders, { from });
+        return this.exchangeContract.batchCancelOrders.awaitTransactionSuccessAsync(orders, { from });
     }
     public async cancelOrdersUpToAsync(salt: BigNumber, from: string): Promise<TransactionReceiptWithDecodedLogs> {
-        const txReceipt = await this._exchange.cancelOrdersUpTo.awaitTransactionSuccessAsync(salt, { from });
+        const txReceipt = await this.exchangeContract.cancelOrdersUpTo.awaitTransactionSuccessAsync(salt, { from });
         return txReceipt;
     }
     public async registerAssetProxyAsync(
         assetProxyAddress: string,
         from: string,
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        const txReceipt = await this._exchange.registerAssetProxy.awaitTransactionSuccessAsync(assetProxyAddress, {
+        const txReceipt = await this.exchangeContract.registerAssetProxy.awaitTransactionSuccessAsync(
+            assetProxyAddress,
+            {
                 from,
-        });
+            },
+        );
         return txReceipt;
     }
     public async executeTransactionAsync(
@@ -168,7 +168,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.executeTransaction.awaitTransactionSuccessAsync(
+        return this.exchangeContract.executeTransaction.awaitTransactionSuccessAsync(
             signedTransaction,
             signedTransaction.signature,
             { from, gasPrice: opts.gasPrice },
@@ -180,25 +180,29 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const signatures = signedTransactions.map(signedTransaction => signedTransaction.signature);
-        return this._exchange.batchExecuteTransactions.awaitTransactionSuccessAsync(signedTransactions, signatures, {
+        return this.exchangeContract.batchExecuteTransactions.awaitTransactionSuccessAsync(
+            signedTransactions,
+            signatures,
+            {
                 from,
                 gasPrice: opts.gasPrice,
-        });
+            },
+        );
     }
     public async getTakerAssetFilledAmountAsync(orderHashHex: string): Promise<BigNumber> {
-        const filledAmount = await this._exchange.filled.callAsync(orderHashHex);
+        const filledAmount = await this.exchangeContract.filled.callAsync(orderHashHex);
         return filledAmount;
     }
     public async isCancelledAsync(orderHashHex: string): Promise<boolean> {
-        const isCancelled = await this._exchange.cancelled.callAsync(orderHashHex);
+        const isCancelled = await this.exchangeContract.cancelled.callAsync(orderHashHex);
         return isCancelled;
     }
     public async getOrderEpochAsync(makerAddress: string, senderAddress: string): Promise<BigNumber> {
-        const orderEpoch = await this._exchange.orderEpoch.callAsync(makerAddress, senderAddress);
+        const orderEpoch = await this.exchangeContract.orderEpoch.callAsync(makerAddress, senderAddress);
         return orderEpoch;
     }
     public async getOrderInfoAsync(signedOrder: SignedOrder): Promise<OrderInfo> {
-        const orderInfo = await this._exchange.getOrderInfo.callAsync(signedOrder);
+        const orderInfo = await this.exchangeContract.getOrderInfo.callAsync(signedOrder);
         return orderInfo;
     }
     public async batchMatchOrdersAsync(
@@ -208,7 +212,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const params = orderUtils.createBatchMatchOrders(signedOrdersLeft, signedOrdersRight);
-        return this._exchange.batchMatchOrders.awaitTransactionSuccessAsync(
+        return this.exchangeContract.batchMatchOrders.awaitTransactionSuccessAsync(
             params.leftOrders,
             params.rightOrders,
             params.leftSignatures,
@@ -221,7 +225,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.batchMatchOrders.awaitTransactionSuccessAsync(
+        return this.exchangeContract.batchMatchOrders.awaitTransactionSuccessAsync(
             params.leftOrders,
             params.rightOrders,
             params.leftSignatures,
@@ -236,7 +240,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<BatchMatchedFillResults> {
         const params = orderUtils.createBatchMatchOrders(signedOrdersLeft, signedOrdersRight);
-        const batchMatchedFillResults = await this._exchange.batchMatchOrders.callAsync(
+        const batchMatchedFillResults = await this.exchangeContract.batchMatchOrders.callAsync(
             params.leftOrders,
             params.rightOrders,
             params.leftSignatures,
@@ -252,7 +256,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const params = orderUtils.createBatchMatchOrders(signedOrdersLeft, signedOrdersRight);
-        return this._exchange.batchMatchOrdersWithMaximalFill.awaitTransactionSuccessAsync(
+        return this.exchangeContract.batchMatchOrdersWithMaximalFill.awaitTransactionSuccessAsync(
             params.leftOrders,
             params.rightOrders,
             params.leftSignatures,
@@ -265,7 +269,7 @@ export class ExchangeWrapper {
         from: string,
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        return this._exchange.batchMatchOrdersWithMaximalFill.awaitTransactionSuccessAsync(
+        return this.exchangeContract.batchMatchOrdersWithMaximalFill.awaitTransactionSuccessAsync(
             params.leftOrders,
             params.rightOrders,
             params.leftSignatures,
@@ -280,7 +284,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<BatchMatchedFillResults> {
         const params = orderUtils.createBatchMatchOrders(signedOrdersLeft, signedOrdersRight);
-        const batchMatchedFillResults = await this._exchange.batchMatchOrdersWithMaximalFill.callAsync(
+        const batchMatchedFillResults = await this.exchangeContract.batchMatchOrdersWithMaximalFill.callAsync(
             params.leftOrders,
             params.rightOrders,
             params.leftSignatures,
@@ -296,7 +300,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const params = orderUtils.createMatchOrders(signedOrderLeft, signedOrderRight);
-        const txReceipt = await this._exchange.matchOrders.awaitTransactionSuccessAsync(
+        const txReceipt = await this.exchangeContract.matchOrders.awaitTransactionSuccessAsync(
             params.left,
             params.right,
             params.leftSignature,
@@ -312,7 +316,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<MatchedFillResults> {
         const params = orderUtils.createMatchOrders(signedOrderLeft, signedOrderRight);
-        const matchedFillResults = await this._exchange.matchOrders.callAsync(
+        const matchedFillResults = await this.exchangeContract.matchOrders.callAsync(
             params.left,
             params.right,
             params.leftSignature,
@@ -328,7 +332,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber } = {},
     ): Promise<TransactionReceiptWithDecodedLogs> {
         const params = orderUtils.createMatchOrders(signedOrderLeft, signedOrderRight);
-        return this._exchange.matchOrdersWithMaximalFill.awaitTransactionSuccessAsync(
+        return this.exchangeContract.matchOrdersWithMaximalFill.awaitTransactionSuccessAsync(
             params.left,
             params.right,
             params.leftSignature,
@@ -343,7 +347,7 @@ export class ExchangeWrapper {
         opts: { gasPrice?: BigNumber },
     ): Promise<MatchedFillResults> {
         const params = orderUtils.createMatchOrders(signedOrderLeft, signedOrderRight);
-        const matchedFillResults = await this._exchange.matchOrdersWithMaximalFill.callAsync(
+        const matchedFillResults = await this.exchangeContract.matchOrdersWithMaximalFill.callAsync(
             params.left,
             params.right,
             params.leftSignature,
@@ -358,7 +362,7 @@ export class ExchangeWrapper {
         opts: { takerAssetFillAmount?: BigNumber; gasPrice?: BigNumber } = {},
     ): Promise<FillResults> {
         const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
-        const fillResults = await this._exchange.fillOrder.callAsync(
+        const fillResults = await this.exchangeContract.fillOrder.callAsync(
             params.order,
             params.takerAssetFillAmount,
             params.signature,
@@ -368,7 +372,7 @@ export class ExchangeWrapper {
     }
     public abiEncodeFillOrder(signedOrder: SignedOrder, opts: { takerAssetFillAmount?: BigNumber } = {}): string {
         const params = orderUtils.createFill(signedOrder, opts.takerAssetFillAmount);
-        const data = this._exchange.fillOrder.getABIEncodedTransactionData(
+        const data = this.exchangeContract.fillOrder.getABIEncodedTransactionData(
             params.order,
             params.takerAssetFillAmount,
             params.signature,
@@ -377,13 +381,10 @@ export class ExchangeWrapper {
     }
     public abiDecodeFillOrder(data: string): AbiDecodedFillOrderData {
         // Lookup fillOrder ABI in exchange abi
-        const fillOrderAbi = _.find(this._exchange.abi, { name: 'fillOrder' }) as MethodAbi;
+        const fillOrderAbi = _.find(this.exchangeContract.abi, { name: 'fillOrder' }) as MethodAbi;
         // Decode input data
         const abiEncoder = new AbiEncoder.Method(fillOrderAbi);
         const decodedData = abiEncoder.decode(data) as AbiDecodedFillOrderData;
         return decodedData;
     }
-    public getExchangeAddress(): string {
-        return this._exchange.address;
-    }
 }

contracts/exchange/test/utils/fill_order_combinatorial_utils.ts

@@ -117,7 +117,7 @@ export async function fillOrderCombinatorialUtilsFactoryAsync(
     );
 
     const logDecoder = new LogDecoder(web3Wrapper, artifacts);
-    const exchangeWrapper = new ExchangeWrapper(exchangeContract, provider);
+    const exchangeWrapper = new ExchangeWrapper(exchangeContract);
     await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, ownerAddress);
     await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, ownerAddress);
     await exchangeWrapper.registerAssetProxyAsync(erc1155Proxy.address, ownerAddress);
@@ -646,7 +646,7 @@ export class FillOrderCombinatorialUtils {
 
         const exchangeLogs = _.filter(
             txReceipt.logs,
-            txLog => txLog.address === this.exchangeWrapper.getExchangeAddress(),
+            txLog => txLog.address === this.exchangeWrapper.exchangeContract.address,
         );
         expect(exchangeLogs.length).to.be.equal(1, 'logs length');
         // tslint:disable-next-line:no-unnecessary-type-assertion

contracts/exchange/test/wrapper.ts

@@ -78,7 +78,7 @@ blockchainTests.resets('Exchange wrappers', env => {
             from: owner,
         });
 
-        exchangeWrapper = new ExchangeWrapper(exchange, env.provider);
+        exchangeWrapper = new ExchangeWrapper(exchange);
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
 
         await erc20Proxy.addAuthorizedAddress.awaitTransactionSuccessAsync(exchange.address, {

contracts/extensions/test/balance_threshold_filter.ts

@@ -136,7 +136,7 @@ describe(ContractName.BalanceThresholdFilter, () => {
             zrxAssetData,
             new BigNumber(chainId),
         );
-        exchangeWrapper = new ExchangeWrapper(exchangeInstance, provider);
+        exchangeWrapper = new ExchangeWrapper(exchangeInstance);
         // Register proxies
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
         await erc20Proxy.addAuthorizedAddress.sendTransactionAsync(exchangeInstance.address, {

contracts/extensions/test/dutch_auction.ts

@@ -95,7 +95,7 @@ describe(ContractName.DutchAuction, () => {
             zrxAssetData,
             new BigNumber(chainId),
         );
-        const exchangeWrapper = new ExchangeWrapper(exchangeInstance, provider);
+        const exchangeWrapper = new ExchangeWrapper(exchangeInstance);
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
 

contracts/extensions/test/order_matcher.ts

@@ -115,7 +115,7 @@ describe('OrderMatcher', () => {
             assetDataUtils.encodeERC20AssetData(zrxToken.address),
             new BigNumber(chainId),
         );
-        exchangeWrapper = new ExchangeWrapper(exchange, provider);
+        exchangeWrapper = new ExchangeWrapper(exchange);
         await exchangeWrapper.registerAssetProxyAsync(erc20Proxy.address, owner);
         await exchangeWrapper.registerAssetProxyAsync(erc721Proxy.address, owner);
         // Authorize ERC20 trades by exchange

contracts/test-utils/src/order_factory.ts

@@ -20,10 +20,10 @@ export class OrderFactory {
         const tenMinutesInSeconds = 10 * 60;
         const currentBlockTimestamp = await getLatestBlockTimestampAsync();
         const order = ({
+            takerAddress: constants.NULL_ADDRESS,
             senderAddress: constants.NULL_ADDRESS,
             expirationTimeSeconds: new BigNumber(currentBlockTimestamp).plus(tenMinutesInSeconds),
             salt: generatePseudoRandomSalt(),
-            takerAddress: constants.NULL_ADDRESS,
             ...this._defaultOrderParams,
             ...customOrderParams,
         } as any) as Order;

packages/order-utils/src/forwarder_revert_errors.ts

@@ -64,10 +64,10 @@ export class InsufficientEthForFeeError extends RevertError {
     }
 }
 
-export class OversoldWethError extends RevertError {
+export class OverspentWethError extends RevertError {
-    constructor(wethSold?: BigNumber | number | string, msgValue?: BigNumber | number | string) {
+    constructor(wethSpent?: BigNumber | number | string, msgValue?: BigNumber | number | string) {
-        super('OversoldWethError', 'OversoldWethError(uint256 wethSold, uint256 msgValue)', {
+        super('OverspentWethError', 'OverspentWethError(uint256 wethSpent, uint256 msgValue)', {
-            wethSold,
+            wethSpent,
             msgValue,
         });
     }
@@ -87,9 +87,9 @@ export class DefaultFunctionWethContractOnlyError extends RevertError {
     }
 }
 
-export class MsgValueCantEqualZeroError extends RevertError {
+export class MsgValueCannotEqualZeroError extends RevertError {
     constructor() {
-        super('MsgValueCantEqualZeroError', 'MsgValueCantEqualZeroError()', {});
+        super('MsgValueCannotEqualZeroError', 'MsgValueCannotEqualZeroError()', {});
     }
 }
 
@@ -109,10 +109,10 @@ const types = [
     UnsupportedFeeError,
     FeePercentageTooLargeError,
     InsufficientEthForFeeError,
-    OversoldWethError,
+    OverspentWethError,
     TransferFailedError,
     DefaultFunctionWethContractOnlyError,
-    MsgValueCantEqualZeroError,
+    MsgValueCannotEqualZeroError,
     Erc721AmountMustEqualOneError,
 ];
 

packages/utils/src/revert_error.ts

@@ -351,7 +351,7 @@ export function getThrownErrorRevertErrorBytes(error: Error | GanacheTransaction
             // so we do nothing.
         }
     }
-    throw new Error(`Cannot decode thrown Errror "${error.message}" as a RevertError`);
+    throw new Error(`Cannot decode thrown Error "${error.message}" as a RevertError`);
 }
 
 function isGanacheTransactionRevertError(