Merge branch 'v2-prototype' into refactor/move-spawn-switch-to-utils

* v2-prototype: (66 commits)
  Run prettier
  Remove unused variable
  Fix linting issues
  Change shouldRenderHeader prop to shouldHideHeader
  Get build and tests to pass
  typo
  Apply prettier
  Update contracts tests after rebase
  Apply various fixes based on PR feedback
  Document debug_increaseTime method and fix typo in devnet README
  Use an enum for ProviderType in contracts/src/utils/web3_wrapper
  Update contracts package README
  Update relevant changelogs
  Remove global gas estimate buffer
  Add Async suffix to relevant assertions
  Fix linter errors
  Update package.json and yarn.lock
  Update more things to work with both Geth and Ganache
  Small fixes and cleanup
  Add additional gas to calls to fillOrderNoThrow
  ...

# Conflicts:
#	packages/order-watcher/src/order_watcher/order_watcher.ts
#	packages/react-docs/src/components/type.tsx
#	packages/website/ts/components/ui/lifecycle_raised_button.tsx
#	packages/website/ts/components/wallet/wallet.tsx

16 files changed, 289 insertions, 276 deletions

diff --git a/packages/contracts/test/asset_proxy/authorizable.ts b/packages/contracts/test/asset_proxy/authorizable.ts
index e8274acb1..922baa856 100644
--- a/packages/contracts/test/asset_proxy/authorizable.ts
+++ b/packages/contracts/test/asset_proxy/authorizable.ts
@@ -1,11 +1,10 @@
-import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils';
-import { Web3Wrapper } from '@0xproject/web3-wrapper';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import * as chai from 'chai';
 import 'make-promises-safe';
-import * as Web3 from 'web3';
 
 import { MixinAuthorizableContract } from '../../src/contract_wrappers/generated/mixin_authorizable';
 import { artifacts } from '../../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { provider, txDefaults, web3Wrapper } from '../../src/utils/web3_wrapper';
@@ -44,9 +43,9 @@ describe('Authorizable', () => {
     });
     describe('addAuthorizedAddress', () => {
         it('should throw if not called by owner', async () => {
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 authorizable.addAuthorizedAddress.sendTransactionAsync(notOwner, { from: notOwner }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
         it('should allow owner to add an authorized address', async () => {
             await web3Wrapper.awaitTransactionSuccessAsync(
@@ -61,9 +60,9 @@ describe('Authorizable', () => {
                 await authorizable.addAuthorizedAddress.sendTransactionAsync(address, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 authorizable.addAuthorizedAddress.sendTransactionAsync(address, { from: owner }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
     });
 
@@ -73,11 +72,11 @@ describe('Authorizable', () => {
                 await authorizable.addAuthorizedAddress.sendTransactionAsync(address, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 authorizable.removeAuthorizedAddress.sendTransactionAsync(address, {
                     from: notOwner,
                 }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should allow owner to remove an authorized address', async () => {
@@ -96,11 +95,11 @@ describe('Authorizable', () => {
         });
 
         it('should throw if owner attempts to remove an address that is not authorized', async () => {
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 authorizable.removeAuthorizedAddress.sendTransactionAsync(address, {
                     from: owner,
                 }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
     });
 
diff --git a/packages/contracts/test/asset_proxy/proxies.ts b/packages/contracts/test/asset_proxy/proxies.ts
index faab39759..eb2a1544f 100644
--- a/packages/contracts/test/asset_proxy/proxies.ts
+++ b/packages/contracts/test/asset_proxy/proxies.ts
@@ -1,15 +1,14 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils } from '@0xproject/order-utils';
-import { AssetProxyId } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
 import * as _ from 'lodash';
-import * as Web3 from 'web3';
 
 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 { expectRevertOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
@@ -144,7 +143,7 @@ describe('Asset Transfer Proxies', () => {
                     constants.AWAIT_TRANSACTION_MINED_MS,
                 );
                 // Perform a transfer; expect this to fail.
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc20Proxy.transferFrom.sendTransactionAsync(
                         encodedProxyMetadata,
                         makerAddress,
@@ -152,7 +151,7 @@ describe('Asset Transfer Proxies', () => {
                         transferAmount,
                         { from: notAuthorized },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw if requesting address is not authorized', async () => {
@@ -160,7 +159,7 @@ describe('Asset Transfer Proxies', () => {
                 const encodedProxyMetadata = assetProxyUtils.encodeERC20ProxyData(zrxToken.address);
                 // Perform a transfer from makerAddress to takerAddress
                 const amount = new BigNumber(10);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc20Proxy.transferFrom.sendTransactionAsync(
                         encodedProxyMetadata,
                         makerAddress,
@@ -170,7 +169,7 @@ describe('Asset Transfer Proxies', () => {
                             from: notAuthorized,
                         },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
@@ -217,7 +216,7 @@ describe('Asset Transfer Proxies', () => {
                 const toAddresses = _.times(numTransfers, () => takerAddress);
                 const amounts = _.times(numTransfers, () => amount);
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc20Proxy.batchTransferFrom.sendTransactionAsync(
                         assetMetadata,
                         fromAddresses,
@@ -225,7 +224,7 @@ describe('Asset Transfer Proxies', () => {
                         amounts,
                         { from: notAuthorized },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
@@ -247,7 +246,6 @@ describe('Asset Transfer Proxies', () => {
                 const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
                 expect(ownerMakerAsset).to.be.bignumber.equal(makerAddress);
                 // Perform a transfer from makerAddress to takerAddress
-                const erc20Balances = await erc20Wrapper.getBalancesAsync();
                 const amount = new BigNumber(1);
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await erc721Proxy.transferFrom.sendTransactionAsync(
@@ -274,9 +272,8 @@ describe('Asset Transfer Proxies', () => {
                 const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
                 expect(ownerMakerAsset).to.be.bignumber.equal(makerAddress);
                 // Perform a transfer from makerAddress to takerAddress
-                const erc20Balances = await erc20Wrapper.getBalancesAsync();
                 const amount = new BigNumber(0);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc721Proxy.transferFrom.sendTransactionAsync(
                         encodedProxyMetadata,
                         makerAddress,
@@ -284,7 +281,7 @@ describe('Asset Transfer Proxies', () => {
                         amount,
                         { from: exchangeAddress },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw if transferring > 1 amount of a token', async () => {
@@ -297,9 +294,8 @@ describe('Asset Transfer Proxies', () => {
                 const ownerMakerAsset = await erc721Token.ownerOf.callAsync(erc721MakerTokenId);
                 expect(ownerMakerAsset).to.be.bignumber.equal(makerAddress);
                 // Perform a transfer from makerAddress to takerAddress
-                const erc20Balances = await erc20Wrapper.getBalancesAsync();
                 const amount = new BigNumber(500);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc721Proxy.transferFrom.sendTransactionAsync(
                         encodedProxyMetadata,
                         makerAddress,
@@ -307,7 +303,7 @@ describe('Asset Transfer Proxies', () => {
                         amount,
                         { from: exchangeAddress },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw if allowances are too low', async () => {
@@ -325,7 +321,7 @@ describe('Asset Transfer Proxies', () => {
                 );
                 // Perform a transfer; expect this to fail.
                 const amount = new BigNumber(1);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc20Proxy.transferFrom.sendTransactionAsync(
                         encodedProxyMetadata,
                         makerAddress,
@@ -335,7 +331,7 @@ describe('Asset Transfer Proxies', () => {
                             from: notAuthorized,
                         },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw if requesting address is not authorized', async () => {
@@ -346,7 +342,7 @@ describe('Asset Transfer Proxies', () => {
                 );
                 // Perform a transfer from makerAddress to takerAddress
                 const amount = new BigNumber(1);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc721Proxy.transferFrom.sendTransactionAsync(
                         encodedProxyMetadata,
                         makerAddress,
@@ -354,7 +350,7 @@ describe('Asset Transfer Proxies', () => {
                         amount,
                         { from: notAuthorized },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
@@ -404,7 +400,7 @@ describe('Asset Transfer Proxies', () => {
                 const toAddresses = _.times(numTransfers, () => takerAddress);
                 const amounts = _.times(numTransfers, () => new BigNumber(1));
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     erc721Proxy.batchTransferFrom.sendTransactionAsync(
                         assetMetadata,
                         fromAddresses,
@@ -412,7 +408,7 @@ describe('Asset Transfer Proxies', () => {
                         amounts,
                         { from: notAuthorized },
                     ),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
diff --git a/packages/contracts/test/asset_proxy_owner.ts b/packages/contracts/test/asset_proxy_owner.ts
index 4c16b5cff..692622e1e 100644
--- a/packages/contracts/test/asset_proxy_owner.ts
+++ b/packages/contracts/test/asset_proxy_owner.ts
@@ -2,9 +2,7 @@ import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
 import { LogWithDecodedArgs } from 'ethereum-types';
-import * as _ from 'lodash';
 import 'make-promises-safe';
-import * as Web3 from 'web3';
 
 import {
     AssetProxyOwnerContract,
@@ -15,15 +13,20 @@ import {
 } from '../src/contract_wrappers/generated/asset_proxy_owner';
 import { MixinAuthorizableContract } from '../src/contract_wrappers/generated/mixin_authorizable';
 import { artifacts } from '../src/utils/artifacts';
+import {
+    expectRevertOrAlwaysFailingTransactionAsync,
+    expectRevertOrContractCallFailedAsync,
+} from '../src/utils/assertions';
 import { chaiSetup } from '../src/utils/chai_setup';
 import { constants } from '../src/utils/constants';
+import { increaseTimeAndMineBlockAsync } from '../src/utils/increase_time';
 import { MultiSigWrapper } from '../src/utils/multi_sig_wrapper';
 import { provider, txDefaults, web3Wrapper } from '../src/utils/web3_wrapper';
 
 chaiSetup.configure();
 const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
-
+// tslint:disable:no-unnecessary-type-assertion
 describe('AssetProxyOwner', () => {
     let owners: string[];
     let authorized: string;
@@ -101,7 +104,7 @@ describe('AssetProxyOwner', () => {
         });
         it('should throw if a null address is included in assetProxyContracts', async () => {
             const assetProxyContractAddresses = [erc20Proxy.address, constants.NULL_ADDRESS];
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 AssetProxyOwnerContract.deployFrom0xArtifactAsync(
                     artifacts.AssetProxyOwner,
                     provider,
@@ -111,7 +114,7 @@ describe('AssetProxyOwner', () => {
                     REQUIRED_APPROVALS,
                     SECONDS_TIME_LOCKED,
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
     });
 
@@ -120,9 +123,9 @@ describe('AssetProxyOwner', () => {
             const notRemoveAuthorizedAddressData = erc20Proxy.addAuthorizedAddress.getABIEncodedTransactionData(
                 owners[0],
             );
-            return expect(
+            return expectRevertOrContractCallFailedAsync(
                 multiSig.isFunctionRemoveAuthorizedAddress.callAsync(notRemoveAuthorizedAddressData),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should return true if data is for removeAuthorizedAddress', async () => {
@@ -139,9 +142,9 @@ describe('AssetProxyOwner', () => {
     describe('registerAssetProxy', () => {
         it('should throw if not called by multisig', async () => {
             const isRegistered = true;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 multiSig.registerAssetProxy.sendTransactionAsync(erc20Proxy.address, isRegistered, { from: owners[0] }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should register an address if called by multisig after timelock', async () => {
@@ -156,11 +159,12 @@ describe('AssetProxyOwner', () => {
                 registerAssetProxyData,
                 owners[0],
             );
+
             const log = submitTxRes.logs[0] as LogWithDecodedArgs<SubmissionContractEventArgs>;
             const txId = log.args.transactionId;
 
             await multiSigWrapper.confirmTransactionAsync(txId, owners[1]);
-            await web3Wrapper.increaseTimeAsync(SECONDS_TIME_LOCKED.toNumber());
+            await increaseTimeAndMineBlockAsync(SECONDS_TIME_LOCKED.toNumber());
 
             const executeTxRes = await multiSigWrapper.executeTransactionAsync(txId, owners[0]);
             const registerLog = executeTxRes.logs[0] as LogWithDecodedArgs<AssetProxyRegistrationContractEventArgs>;
@@ -187,7 +191,7 @@ describe('AssetProxyOwner', () => {
             const txId = log.args.transactionId;
 
             await multiSigWrapper.confirmTransactionAsync(txId, owners[1]);
-            await web3Wrapper.increaseTimeAsync(SECONDS_TIME_LOCKED.toNumber());
+            await increaseTimeAndMineBlockAsync(SECONDS_TIME_LOCKED.toNumber());
 
             const executeTxRes = await multiSigWrapper.executeTransactionAsync(txId, owners[0]);
             const failureLog = executeTxRes.logs[0] as LogWithDecodedArgs<ExecutionFailureContractEventArgs>;
@@ -239,7 +243,7 @@ describe('AssetProxyOwner', () => {
 
             await multiSigWrapper.confirmTransactionAsync(erc20AddAuthorizedAddressTxId, owners[1]);
             await multiSigWrapper.confirmTransactionAsync(erc721AddAuthorizedAddressTxId, owners[1]);
-            await web3Wrapper.increaseTimeAsync(SECONDS_TIME_LOCKED.toNumber());
+            await increaseTimeAndMineBlockAsync(SECONDS_TIME_LOCKED.toNumber());
             await multiSigWrapper.executeTransactionAsync(registerAssetProxyTxId, owners[0]);
             await multiSigWrapper.executeTransactionAsync(erc20AddAuthorizedAddressTxId, owners[0]);
             await multiSigWrapper.executeTransactionAsync(erc721AddAuthorizedAddressTxId, owners[0]);
@@ -257,9 +261,9 @@ describe('AssetProxyOwner', () => {
             const log = res.logs[0] as LogWithDecodedArgs<SubmissionContractEventArgs>;
             const txId = log.args.transactionId;
 
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 multiSig.executeRemoveAuthorizedAddress.sendTransactionAsync(txId, { from: owners[1] }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw if tx destination is not registered', async () => {
@@ -276,9 +280,9 @@ describe('AssetProxyOwner', () => {
 
             await multiSigWrapper.confirmTransactionAsync(txId, owners[1]);
 
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 multiSig.executeRemoveAuthorizedAddress.sendTransactionAsync(txId, { from: owners[1] }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw if tx data is not for removeAuthorizedAddress', async () => {
@@ -296,9 +300,9 @@ describe('AssetProxyOwner', () => {
 
             await multiSigWrapper.confirmTransactionAsync(txId, owners[1]);
 
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 multiSig.executeRemoveAuthorizedAddress.sendTransactionAsync(txId, { from: owners[1] }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should execute removeAuthorizedAddress for registered address if fully confirmed', async () => {
@@ -349,9 +353,10 @@ describe('AssetProxyOwner', () => {
             const isExecuted = tx[3];
             expect(isExecuted).to.equal(true);
 
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 multiSig.executeRemoveAuthorizedAddress.sendTransactionAsync(txId, { from: owners[1] }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
     });
 });
+// tslint:enable:no-unnecessary-type-assertion
diff --git a/packages/contracts/test/ether_token.ts b/packages/contracts/test/ether_token.ts
index 4e52b658f..5fa63f8ad 100644
--- a/packages/contracts/test/ether_token.ts
+++ b/packages/contracts/test/ether_token.ts
@@ -1,11 +1,12 @@
-import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils';
-import { BigNumber, promisify } from '@0xproject/utils';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
+import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
 import 'make-promises-safe';
 
 import { WETH9Contract } from '../src/contract_wrappers/generated/weth9';
 import { artifacts } from '../src/utils/artifacts';
+import { expectInsufficientFundsAsync, expectRevertOrAlwaysFailingTransactionAsync } from '../src/utils/assertions';
 import { chaiSetup } from '../src/utils/chai_setup';
 import { constants } from '../src/utils/constants';
 import { provider, txDefaults, web3Wrapper } from '../src/utils/web3_wrapper';
@@ -45,9 +46,7 @@ describe('EtherToken', () => {
             const initEthBalance = await web3Wrapper.getBalanceInWeiAsync(account);
             const ethToDeposit = initEthBalance.plus(1);
 
-            return expect(etherToken.deposit.sendTransactionAsync({ value: ethToDeposit })).to.be.rejectedWith(
-                "ender doesn't have enough funds to send tx.",
-            );
+            return expectInsufficientFundsAsync(etherToken.deposit.sendTransactionAsync({ value: ethToDeposit }));
         });
 
         it('should convert deposited Ether to wrapped Ether tokens', async () => {
@@ -76,8 +75,8 @@ describe('EtherToken', () => {
             const initEthTokenBalance = await etherToken.balanceOf.callAsync(account);
             const ethTokensToWithdraw = initEthTokenBalance.plus(1);
 
-            return expect(etherToken.withdraw.sendTransactionAsync(ethTokensToWithdraw)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                etherToken.withdraw.sendTransactionAsync(ethTokensToWithdraw),
             );
         });
 
diff --git a/packages/contracts/test/exchange/core.ts b/packages/contracts/test/exchange/core.ts
index 91ead93f0..5ec04c4dd 100644
--- a/packages/contracts/test/exchange/core.ts
+++ b/packages/contracts/test/exchange/core.ts
@@ -1,5 +1,5 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
-import { assetProxyUtils, crypto, orderHashUtils } from '@0xproject/order-utils';
+import { assetProxyUtils, orderHashUtils } from '@0xproject/order-utils';
 import { AssetProxyId, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
@@ -18,20 +18,20 @@ import {
     FillContractEventArgs,
 } from '../../src/contract_wrappers/generated/exchange';
 import { artifacts } from '../../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 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 { ContractName, ERC20BalancesByOwner, OrderStatus } from '../../src/utils/types';
+import { ERC20BalancesByOwner } from '../../src/utils/types';
 import { provider, txDefaults, web3Wrapper } from '../../src/utils/web3_wrapper';
 
 chaiSetup.configure();
 const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
-
+// tslint:disable:no-unnecessary-type-assertion
 describe('Exchange core', () => {
     let makerAddress: string;
     let owner: string;
@@ -415,8 +415,8 @@ describe('Exchange core', () => {
                 makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(100), 18),
                 takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(200), 18),
             });
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -432,8 +432,8 @@ describe('Exchange core', () => {
             const invalidSigBuff = Buffer.concat([v, invalidR, invalidS, signatureType]);
             const invalidSigHex = `0x${invalidSigBuff.toString('hex')}`;
             signedOrder.signature = invalidSigHex;
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -442,8 +442,8 @@ describe('Exchange core', () => {
                 makerAssetAmount: new BigNumber(0),
             });
 
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -452,19 +452,19 @@ describe('Exchange core', () => {
                 takerAssetAmount: new BigNumber(0),
             });
 
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
         it('should throw if takerAssetFillAmount is 0', async () => {
             signedOrder = orderFactory.newSignedOrder();
 
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, {
                     takerAssetFillAmount: new BigNumber(0),
                 }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw if maker erc20Balances are too low to fill order', async () => {
@@ -472,8 +472,8 @@ describe('Exchange core', () => {
                 makerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(100000), 18),
             });
 
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -481,9 +481,8 @@ describe('Exchange core', () => {
             signedOrder = orderFactory.newSignedOrder({
                 takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(100000), 18),
             });
-
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -494,11 +493,8 @@ describe('Exchange core', () => {
                 }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
-            // HACK: `rejectWith` returns a "promise-like" type, but not an actual "Promise", so TSLint
-            // complains, even though we do need to `await` it. So we disable the TSLint error below.
-            // tslint:disable-next-line:await-promise
-            await expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -509,11 +505,8 @@ describe('Exchange core', () => {
                 }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
-            // HACK: `rejectWith` returns a "promise-like" type, but not an actual "Promise", so TSLint
-            // complains, even though we do need to `await` it. So we disable the TSLint error below.
-            // tslint:disable-next-line:await-promise
-            await expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -521,16 +514,16 @@ describe('Exchange core', () => {
             signedOrder = orderFactory.newSignedOrder({
                 expirationTimeSeconds: new BigNumber(Math.floor((Date.now() - 10000) / 1000)),
             });
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
 
         it('should throw if no value is filled', async () => {
             signedOrder = orderFactory.newSignedOrder();
             await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress);
-            return expect(exchangeWrapper.fillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrderAsync(signedOrder, takerAddress),
             );
         });
     });
@@ -542,8 +535,8 @@ describe('Exchange core', () => {
         });
 
         it('should throw if not sent by maker', async () => {
-            return expect(exchangeWrapper.cancelOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.cancelOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -552,8 +545,8 @@ describe('Exchange core', () => {
                 makerAssetAmount: new BigNumber(0),
             });
 
-            return expect(exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress),
             );
         });
 
@@ -562,22 +555,21 @@ describe('Exchange core', () => {
                 takerAssetAmount: new BigNumber(0),
             });
 
-            return expect(exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress),
             );
         });
 
         it('should be able to cancel a full order', async () => {
             await exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress);
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, {
                     takerAssetFillAmount: signedOrder.takerAssetAmount.div(2),
                 }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should log 1 event with correct arguments', async () => {
-            const divisor = 2;
             const res = await exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress);
             expect(res.logs).to.have.length(1);
 
@@ -593,8 +585,8 @@ describe('Exchange core', () => {
 
         it('should throw if already cancelled', async () => {
             await exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress);
-            return expect(exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress),
             );
         });
 
@@ -602,8 +594,8 @@ describe('Exchange core', () => {
             signedOrder = orderFactory.newSignedOrder({
                 expirationTimeSeconds: new BigNumber(Math.floor((Date.now() - 10000) / 1000)),
             });
-            return expect(exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.cancelOrderAsync(signedOrder, makerAddress),
             );
         });
 
@@ -619,11 +611,11 @@ describe('Exchange core', () => {
             });
 
             const fillTakerAssetAmount2 = new BigNumber(1);
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, {
                     takerAssetFillAmount: fillTakerAssetAmount2,
                 }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
     });
 
@@ -632,16 +624,16 @@ describe('Exchange core', () => {
             const makerEpoch = new BigNumber(1);
             await exchangeWrapper.cancelOrdersUpToAsync(makerEpoch, makerAddress);
             const lesserMakerEpoch = new BigNumber(0);
-            return expect(exchangeWrapper.cancelOrdersUpToAsync(lesserMakerEpoch, makerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.cancelOrdersUpToAsync(lesserMakerEpoch, makerAddress),
             );
         });
 
         it('should fail to set makerEpoch equal to existing makerEpoch', async () => {
             const makerEpoch = new BigNumber(1);
             await exchangeWrapper.cancelOrdersUpToAsync(makerEpoch, makerAddress);
-            return expect(exchangeWrapper.cancelOrdersUpToAsync(makerEpoch, makerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.cancelOrdersUpToAsync(makerEpoch, makerAddress),
             );
         });
 
@@ -675,7 +667,12 @@ describe('Exchange core', () => {
                     salt: new BigNumber(3),
                 }),
             ];
-            await exchangeWrapper.batchFillOrdersNoThrowAsync(signedOrders, takerAddress);
+            await exchangeWrapper.batchFillOrdersNoThrowAsync(signedOrders, takerAddress, {
+                // HACK(albrow): We need to hardcode the gas estimate here because
+                // the Geth gas estimator doesn't work with the way we use
+                // delegatecall and swallow errors.
+                gas: 490000,
+            });
 
             const newBalances = await erc20Wrapper.getBalancesAsync();
             const fillMakerAssetAmount = signedOrders[2].makerAssetAmount.add(signedOrders[3].makerAssetAmount);
@@ -724,6 +721,7 @@ describe('Exchange core', () => {
             expect(initialOwnerTakerAsset).to.be.bignumber.equal(takerAddress);
             // Call Exchange
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
+            // tslint:disable-next-line:no-unused-variable
             const res = await exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, { takerAssetFillAmount });
             // Verify post-conditions
             const newOwnerMakerAsset = await erc721Token.ownerOf.callAsync(makerAssetId);
@@ -749,9 +747,9 @@ describe('Exchange core', () => {
             expect(initialOwnerTakerAsset).to.be.bignumber.equal(takerAddress);
             // Call Exchange
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, { takerAssetFillAmount }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw when taker does not own the token with id takerAssetId', async () => {
@@ -771,9 +769,9 @@ describe('Exchange core', () => {
             expect(initialOwnerTakerAsset).to.be.bignumber.not.equal(takerAddress);
             // Call Exchange
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, { takerAssetFillAmount }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw when makerAssetAmount is greater than 1', async () => {
@@ -793,9 +791,9 @@ describe('Exchange core', () => {
             expect(initialOwnerTakerAsset).to.be.bignumber.equal(takerAddress);
             // Call Exchange
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, { takerAssetFillAmount }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw when takerAssetAmount is greater than 1', async () => {
@@ -815,9 +813,9 @@ describe('Exchange core', () => {
             expect(initialOwnerTakerAsset).to.be.bignumber.equal(takerAddress);
             // Call Exchange
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, { takerAssetFillAmount }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw on partial fill', async () => {
@@ -837,9 +835,9 @@ describe('Exchange core', () => {
             expect(initialOwnerTakerAsset).to.be.bignumber.equal(takerAddress);
             // Call Exchange
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.fillOrderAsync(signedOrder, takerAddress, { takerAssetFillAmount }),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should successfully fill order when makerAsset is ERC721 and takerAsset is ERC20', async () => {
@@ -922,4 +920,6 @@ describe('Exchange core', () => {
             );
         });
     });
-}); // tslint:disable-line:max-file-line-count
+});
+// tslint:disable:max-file-line-count
+// tslint:enable:no-unnecessary-type-assertion
diff --git a/packages/contracts/test/exchange/dispatcher.ts b/packages/contracts/test/exchange/dispatcher.ts
index 8bc66e3cf..7804a2db9 100644
--- a/packages/contracts/test/exchange/dispatcher.ts
+++ b/packages/contracts/test/exchange/dispatcher.ts
@@ -3,13 +3,13 @@ import { assetProxyUtils } from '@0xproject/order-utils';
 import { AssetProxyId } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
-import * as Web3 from 'web3';
 
 import { DummyERC20TokenContract } from '../../src/contract_wrappers/generated/dummy_e_r_c20_token';
 import { ERC20ProxyContract } from '../../src/contract_wrappers/generated/e_r_c20_proxy';
 import { ERC721ProxyContract } from '../../src/contract_wrappers/generated/e_r_c721_proxy';
 import { TestAssetProxyDispatcherContract } from '../../src/contract_wrappers/generated/test_asset_proxy_dispatcher';
 import { artifacts } from '../../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
@@ -23,7 +23,6 @@ const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
 describe('AssetProxyDispatcher', () => {
     let owner: string;
     let notOwner: string;
-    let notAuthorized: string;
     let makerAddress: string;
     let takerAddress: string;
 
@@ -45,7 +44,6 @@ describe('AssetProxyDispatcher', () => {
         // Setup accounts & addresses
         const accounts = await web3Wrapper.getAvailableAddressesAsync();
         const usedAddresses = ([owner, notOwner, makerAddress, takerAddress] = accounts);
-        notAuthorized = notOwner;
 
         erc20Wrapper = new ERC20Wrapper(provider, usedAddresses, owner);
         erc721Wrapper = new ERC721Wrapper(provider, usedAddresses, owner);
@@ -177,14 +175,14 @@ describe('AssetProxyDispatcher', () => {
             const proxyAddress = await assetProxyDispatcher.getAssetProxy.callAsync(AssetProxyId.ERC20);
             expect(proxyAddress).to.be.equal(erc20Proxy.address);
             // The following transaction will throw because the currentAddress is no longer constants.NULL_ADDRESS
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
                     AssetProxyId.ERC20,
                     erc20Proxy.address,
                     constants.NULL_ADDRESS,
                     { from: owner },
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should be able to reset proxy address to NULL', async () => {
@@ -218,26 +216,26 @@ describe('AssetProxyDispatcher', () => {
 
         it('should throw if requesting address is not owner', async () => {
             const prevProxyAddress = constants.NULL_ADDRESS;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
                     AssetProxyId.ERC20,
                     erc20Proxy.address,
                     prevProxyAddress,
                     { from: notOwner },
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw if attempting to register a proxy to the incorrect id', async () => {
             const prevProxyAddress = constants.NULL_ADDRESS;
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 assetProxyDispatcher.registerAssetProxy.sendTransactionAsync(
                     AssetProxyId.ERC721,
                     erc20Proxy.address,
                     prevProxyAddress,
                     { from: owner },
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
     });
 
@@ -305,9 +303,8 @@ describe('AssetProxyDispatcher', () => {
             // Construct metadata for ERC20 proxy
             const encodedProxyMetadata = assetProxyUtils.encodeERC20ProxyData(zrxToken.address);
             // Perform a transfer from makerAddress to takerAddress
-            const erc20Balances = await erc20Wrapper.getBalancesAsync();
             const amount = new BigNumber(10);
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 assetProxyDispatcher.publicDispatchTransferFrom.sendTransactionAsync(
                     encodedProxyMetadata,
                     makerAddress,
@@ -315,7 +312,7 @@ describe('AssetProxyDispatcher', () => {
                     amount,
                     { from: owner },
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
     });
 });
diff --git a/packages/contracts/test/exchange/libs.ts b/packages/contracts/test/exchange/libs.ts
index 10cb8b34e..8553e49c8 100644
--- a/packages/contracts/test/exchange/libs.ts
+++ b/packages/contracts/test/exchange/libs.ts
@@ -3,7 +3,6 @@ import { assetProxyUtils, orderHashUtils } from '@0xproject/order-utils';
 import { SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
-import ethUtil = require('ethereumjs-util');
 
 import { TestLibsContract } from '../../src/contract_wrappers/generated/test_libs';
 import { addressUtils } from '../../src/utils/address_utils';
diff --git a/packages/contracts/test/exchange/match_orders.ts b/packages/contracts/test/exchange/match_orders.ts
index 24ee794bc..7c2ae4db8 100644
--- a/packages/contracts/test/exchange/match_orders.ts
+++ b/packages/contracts/test/exchange/match_orders.ts
@@ -1,23 +1,18 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
-import { assetProxyUtils, crypto } from '@0xproject/order-utils';
-import { AssetProxyId, SignedOrder } from '@0xproject/types';
+import { assetProxyUtils } from '@0xproject/order-utils';
+import { AssetProxyId } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
-import { LogWithDecodedArgs } from 'ethereum-types';
-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 { ExchangeContract } from '../../src/contract_wrappers/generated/exchange';
 import { artifacts } from '../../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
@@ -25,13 +20,7 @@ import { ERC721Wrapper } from '../../src/utils/erc721_wrapper';
 import { ExchangeWrapper } from '../../src/utils/exchange_wrapper';
 import { MatchOrderTester } from '../../src/utils/match_order_tester';
 import { OrderFactory } from '../../src/utils/order_factory';
-import {
-    ContractName,
-    ERC20BalancesByOwner,
-    ERC721TokenIdsByOwner,
-    OrderInfo,
-    OrderStatus,
-} from '../../src/utils/types';
+import { ERC20BalancesByOwner, ERC721TokenIdsByOwner, OrderInfo, OrderStatus } from '../../src/utils/types';
 import { provider, txDefaults, web3Wrapper } from '../../src/utils/web3_wrapper';
 
 chaiSetup.configure();
@@ -64,7 +53,6 @@ describe('matchOrders', () => {
 
     let erc721LeftMakerAssetIds: BigNumber[];
     let erc721RightMakerAssetIds: BigNumber[];
-    let erc721TakerAssetIds: BigNumber[];
 
     let defaultERC20MakerAssetAddress: string;
     let defaultERC20TakerAssetAddress: string;
@@ -103,7 +91,6 @@ describe('matchOrders', () => {
         const erc721Balances = await erc721Wrapper.getBalancesAsync();
         erc721LeftMakerAssetIds = erc721Balances[makerAddressLeft][erc721Token.address];
         erc721RightMakerAssetIds = erc721Balances[makerAddressRight][erc721Token.address];
-        erc721TakerAssetIds = erc721Balances[takerAddress][erc721Token.address];
         // Depoy exchange
         exchange = await ExchangeContract.deployFrom0xArtifactAsync(
             artifacts.Exchange,
@@ -639,9 +626,9 @@ describe('matchOrders', () => {
             // Cancel left order
             await exchangeWrapper.cancelOrderAsync(signedOrderLeft, signedOrderLeft.makerAddress);
             // Match orders
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.matchOrdersAsync(signedOrderLeft, signedOrderRight, takerAddress),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('Should throw if right order is not fillable', async () => {
@@ -665,9 +652,9 @@ describe('matchOrders', () => {
             // Cancel right order
             await exchangeWrapper.cancelOrderAsync(signedOrderRight, signedOrderRight.makerAddress);
             // Match orders
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 exchangeWrapper.matchOrdersAsync(signedOrderLeft, signedOrderRight, takerAddress),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw if there is not a positive spread', async () => {
@@ -689,7 +676,7 @@ describe('matchOrders', () => {
                 feeRecipientAddress: feeRecipientAddressRight,
             });
             // Match orders
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 matchOrderTester.matchOrdersAndVerifyBalancesAsync(
                     signedOrderLeft,
                     signedOrderRight,
@@ -697,7 +684,7 @@ describe('matchOrders', () => {
                     erc20BalancesByOwner,
                     erc721TokenIdsByOwner,
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw if the left maker asset is not equal to the right taker asset ', async () => {
@@ -719,7 +706,7 @@ describe('matchOrders', () => {
                 feeRecipientAddress: feeRecipientAddressRight,
             });
             // Match orders
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 matchOrderTester.matchOrdersAndVerifyBalancesAsync(
                     signedOrderLeft,
                     signedOrderRight,
@@ -727,7 +714,7 @@ describe('matchOrders', () => {
                     erc20BalancesByOwner,
                     erc721TokenIdsByOwner,
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should throw if the right maker asset is not equal to the left taker asset', async () => {
@@ -749,7 +736,7 @@ describe('matchOrders', () => {
                 feeRecipientAddress: feeRecipientAddressRight,
             });
             // Match orders
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 matchOrderTester.matchOrdersAndVerifyBalancesAsync(
                     signedOrderLeft,
                     signedOrderRight,
@@ -757,7 +744,7 @@ describe('matchOrders', () => {
                     erc20BalancesByOwner,
                     erc721TokenIdsByOwner,
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should transfer correct amounts when left order maker asset is an ERC721 token', async () => {
diff --git a/packages/contracts/test/exchange/signature_validator.ts b/packages/contracts/test/exchange/signature_validator.ts
index 936910ee9..bc3368d5f 100644
--- a/packages/contracts/test/exchange/signature_validator.ts
+++ b/packages/contracts/test/exchange/signature_validator.ts
@@ -1,7 +1,6 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils, orderHashUtils } from '@0xproject/order-utils';
 import { SignedOrder } from '@0xproject/types';
-import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
 import ethUtil = require('ethereumjs-util');
 
diff --git a/packages/contracts/test/exchange/transactions.ts b/packages/contracts/test/exchange/transactions.ts
index f31053ad3..e24978815 100644
--- a/packages/contracts/test/exchange/transactions.ts
+++ b/packages/contracts/test/exchange/transactions.ts
@@ -1,16 +1,15 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils, generatePseudoRandomSalt } from '@0xproject/order-utils';
-import { AssetProxyId, Order, OrderWithoutExchangeAddress, SignedOrder } from '@0xproject/types';
+import { AssetProxyId, OrderWithoutExchangeAddress, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as chai from 'chai';
-import * as ethUtil from 'ethereumjs-util';
-import * as Web3 from 'web3';
 
 import { DummyERC20TokenContract } from '../../src/contract_wrappers/generated/dummy_e_r_c20_token';
 import { ERC20ProxyContract } from '../../src/contract_wrappers/generated/e_r_c20_proxy';
 import { ExchangeContract } from '../../src/contract_wrappers/generated/exchange';
 import { WhitelistContract } from '../../src/contract_wrappers/generated/whitelist';
 import { artifacts } from '../../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
@@ -18,7 +17,7 @@ import { ExchangeWrapper } from '../../src/utils/exchange_wrapper';
 import { OrderFactory } from '../../src/utils/order_factory';
 import { orderUtils } from '../../src/utils/order_utils';
 import { TransactionFactory } from '../../src/utils/transaction_factory';
-import { ERC20BalancesByOwner, OrderStatus, SignedTransaction } from '../../src/utils/types';
+import { ERC20BalancesByOwner, SignedTransaction } from '../../src/utils/types';
 import { provider, txDefaults, web3Wrapper } from '../../src/utils/web3_wrapper';
 
 chaiSetup.configure();
@@ -126,8 +125,8 @@ describe('Exchange transactions', () => {
             });
 
             it('should throw if not called by specified sender', async () => {
-                return expect(exchangeWrapper.executeTransactionAsync(signedTx, takerAddress)).to.be.rejectedWith(
-                    constants.REVERT,
+                return expectRevertOrAlwaysFailingTransactionAsync(
+                    exchangeWrapper.executeTransactionAsync(signedTx, takerAddress),
                 );
             });
 
@@ -168,8 +167,8 @@ describe('Exchange transactions', () => {
 
             it('should throw if the a 0x transaction with the same transactionHash has already been executed', async () => {
                 await exchangeWrapper.executeTransactionAsync(signedTx, senderAddress);
-                return expect(exchangeWrapper.executeTransactionAsync(signedTx, senderAddress)).to.be.rejectedWith(
-                    constants.REVERT,
+                return expectRevertOrAlwaysFailingTransactionAsync(
+                    exchangeWrapper.executeTransactionAsync(signedTx, senderAddress),
                 );
             });
 
@@ -187,15 +186,15 @@ describe('Exchange transactions', () => {
             });
 
             it('should throw if not called by specified sender', async () => {
-                return expect(exchangeWrapper.executeTransactionAsync(signedTx, makerAddress)).to.be.rejectedWith(
-                    constants.REVERT,
+                return expectRevertOrAlwaysFailingTransactionAsync(
+                    exchangeWrapper.executeTransactionAsync(signedTx, makerAddress),
                 );
             });
 
             it('should cancel the order when signed by maker and called by sender', async () => {
                 await exchangeWrapper.executeTransactionAsync(signedTx, senderAddress);
-                return expect(exchangeWrapper.fillOrderAsync(signedOrder, senderAddress)).to.be.rejectedWith(
-                    constants.REVERT,
+                return expectRevertOrAlwaysFailingTransactionAsync(
+                    exchangeWrapper.fillOrderAsync(signedOrder, senderAddress),
                 );
             });
         });
@@ -244,7 +243,7 @@ describe('Exchange transactions', () => {
             orderWithoutExchangeAddress = orderUtils.getOrderWithoutExchangeAddress(signedOrder);
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
             const salt = generatePseudoRandomSalt();
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 whitelist.fillOrderIfWhitelisted.sendTransactionAsync(
                     orderWithoutExchangeAddress,
                     takerAssetFillAmount,
@@ -252,7 +251,7 @@ describe('Exchange transactions', () => {
                     signedOrder.signature,
                     { from: takerAddress },
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should revert if taker has not been whitelisted', async () => {
@@ -264,7 +263,7 @@ describe('Exchange transactions', () => {
             orderWithoutExchangeAddress = orderUtils.getOrderWithoutExchangeAddress(signedOrder);
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
             const salt = generatePseudoRandomSalt();
-            return expect(
+            return expectRevertOrAlwaysFailingTransactionAsync(
                 whitelist.fillOrderIfWhitelisted.sendTransactionAsync(
                     orderWithoutExchangeAddress,
                     takerAssetFillAmount,
@@ -272,7 +271,7 @@ describe('Exchange transactions', () => {
                     signedOrder.signature,
                     { from: takerAddress },
                 ),
-            ).to.be.rejectedWith(constants.REVERT);
+            );
         });
 
         it('should fill the order if maker and taker have been whitelisted', async () => {
diff --git a/packages/contracts/test/exchange/wrapper.ts b/packages/contracts/test/exchange/wrapper.ts
index 583ec9f91..6a522e50e 100644
--- a/packages/contracts/test/exchange/wrapper.ts
+++ b/packages/contracts/test/exchange/wrapper.ts
@@ -1,4 +1,4 @@
-import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { assetProxyUtils } from '@0xproject/order-utils';
 import { AssetProxyId, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
@@ -6,15 +6,14 @@ import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
 import * as _ from 'lodash';
 import 'make-promises-safe';
-import * as Web3 from 'web3';
 
 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 { ExchangeContract } from '../../src/contract_wrappers/generated/exchange';
-import { TokenRegistryContract } from '../../src/contract_wrappers/generated/token_registry';
 import { artifacts } from '../../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { ERC20Wrapper } from '../../src/utils/erc20_wrapper';
@@ -172,8 +171,8 @@ describe('Exchange wrappers', () => {
                 expirationTimeSeconds: new BigNumber(Math.floor((Date.now() - 10000) / 1000)),
             });
 
-            return expect(exchangeWrapper.fillOrKillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrKillOrderAsync(signedOrder, takerAddress),
             );
         });
 
@@ -184,8 +183,8 @@ describe('Exchange wrappers', () => {
                 takerAssetFillAmount: signedOrder.takerAssetAmount.div(2),
             });
 
-            return expect(exchangeWrapper.fillOrKillOrderAsync(signedOrder, takerAddress)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                exchangeWrapper.fillOrKillOrderAsync(signedOrder, takerAddress),
             );
         });
     });
@@ -197,12 +196,16 @@ describe('Exchange wrappers', () => {
                 takerAssetAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(200), 18),
             });
             const takerAssetFillAmount = signedOrder.takerAssetAmount.div(2);
+
             await exchangeWrapper.fillOrderNoThrowAsync(signedOrder, takerAddress, {
                 takerAssetFillAmount,
+                // HACK(albrow): We need to hardcode the gas estimate here because
+                // the Geth gas estimator doesn't work with the way we use
+                // delegatecall and swallow errors.
+                gas: 250000,
             });
 
             const newBalances = await erc20Wrapper.getBalancesAsync();
-
             const makerAssetFilledAmount = takerAssetFillAmount
                 .times(signedOrder.makerAssetAmount)
                 .dividedToIntegerBy(signedOrder.takerAssetAmount);
@@ -212,6 +215,7 @@ describe('Exchange wrappers', () => {
             const takerFee = signedOrder.takerFee
                 .times(makerAssetFilledAmount)
                 .dividedToIntegerBy(signedOrder.makerAssetAmount);
+
             expect(newBalances[makerAddress][defaultMakerAssetAddress]).to.be.bignumber.equal(
                 erc20Balances[makerAddress][defaultMakerAssetAddress].minus(makerAssetFilledAmount),
             );
@@ -360,7 +364,13 @@ describe('Exchange wrappers', () => {
             expect(initialOwnerTakerAsset).to.be.bignumber.equal(takerAddress);
             // Call Exchange
             const takerAssetFillAmount = signedOrder.takerAssetAmount;
-            await exchangeWrapper.fillOrderNoThrowAsync(signedOrder, takerAddress, { takerAssetFillAmount });
+            await exchangeWrapper.fillOrderNoThrowAsync(signedOrder, takerAddress, {
+                takerAssetFillAmount,
+                // HACK(albrow): We need to hardcode the gas estimate here because
+                // the Geth gas estimator doesn't work with the way we use
+                // delegatecall and swallow errors.
+                gas: 270000,
+            });
             // Verify post-conditions
             const newOwnerMakerAsset = await erc721Token.ownerOf.callAsync(makerAssetId);
             expect(newOwnerMakerAsset).to.be.bignumber.equal(takerAddress);
@@ -485,11 +495,11 @@ describe('Exchange wrappers', () => {
 
                 await exchangeWrapper.fillOrKillOrderAsync(signedOrders[0], takerAddress);
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     exchangeWrapper.batchFillOrKillOrdersAsync(signedOrders, takerAddress, {
                         takerAssetFillAmounts,
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
@@ -535,6 +545,10 @@ describe('Exchange wrappers', () => {
 
                 await exchangeWrapper.batchFillOrdersNoThrowAsync(signedOrders, takerAddress, {
                     takerAssetFillAmounts,
+                    // HACK(albrow): We need to hardcode the gas estimate here because
+                    // the Geth gas estimator doesn't work with the way we use
+                    // delegatecall and swallow errors.
+                    gas: 600000,
                 });
 
                 const newBalances = await erc20Wrapper.getBalancesAsync();
@@ -591,6 +605,10 @@ describe('Exchange wrappers', () => {
                 const newOrders = [invalidOrder, ...validOrders];
                 await exchangeWrapper.batchFillOrdersNoThrowAsync(newOrders, takerAddress, {
                     takerAssetFillAmounts,
+                    // HACK(albrow): We need to hardcode the gas estimate here because
+                    // the Geth gas estimator doesn't work with the way we use
+                    // delegatecall and swallow errors.
+                    gas: 450000,
                 });
 
                 const newBalances = await erc20Wrapper.getBalancesAsync();
@@ -679,11 +697,11 @@ describe('Exchange wrappers', () => {
                     orderFactory.newSignedOrder(),
                 ];
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     exchangeWrapper.marketSellOrdersAsync(signedOrders, takerAddress, {
                         takerAssetFillAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(1000), 18),
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
@@ -753,6 +771,10 @@ describe('Exchange wrappers', () => {
                 });
                 await exchangeWrapper.marketSellOrdersNoThrowAsync(signedOrders, takerAddress, {
                     takerAssetFillAmount,
+                    // HACK(albrow): We need to hardcode the gas estimate here because
+                    // the Geth gas estimator doesn't work with the way we use
+                    // delegatecall and swallow errors.
+                    gas: 600000,
                 });
 
                 const newBalances = await erc20Wrapper.getBalancesAsync();
@@ -768,11 +790,11 @@ describe('Exchange wrappers', () => {
                     orderFactory.newSignedOrder(),
                 ];
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     exchangeWrapper.marketSellOrdersNoThrowAsync(signedOrders, takerAddress, {
                         takerAssetFillAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(1000), 18),
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
@@ -857,11 +879,11 @@ describe('Exchange wrappers', () => {
                     orderFactory.newSignedOrder(),
                 ];
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     exchangeWrapper.marketBuyOrdersAsync(signedOrders, takerAddress, {
                         makerAssetFillAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(1000), 18),
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
@@ -931,6 +953,10 @@ describe('Exchange wrappers', () => {
                 });
                 await exchangeWrapper.marketSellOrdersNoThrowAsync(signedOrders, takerAddress, {
                     takerAssetFillAmount,
+                    // HACK(albrow): We need to hardcode the gas estimate here because
+                    // the Geth gas estimator doesn't work with the way we use
+                    // delegatecall and swallow errors.
+                    gas: 600000,
                 });
 
                 const newBalances = await erc20Wrapper.getBalancesAsync();
@@ -946,11 +972,11 @@ describe('Exchange wrappers', () => {
                     orderFactory.newSignedOrder(),
                 ];
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     exchangeWrapper.marketBuyOrdersNoThrowAsync(signedOrders, takerAddress, {
                         makerAssetFillAmount: Web3Wrapper.toBaseUnitAmount(new BigNumber(1000), 18),
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
diff --git a/packages/contracts/test/libraries/lib_bytes.ts b/packages/contracts/test/libraries/lib_bytes.ts
index 26cfa8291..dea45049e 100644
--- a/packages/contracts/test/libraries/lib_bytes.ts
+++ b/packages/contracts/test/libraries/lib_bytes.ts
@@ -1,15 +1,12 @@
-import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils';
-import { AssetProxyId } from '@0xproject/types';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { BigNumber } from '@0xproject/utils';
-import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import BN = require('bn.js');
 import * as chai from 'chai';
-import { LogWithDecodedArgs, TransactionReceiptWithDecodedLogs } from 'ethereum-types';
 import ethUtil = require('ethereumjs-util');
-import * as Web3 from 'web3';
 
 import { TestLibBytesContract } from '../../src/contract_wrappers/generated/test_lib_bytes';
 import { artifacts } from '../../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync, expectRevertOrOtherErrorAsync } from '../../src/utils/assertions';
 import { chaiSetup } from '../../src/utils/chai_setup';
 import { constants } from '../../src/utils/constants';
 import { provider, txDefaults, web3Wrapper } from '../../src/utils/web3_wrapper';
@@ -19,7 +16,6 @@ const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
 
 describe('LibBytes', () => {
-    let owner: string;
     let libBytes: TestLibBytesContract;
     const byteArrayShorterThan32Bytes = '0x012345';
     const byteArrayShorterThan20Bytes = byteArrayShorterThan32Bytes;
@@ -42,7 +38,6 @@ describe('LibBytes', () => {
     before(async () => {
         // Setup accounts & addresses
         const accounts = await web3Wrapper.getAvailableAddressesAsync();
-        owner = accounts[0];
         testAddress = accounts[1];
         // Deploy LibBytes
         libBytes = await TestLibBytesContract.deployFrom0xArtifactAsync(artifacts.TestLibBytes, provider, txDefaults);
@@ -63,7 +58,10 @@ describe('LibBytes', () => {
 
     describe('popByte', () => {
         it('should revert if length is 0', async () => {
-            return expect(libBytes.publicPopByte.callAsync(constants.NULL_BYTES)).to.be.rejectedWith(constants.REVERT);
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicPopByte.callAsync(constants.NULL_BYTES),
+                constants.LIB_BYTES_GT_ZERO_LENGTH_REQUIRED,
+            );
         });
 
         it('should pop the last byte from the input and return it', async () => {
@@ -77,8 +75,9 @@ describe('LibBytes', () => {
 
     describe('popAddress', () => {
         it('should revert if length is less than 20', async () => {
-            return expect(libBytes.publicPopAddress.callAsync(byteArrayShorterThan20Bytes)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicPopAddress.callAsync(byteArrayShorterThan20Bytes),
+                constants.LIB_BYTES_GTE_20_LENGTH_REQUIRED,
             );
         });
 
@@ -162,16 +161,18 @@ describe('LibBytes', () => {
         it('should fail if the byte array is too short to hold an address)', async () => {
             const shortByteArray = '0xabcdef';
             const offset = new BigNumber(0);
-            return expect(libBytes.publicReadAddress.callAsync(shortByteArray, offset)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicReadAddress.callAsync(shortByteArray, offset),
+                constants.LIB_BYTES_GTE_20_LENGTH_REQUIRED,
             );
         });
 
         it('should fail if the length between the offset and end of the byte array is too short to hold an address)', async () => {
             const byteArray = ethUtil.addHexPrefix(testAddress);
             const badOffset = new BigNumber(ethUtil.toBuffer(byteArray).byteLength);
-            return expect(libBytes.publicReadAddress.callAsync(byteArray, badOffset)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicReadAddress.callAsync(byteArray, badOffset),
+                constants.LIB_BYTES_GTE_20_LENGTH_REQUIRED,
             );
         });
     });
@@ -206,15 +207,17 @@ describe('LibBytes', () => {
 
         it('should fail if the byte array is too short to hold a bytes32)', async () => {
             const offset = new BigNumber(0);
-            return expect(libBytes.publicReadBytes32.callAsync(byteArrayShorterThan32Bytes, offset)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicReadBytes32.callAsync(byteArrayShorterThan32Bytes, offset),
+                constants.LIB_BYTES_GTE_32_LENGTH_REQUIRED,
             );
         });
 
         it('should fail if the length between the offset and end of the byte array is too short to hold a bytes32)', async () => {
             const badOffset = new BigNumber(ethUtil.toBuffer(testBytes32).byteLength);
-            return expect(libBytes.publicReadBytes32.callAsync(testBytes32, badOffset)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicReadBytes32.callAsync(testBytes32, badOffset),
+                constants.LIB_BYTES_GTE_32_LENGTH_REQUIRED,
             );
         });
     });
@@ -253,8 +256,9 @@ describe('LibBytes', () => {
 
         it('should fail if the byte array is too short to hold a uint256)', async () => {
             const offset = new BigNumber(0);
-            return expect(libBytes.publicReadUint256.callAsync(byteArrayShorterThan32Bytes, offset)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicReadUint256.callAsync(byteArrayShorterThan32Bytes, offset),
+                constants.LIB_BYTES_GTE_32_LENGTH_REQUIRED,
             );
         });
 
@@ -263,8 +267,9 @@ describe('LibBytes', () => {
             const testUint256AsBuffer = ethUtil.toBuffer(formattedTestUint256);
             const byteArray = ethUtil.bufferToHex(testUint256AsBuffer);
             const badOffset = new BigNumber(testUint256AsBuffer.byteLength);
-            return expect(libBytes.publicReadUint256.callAsync(byteArray, badOffset)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicReadUint256.callAsync(byteArray, badOffset),
+                constants.LIB_BYTES_GTE_32_LENGTH_REQUIRED,
             );
         });
     });
@@ -281,10 +286,12 @@ describe('LibBytes', () => {
     */
 
     describe('readFirst4', () => {
+        // AssertionError: expected promise to be rejected with an error including 'revert' but it was fulfilled with '0x08c379a0'
         it('should revert if byte array has a length < 4', async () => {
             const byteArrayLessThan4Bytes = '0x010101';
-            return expect(libBytes.publicReadFirst4.callAsync(byteArrayLessThan4Bytes)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                libBytes.publicReadFirst4.callAsync(byteArrayLessThan4Bytes),
+                constants.LIB_BYTES_GTE_4_LENGTH_REQUIRED,
             );
         });
         it('should return the first 4 bytes of a byte array of arbitrary length', async () => {
diff --git a/packages/contracts/test/multi_sig_with_time_lock.ts b/packages/contracts/test/multi_sig_with_time_lock.ts
index 1302d0fa0..48bc9b4e0 100644
--- a/packages/contracts/test/multi_sig_with_time_lock.ts
+++ b/packages/contracts/test/multi_sig_with_time_lock.ts
@@ -1,26 +1,25 @@
-import { BlockchainLifecycle, web3Factory } from '@0xproject/dev-utils';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { BigNumber } from '@0xproject/utils';
-import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
 import { LogWithDecodedArgs } from 'ethereum-types';
-import * as _ from 'lodash';
 import 'make-promises-safe';
-import * as Web3 from 'web3';
 
 import {
     MultiSigWalletWithTimeLockContract,
     SubmissionContractEventArgs,
 } from '../src/contract_wrappers/generated/multi_sig_wallet_with_time_lock';
 import { artifacts } from '../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../src/utils/assertions';
 import { chaiSetup } from '../src/utils/chai_setup';
 import { constants } from '../src/utils/constants';
+import { increaseTimeAndMineBlockAsync } from '../src/utils/increase_time';
 import { MultiSigWrapper } from '../src/utils/multi_sig_wrapper';
 import { provider, txDefaults, web3Wrapper } from '../src/utils/web3_wrapper';
 
 chaiSetup.configure();
 const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(web3Wrapper);
-
+// tslint:disable:no-unnecessary-type-assertion
 describe('MultiSigWalletWithTimeLock', () => {
     let owners: string[];
     const REQUIRED_APPROVALS = new BigNumber(2);
@@ -69,9 +68,9 @@ describe('MultiSigWalletWithTimeLock', () => {
             });
 
             it('should throw when not called by wallet', async () => {
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     multiSig.changeTimeLock.sendTransactionAsync(SECONDS_TIME_LOCKED, { from: owners[0] }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw without enough confirmations', async () => {
@@ -80,10 +79,9 @@ describe('MultiSigWalletWithTimeLock', () => {
                 const res = await multiSigWrapper.submitTransactionAsync(destination, changeTimeLockData, owners[0]);
                 const log = res.logs[0] as LogWithDecodedArgs<SubmissionContractEventArgs>;
                 const txId = log.args.transactionId;
-
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     multiSig.executeTransaction.sendTransactionAsync(txId, { from: owners[0] }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should set confirmation time with enough confirmations', async () => {
@@ -148,14 +146,15 @@ describe('MultiSigWalletWithTimeLock', () => {
                 txId = log.args.transactionId;
                 await multiSigWrapper.confirmTransactionAsync(txId, owners[1]);
             });
+
             it('should throw if it has enough confirmations but is not past the time lock', async () => {
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     multiSig.executeTransaction.sendTransactionAsync(txId, { from: owners[0] }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should execute if it has enough confirmations and is past the time lock', async () => {
-                await web3Wrapper.increaseTimeAsync(SECONDS_TIME_LOCKED.toNumber());
+                await increaseTimeAndMineBlockAsync(SECONDS_TIME_LOCKED.toNumber());
                 await web3Wrapper.awaitTransactionSuccessAsync(
                     await multiSig.executeTransaction.sendTransactionAsync(txId, { from: owners[0] }),
                     constants.AWAIT_TRANSACTION_MINED_MS,
@@ -167,3 +166,4 @@ describe('MultiSigWalletWithTimeLock', () => {
         });
     });
 });
+// tslint:enable:no-unnecessary-type-assertion
diff --git a/packages/contracts/test/token_registry.ts b/packages/contracts/test/token_registry.ts
index 64caac387..9526c9dcf 100644
--- a/packages/contracts/test/token_registry.ts
+++ b/packages/contracts/test/token_registry.ts
@@ -1,14 +1,13 @@
-import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { BigNumber, NULL_BYTES } from '@0xproject/utils';
-import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
 import ethUtil = require('ethereumjs-util');
 import * as _ from 'lodash';
 import 'make-promises-safe';
-import * as Web3 from 'web3';
 
 import { TokenRegistryContract } from '../src/contract_wrappers/generated/token_registry';
 import { artifacts } from '../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync } from '../src/utils/assertions';
 import { chaiSetup } from '../src/utils/chai_setup';
 import { constants } from '../src/utils/constants';
 import { TokenRegWrapper } from '../src/utils/token_registry_wrapper';
@@ -76,7 +75,7 @@ describe('TokenRegistry', () => {
 
     describe('addToken', () => {
         it('should throw when not called by owner', async () => {
-            return expect(tokenRegWrapper.addTokenAsync(token1, notOwner)).to.be.rejectedWith(constants.REVERT);
+            return expectRevertOrAlwaysFailingTransactionAsync(tokenRegWrapper.addTokenAsync(token1, notOwner));
         });
 
         it('should add token metadata when called by owner', async () => {
@@ -88,19 +87,19 @@ describe('TokenRegistry', () => {
         it('should throw if token already exists', async () => {
             await tokenRegWrapper.addTokenAsync(token1, owner);
 
-            return expect(tokenRegWrapper.addTokenAsync(token1, owner)).to.be.rejectedWith(constants.REVERT);
+            return expectRevertOrAlwaysFailingTransactionAsync(tokenRegWrapper.addTokenAsync(token1, owner));
         });
 
         it('should throw if token address is null', async () => {
-            return expect(tokenRegWrapper.addTokenAsync(nullToken, owner)).to.be.rejectedWith(constants.REVERT);
+            return expectRevertOrAlwaysFailingTransactionAsync(tokenRegWrapper.addTokenAsync(nullToken, owner));
         });
 
         it('should throw if name already exists', async () => {
             await tokenRegWrapper.addTokenAsync(token1, owner);
             const duplicateNameToken = _.assign({}, token2, { name: token1.name });
 
-            return expect(tokenRegWrapper.addTokenAsync(duplicateNameToken, owner)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                tokenRegWrapper.addTokenAsync(duplicateNameToken, owner),
             );
         });
 
@@ -110,8 +109,8 @@ describe('TokenRegistry', () => {
                 symbol: token1.symbol,
             });
 
-            return expect(tokenRegWrapper.addTokenAsync(duplicateSymbolToken, owner)).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrAlwaysFailingTransactionAsync(
+                tokenRegWrapper.addTokenAsync(duplicateSymbolToken, owner),
             );
         });
     });
@@ -137,9 +136,9 @@ describe('TokenRegistry', () => {
 
         describe('setTokenName', () => {
             it('should throw when not called by owner', async () => {
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.setTokenName.sendTransactionAsync(token1.address, token2.name, { from: notOwner }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should change the token name when called by owner', async () => {
@@ -163,25 +162,25 @@ describe('TokenRegistry', () => {
             it('should throw if the name already exists', async () => {
                 await tokenRegWrapper.addTokenAsync(token2, owner);
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.setTokenName.sendTransactionAsync(token1.address, token2.name, { from: owner }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw if token does not exist', async () => {
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.setTokenName.sendTransactionAsync(nullToken.address, token2.name, { from: owner }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
         describe('setTokenSymbol', () => {
             it('should throw when not called by owner', async () => {
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.setTokenSymbol.sendTransactionAsync(token1.address, token2.symbol, {
                         from: notOwner,
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should change the token symbol when called by owner', async () => {
@@ -203,28 +202,28 @@ describe('TokenRegistry', () => {
             it('should throw if the symbol already exists', async () => {
                 await tokenRegWrapper.addTokenAsync(token2, owner);
 
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.setTokenSymbol.sendTransactionAsync(token1.address, token2.symbol, {
                         from: owner,
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw if token does not exist', async () => {
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.setTokenSymbol.sendTransactionAsync(nullToken.address, token2.symbol, {
                         from: owner,
                     }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
 
         describe('removeToken', () => {
             it('should throw if not called by owner', async () => {
                 const index = new BigNumber(0);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.removeToken.sendTransactionAsync(token1.address, index, { from: notOwner }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should remove token metadata when called by owner', async () => {
@@ -241,17 +240,17 @@ describe('TokenRegistry', () => {
 
             it('should throw if token does not exist', async () => {
                 const index = new BigNumber(0);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.removeToken.sendTransactionAsync(nullToken.address, index, { from: owner }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
 
             it('should throw if token at given index does not match address', async () => {
                 await tokenRegWrapper.addTokenAsync(token2, owner);
                 const incorrectIndex = new BigNumber(0);
-                return expect(
+                return expectRevertOrAlwaysFailingTransactionAsync(
                     tokenReg.removeToken.sendTransactionAsync(token2.address, incorrectIndex, { from: owner }),
-                ).to.be.rejectedWith(constants.REVERT);
+                );
             });
         });
     });
diff --git a/packages/contracts/test/unlimited_allowance_token.ts b/packages/contracts/test/unlimited_allowance_token.ts
index b2acdebaa..ac232d8ff 100644
--- a/packages/contracts/test/unlimited_allowance_token.ts
+++ b/packages/contracts/test/unlimited_allowance_token.ts
@@ -1,12 +1,11 @@
-import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { BigNumber } from '@0xproject/utils';
-import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
 import 'make-promises-safe';
-import * as Web3 from 'web3';
 
 import { DummyERC20TokenContract } from '../src/contract_wrappers/generated/dummy_e_r_c20_token';
 import { artifacts } from '../src/utils/artifacts';
+import { expectRevertOrAlwaysFailingTransactionAsync, expectRevertOrOtherErrorAsync } from '../src/utils/assertions';
 import { chaiSetup } from '../src/utils/chai_setup';
 import { constants } from '../src/utils/constants';
 import { provider, txDefaults, web3Wrapper } from '../src/utils/web3_wrapper';
@@ -55,8 +54,9 @@ describe('UnlimitedAllowanceToken', () => {
         it('should throw if owner has insufficient balance', async () => {
             const ownerBalance = await token.balanceOf.callAsync(owner);
             const amountToTransfer = ownerBalance.plus(1);
-            return expect(token.transfer.callAsync(spender, amountToTransfer, { from: owner })).to.be.rejectedWith(
-                constants.REVERT,
+            return expectRevertOrOtherErrorAsync(
+                token.transfer.callAsync(spender, amountToTransfer, { from: owner }),
+                constants.ERC20_INSUFFICIENT_BALANCE,
             );
         });
 
@@ -93,11 +93,12 @@ describe('UnlimitedAllowanceToken', () => {
                 await token.approve.sendTransactionAsync(spender, amountToTransfer, { from: owner }),
                 constants.AWAIT_TRANSACTION_MINED_MS,
             );
-            return expect(
+            return expectRevertOrOtherErrorAsync(
                 token.transferFrom.callAsync(owner, spender, amountToTransfer, {
                     from: spender,
                 }),
-            ).to.be.rejectedWith(constants.REVERT);
+                constants.ERC20_INSUFFICIENT_BALANCE,
+            );
         });
 
         it('should throw if spender has insufficient allowance', async () => {
@@ -108,11 +109,12 @@ describe('UnlimitedAllowanceToken', () => {
             const isSpenderAllowanceInsufficient = spenderAllowance.cmp(amountToTransfer) < 0;
             expect(isSpenderAllowanceInsufficient).to.be.true();
 
-            return expect(
+            return expectRevertOrOtherErrorAsync(
                 token.transferFrom.callAsync(owner, spender, amountToTransfer, {
                     from: spender,
                 }),
-            ).to.be.rejectedWith(constants.REVERT);
+                constants.ERC20_INSUFFICIENT_ALLOWANCE,
+            );
         });
 
         it('should return true on a 0 value transfer', async () => {
diff --git a/packages/contracts/test/zrx_token.ts b/packages/contracts/test/zrx_token.ts
index fe37e802b..0dbafce69 100644
--- a/packages/contracts/test/zrx_token.ts
+++ b/packages/contracts/test/zrx_token.ts
@@ -1,9 +1,8 @@
-import { BlockchainLifecycle, devConstants, web3Factory } from '@0xproject/dev-utils';
+import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as chai from 'chai';
 import 'make-promises-safe';
-import * as Web3 from 'web3';
 
 import { ZRXTokenContract } from '../src/contract_wrappers/generated/zrx_token';
 import { artifacts } from '../src/utils/artifacts';