Merge pull request #205 from 0xProject/orderWatcher

Order watcher

8 files changed, 530 insertions, 22 deletions

diff --git a/test/event_watcher_test.ts b/test/event_watcher_test.ts
new file mode 100644
index 000000000..b4164fe63
--- /dev/null
+++ b/test/event_watcher_test.ts
@@ -0,0 +1,127 @@
+import 'mocha';
+import * as chai from 'chai';
+import * as _ from 'lodash';
+import * as Sinon from 'sinon';
+import * as Web3 from 'web3';
+import BigNumber from 'bignumber.js';
+import {chaiSetup} from './utils/chai_setup';
+import {web3Factory} from './utils/web3_factory';
+import {Web3Wrapper} from '../src/web3_wrapper';
+import {EventWatcher} from '../src/order_watcher/event_watcher';
+import {
+    ZeroEx,
+    LogEvent,
+    DecodedLogEvent,
+} from '../src';
+import {DoneCallback} from '../src/types';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('EventWatcher', () => {
+    let web3: Web3;
+    let stubs: Sinon.SinonStub[] = [];
+    let eventWatcher: EventWatcher;
+    let web3Wrapper: Web3Wrapper;
+    const numConfirmations = 0;
+    const logA: Web3.LogEntry = {
+        address: '0x71d271f8b14adef568f8f28f1587ce7271ac4ca5',
+        blockHash: null,
+        blockNumber: null,
+        data: '',
+        logIndex: null,
+        topics: [],
+        transactionHash: '0x004881d38cd4a8f72f1a0d68c8b9b8124504706041ff37019c1d1ed6bfda8e17',
+        transactionIndex: 0,
+    };
+    const logB: Web3.LogEntry = {
+        address: '0x8d12a197cb00d4747a1fe03395095ce2a5cc6819',
+        blockHash: null,
+        blockNumber: null,
+        data: '',
+        logIndex: null,
+        topics: [ '0xf341246adaac6f497bc2a656f546ab9e182111d630394f0c57c710a59a2cb567' ],
+        transactionHash: '0x01ef3c048b18d9b09ea195b4ed94cf8dd5f3d857a1905ff886b152cfb1166f25',
+        transactionIndex: 0,
+    };
+    const logC: Web3.LogEntry = {
+        address: '0x1d271f8b174adef58f1587ce68f8f27271ac4ca5',
+        blockHash: null,
+        blockNumber: null,
+        data: '',
+        logIndex: null,
+        topics: [ '0xf341246adaac6f497bc2a656f546ab9e182111d630394f0c57c710a59a2cb567' ],
+        transactionHash: '0x01ef3c048b18d9b09ea195b4ed94cf8dd5f3d857a1905ff886b152cfb1166f25',
+        transactionIndex: 0,
+    };
+    before(async () => {
+        web3 = web3Factory.create();
+        const pollingIntervalMs = 10;
+        web3Wrapper = new Web3Wrapper(web3.currentProvider);
+        eventWatcher = new EventWatcher(web3Wrapper, pollingIntervalMs);
+    });
+    afterEach(() => {
+        // clean up any stubs after the test has completed
+        _.each(stubs, s => s.restore());
+        stubs = [];
+        eventWatcher.unsubscribe();
+    });
+    it('correctly emits initial log events', (done: DoneCallback) => {
+        const logs: Web3.LogEntry[] = [logA, logB];
+        const expectedLogEvents = [
+            {
+                removed: false,
+                ...logA,
+            },
+            {
+                removed: false,
+                ...logB,
+            },
+        ];
+        const getLogsStub = Sinon.stub(web3Wrapper, 'getLogsAsync');
+        getLogsStub.onCall(0).returns(logs);
+        stubs.push(getLogsStub);
+        const callback = (event: LogEvent) => {
+            const expectedLogEvent = expectedLogEvents.shift();
+            expect(event).to.be.deep.equal(expectedLogEvent);
+            if (_.isEmpty(expectedLogEvents)) {
+                done();
+            }
+        };
+        eventWatcher.subscribe(callback);
+    });
+    it('correctly computes the difference and emits only changes', (done: DoneCallback) => {
+        const initialLogs: Web3.LogEntry[] = [logA, logB];
+        const changedLogs: Web3.LogEntry[] = [logA, logC];
+        const expectedLogEvents = [
+            {
+                removed: false,
+                ...logA,
+            },
+            {
+                removed: false,
+                ...logB,
+            },
+            {
+                removed: true,
+                ...logB,
+            },
+            {
+                removed: false,
+                ...logC,
+            },
+        ];
+        const getLogsStub = Sinon.stub(web3Wrapper, 'getLogsAsync');
+        getLogsStub.onCall(0).returns(initialLogs);
+        getLogsStub.onCall(1).returns(changedLogs);
+        stubs.push(getLogsStub);
+        const callback = (event: LogEvent) => {
+            const expectedLogEvent = expectedLogEvents.shift();
+            expect(event).to.be.deep.equal(expectedLogEvent);
+            if (_.isEmpty(expectedLogEvents)) {
+                done();
+            }
+        };
+        eventWatcher.subscribe(callback);
+    });
+});
diff --git a/test/exchange_transfer_simulator_test.ts b/test/exchange_transfer_simulator_test.ts
index 3373ebf03..99cb7fb4f 100644
--- a/test/exchange_transfer_simulator_test.ts
+++ b/test/exchange_transfer_simulator_test.ts
@@ -59,11 +59,10 @@ describe('ExchangeTransferSimulator', () => {
             await exchangeTransferSimulator.transferFromAsync(
                 exampleTokenAddress, sender, recipient, transferAmount, TradeSide.Taker, TransferType.Trade,
             );
-            const senderBalance = await (exchangeTransferSimulator as any).getBalanceAsync(exampleTokenAddress, sender);
-            const recipientBalance = await (exchangeTransferSimulator as any).getBalanceAsync(
-                exampleTokenAddress, recipient);
-            const senderProxyAllowance = await (exchangeTransferSimulator as any).getProxyAllowanceAsync(
-                exampleTokenAddress, sender);
+            const store = (exchangeTransferSimulator as any).store;
+            const senderBalance = await store.getBalanceAsync(exampleTokenAddress, sender);
+            const recipientBalance = await store.getBalanceAsync(exampleTokenAddress, recipient);
+            const senderProxyAllowance = await store.getProxyAllowanceAsync(exampleTokenAddress, sender);
             expect(senderBalance).to.be.bignumber.equal(0);
             expect(recipientBalance).to.be.bignumber.equal(transferAmount);
             expect(senderProxyAllowance).to.be.bignumber.equal(0);
@@ -76,11 +75,10 @@ describe('ExchangeTransferSimulator', () => {
             await exchangeTransferSimulator.transferFromAsync(
                 exampleTokenAddress, sender, recipient, transferAmount, TradeSide.Taker, TransferType.Trade,
             );
-            const senderBalance = await (exchangeTransferSimulator as any).getBalanceAsync(exampleTokenAddress, sender);
-            const recipientBalance = await (exchangeTransferSimulator as any).getBalanceAsync(
-                exampleTokenAddress, recipient);
-            const senderProxyAllowance = await (exchangeTransferSimulator as any).getProxyAllowanceAsync(
-                exampleTokenAddress, sender);
+            const store = (exchangeTransferSimulator as any).store;
+            const senderBalance = await store.getBalanceAsync(exampleTokenAddress, sender);
+            const recipientBalance = await store.getBalanceAsync(exampleTokenAddress, recipient);
+            const senderProxyAllowance = await store.getProxyAllowanceAsync(exampleTokenAddress, sender);
             expect(senderBalance).to.be.bignumber.equal(0);
             expect(recipientBalance).to.be.bignumber.equal(transferAmount);
             expect(senderProxyAllowance).to.be.bignumber.equal(zeroEx.token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
diff --git a/test/exchange_wrapper_test.ts b/test/exchange_wrapper_test.ts
index 654f626c6..26b8c1e0e 100644
--- a/test/exchange_wrapper_test.ts
+++ b/test/exchange_wrapper_test.ts
@@ -11,13 +11,13 @@ import {
     SignedOrder,
     SubscriptionOpts,
     ExchangeEvents,
-    ContractEvent,
     ExchangeContractErrs,
     OrderCancellationRequest,
     OrderFillRequest,
     LogFillContractEventArgs,
     LogCancelContractEventArgs,
     LogEvent,
+    DecodedLogEvent,
 } from '../src';
 import {DoneCallback, BlockParamLiteral} from '../src/types';
 import {FillScenarios} from './utils/fill_scenarios';
@@ -70,7 +70,7 @@ describe('ExchangeWrapper', () => {
             takerTokenAddress = takerToken.address;
         });
         describe('#batchFillOrKillAsync', () => {
-            it('successfuly batch fillOrKill', async () => {
+            it('successfully batch fillOrKill', async () => {
                 const fillableAmount = new BigNumber(5);
                 const partialFillTakerAmount = new BigNumber(2);
                 const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
@@ -647,7 +647,8 @@ describe('ExchangeWrapper', () => {
         // Source: https://github.com/mochajs/mocha/issues/2407
         it('Should receive the LogFill event when an order is filled', (done: DoneCallback) => {
             (async () => {
-                const callback = (err: Error, logEvent: LogEvent<LogFillContractEventArgs>) => {
+
+                const callback = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
                     expect(logEvent.event).to.be.equal(ExchangeEvents.LogFill);
                     done();
                 };
@@ -662,7 +663,8 @@ describe('ExchangeWrapper', () => {
         });
         it('Should receive the LogCancel event when an order is cancelled', (done: DoneCallback) => {
             (async () => {
-                const callback = (err: Error, logEvent: LogEvent<LogCancelContractEventArgs>) => {
+
+                const callback = (err: Error, logEvent: DecodedLogEvent<LogCancelContractEventArgs>) => {
                     expect(logEvent.event).to.be.equal(ExchangeEvents.LogCancel);
                     done();
                 };
@@ -674,7 +676,8 @@ describe('ExchangeWrapper', () => {
         });
         it('Outstanding subscriptions are cancelled when zeroEx.setProviderAsync called', (done: DoneCallback) => {
             (async () => {
-                const callbackNeverToBeCalled = (err: Error, logEvent: LogEvent<LogFillContractEventArgs>) => {
+
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
                     done(new Error('Expected this subscription to have been cancelled'));
                 };
                 await zeroEx.exchange.subscribeAsync(
@@ -684,7 +687,7 @@ describe('ExchangeWrapper', () => {
                 const newProvider = web3Factory.getRpcProvider();
                 await zeroEx.setProviderAsync(newProvider);
 
-                const callback = (err: Error, logEvent: LogEvent<LogFillContractEventArgs>) => {
+                const callback = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
                     expect(logEvent.event).to.be.equal(ExchangeEvents.LogFill);
                     done();
                 };
@@ -699,7 +702,7 @@ describe('ExchangeWrapper', () => {
         });
         it('Should cancel subscription when unsubscribe called', (done: DoneCallback) => {
             (async () => {
-                const callbackNeverToBeCalled = (err: Error, logEvent: LogEvent<LogFillContractEventArgs>) => {
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
                     done(new Error('Expected this subscription to have been cancelled'));
                 };
                 const subscriptionToken = await zeroEx.exchange.subscribeAsync(
diff --git a/test/order_state_watcher_test.ts b/test/order_state_watcher_test.ts
new file mode 100644
index 000000000..c8a4a8064
--- /dev/null
+++ b/test/order_state_watcher_test.ts
@@ -0,0 +1,356 @@
+import 'mocha';
+import * as chai from 'chai';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+import BigNumber from 'bignumber.js';
+import { chaiSetup } from './utils/chai_setup';
+import { web3Factory } from './utils/web3_factory';
+import { Web3Wrapper } from '../src/web3_wrapper';
+import { OrderStateWatcher } from '../src/order_watcher/order_state_watcher';
+import {
+    Token,
+    ZeroEx,
+    LogEvent,
+    DecodedLogEvent,
+    ZeroExConfig,
+    OrderState,
+    SignedOrder,
+    ZeroExError,
+    OrderStateValid,
+    OrderStateInvalid,
+    ExchangeContractErrs,
+} from '../src';
+import { TokenUtils } from './utils/token_utils';
+import { FillScenarios } from './utils/fill_scenarios';
+import { DoneCallback } from '../src/types';
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {reportCallbackErrors} from './utils/report_callback_errors';
+
+const TIMEOUT_MS = 150;
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle();
+
+describe('OrderStateWatcher', () => {
+    let web3: Web3;
+    let zeroEx: ZeroEx;
+    let tokens: Token[];
+    let tokenUtils: TokenUtils;
+    let fillScenarios: FillScenarios;
+    let userAddresses: string[];
+    let zrxTokenAddress: string;
+    let exchangeContractAddress: string;
+    let makerToken: Token;
+    let takerToken: Token;
+    let maker: string;
+    let taker: string;
+    let web3Wrapper: Web3Wrapper;
+    let signedOrder: SignedOrder;
+    const fillableAmount = new BigNumber(5);
+    before(async () => {
+        web3 = web3Factory.create();
+        zeroEx = new ZeroEx(web3.currentProvider);
+        exchangeContractAddress = await zeroEx.exchange.getContractAddressAsync();
+        userAddresses = await zeroEx.getAvailableAddressesAsync();
+        [, maker, taker] = userAddresses;
+        tokens = await zeroEx.tokenRegistry.getTokensAsync();
+        tokenUtils = new TokenUtils(tokens);
+        zrxTokenAddress = tokenUtils.getProtocolTokenOrThrow().address;
+        fillScenarios = new FillScenarios(zeroEx, userAddresses, tokens, zrxTokenAddress, exchangeContractAddress);
+        [makerToken, takerToken] = tokenUtils.getNonProtocolTokens();
+        web3Wrapper = (zeroEx as any)._web3Wrapper;
+    });
+    describe('#removeOrder', async () => {
+        it('should successfully remove existing order', async () => {
+            signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerToken.address, takerToken.address, maker, taker, fillableAmount,
+            );
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            zeroEx.orderStateWatcher.addOrder(signedOrder);
+            expect((zeroEx.orderStateWatcher as any)._orderByOrderHash).to.include({
+                [orderHash]: signedOrder,
+            });
+            let dependentOrderHashes = (zeroEx.orderStateWatcher as any)._dependentOrderHashes;
+            expect(dependentOrderHashes[signedOrder.maker][signedOrder.makerTokenAddress]).to.have.keys(orderHash);
+            zeroEx.orderStateWatcher.removeOrder(orderHash);
+            expect((zeroEx.orderStateWatcher as any)._orderByOrderHash).to.not.include({
+                [orderHash]: signedOrder,
+            });
+            dependentOrderHashes = (zeroEx.orderStateWatcher as any)._dependentOrderHashes;
+            expect(dependentOrderHashes[signedOrder.maker]).to.be.undefined();
+        });
+        it('should no-op when removing a non-existing order', async () => {
+            signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerToken.address, takerToken.address, maker, taker, fillableAmount,
+            );
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            const nonExistentOrderHash = `0x${orderHash.substr(2).split('').reverse().join('')}`;
+            zeroEx.orderStateWatcher.removeOrder(nonExistentOrderHash);
+        });
+    });
+    describe('#subscribe', async () => {
+        afterEach(async () => {
+            zeroEx.orderStateWatcher.unsubscribe();
+        });
+        it('should fail when trying to subscribe twice', async () => {
+            zeroEx.orderStateWatcher.subscribe(_.noop);
+            expect(() => zeroEx.orderStateWatcher.subscribe(_.noop))
+                .to.throw(ZeroExError.SubscriptionAlreadyPresent);
+        });
+    });
+    describe('tests with cleanup', async () => {
+        afterEach(async () => {
+            zeroEx.orderStateWatcher.unsubscribe();
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            zeroEx.orderStateWatcher.removeOrder(orderHash);
+        });
+        it('should emit orderStateInvalid when maker allowance set to 0 for watched order', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.InsufficientMakerAllowance);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                await zeroEx.token.setProxyAllowanceAsync(makerToken.address, maker, new BigNumber(0));
+            })().catch(done);
+        });
+        it('should not emit an orderState event when irrelevant Transfer event received', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    throw new Error('OrderState callback fired for irrelevant order');
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                const notTheMaker = userAddresses[0];
+                const anyRecipient = taker;
+                const transferAmount = new BigNumber(2);
+                const notTheMakerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, notTheMaker);
+                await zeroEx.token.transferAsync(makerToken.address, notTheMaker, anyRecipient, transferAmount);
+                setTimeout(() => {
+                    done();
+                }, TIMEOUT_MS);
+            })().catch(done);
+        });
+        it('should emit orderStateInvalid when maker moves balance backing watched order', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.InsufficientMakerBalance);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                const anyRecipient = taker;
+                const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                await zeroEx.token.transferAsync(makerToken.address, maker, anyRecipient, makerBalance);
+            })().catch(done);
+        });
+        it('should emit orderStateInvalid when watched order fully filled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                let eventCount = 0;
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    eventCount++;
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderRemainingFillAmountZero);
+                    if (eventCount === 2) {
+                        done();
+                    }
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+
+                const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                await zeroEx.exchange.fillOrderAsync(
+                    signedOrder, fillableAmount, shouldThrowOnInsufficientBalanceOrAllowance, taker,
+                );
+            })().catch(done);
+        });
+        it('should emit orderStateValid when watched order partially filled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+
+                const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                const takerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, taker);
+
+                const fillAmountInBaseUnits = new BigNumber(2);
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                let eventCount = 0;
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    eventCount++;
+                    expect(orderState.isValid).to.be.true();
+                    const validOrderState = orderState as OrderStateValid;
+                    expect(validOrderState.orderHash).to.be.equal(orderHash);
+                    const orderRelevantState = validOrderState.orderRelevantState;
+                    const remainingMakerBalance = makerBalance.sub(fillAmountInBaseUnits);
+                    const remainingFillable = fillableAmount.minus(fillAmountInBaseUnits);
+                    expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                        remainingFillable);
+                    expect(orderRelevantState.makerBalance).to.be.bignumber.equal(remainingMakerBalance);
+                    if (eventCount === 2) {
+                        done();
+                    }
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                await zeroEx.exchange.fillOrderAsync(
+                    signedOrder, fillAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, taker,
+                );
+            })().catch(done);
+        });
+        describe('remainingFillableMakerTokenAmount', () => {
+          it('should calculate correct remaining fillable', (done: DoneCallback) => {
+              (async () => {
+                  const takerFillableAmount = new BigNumber(10);
+                  const makerFillableAmount = new BigNumber(20);
+                  signedOrder = await fillScenarios.createAsymmetricFillableSignedOrderAsync(
+                      makerToken.address, takerToken.address, maker, taker, makerFillableAmount, takerFillableAmount);
+                  const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                  const takerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, taker);
+                  const fillAmountInBaseUnits = new BigNumber(2);
+                  const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                  zeroEx.orderStateWatcher.addOrder(signedOrder);
+                  let eventCount = 0;
+                  const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                      eventCount++;
+                      expect(orderState.isValid).to.be.true();
+                      const validOrderState = orderState as OrderStateValid;
+                      expect(validOrderState.orderHash).to.be.equal(orderHash);
+                      const orderRelevantState = validOrderState.orderRelevantState;
+                      expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                          new BigNumber(16));
+                      if (eventCount === 2) {
+                          done();
+                      }
+                  });
+                  zeroEx.orderStateWatcher.subscribe(callback);
+                  const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                  await zeroEx.exchange.fillOrderAsync(
+                      signedOrder, fillAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, taker,
+                  );
+              })().catch(done);
+          });
+          it('should equal approved amount when approved amount is lowest', (done: DoneCallback) => {
+              (async () => {
+                  signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                      makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                  );
+
+                  const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+
+                  const changedMakerApprovalAmount = new BigNumber(3);
+                  zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                  const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                      const validOrderState = orderState as OrderStateValid;
+                      const orderRelevantState = validOrderState.orderRelevantState;
+                      expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                          changedMakerApprovalAmount);
+                      done();
+                  });
+                  zeroEx.orderStateWatcher.subscribe(callback);
+                  await zeroEx.token.setProxyAllowanceAsync(makerToken.address, maker, changedMakerApprovalAmount);
+              })().catch(done);
+          });
+          it('should equal balance amount when balance amount is lowest', (done: DoneCallback) => {
+              (async () => {
+                  signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                      makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                  );
+
+                  const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+
+                  const remainingAmount = new BigNumber(1);
+                  const transferAmount = makerBalance.sub(remainingAmount);
+                  zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                  const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                      const validOrderState = orderState as OrderStateValid;
+                      const orderRelevantState = validOrderState.orderRelevantState;
+                      expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                          remainingAmount);
+                      done();
+                  });
+                  zeroEx.orderStateWatcher.subscribe(callback);
+                  await zeroEx.token.transferAsync(
+                      makerToken.address, maker, ZeroEx.NULL_ADDRESS, transferAmount);
+              })().catch(done);
+          });
+        });
+        it('should emit orderStateInvalid when watched order cancelled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderRemainingFillAmountZero);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+
+                const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                await zeroEx.exchange.cancelOrderAsync(signedOrder, fillableAmount);
+            })().catch(done);
+        });
+        it('should emit orderStateValid when watched order partially cancelled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+
+                const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                const takerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, taker);
+
+                const cancelAmountInBaseUnits = new BigNumber(2);
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.true();
+                    const validOrderState = orderState as OrderStateValid;
+                    expect(validOrderState.orderHash).to.be.equal(orderHash);
+                    const orderRelevantState = validOrderState.orderRelevantState;
+                    expect(orderRelevantState.canceledTakerTokenAmount).to.be.bignumber.equal(cancelAmountInBaseUnits);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                await zeroEx.exchange.cancelOrderAsync(signedOrder, cancelAmountInBaseUnits);
+            })().catch(done);
+        });
+    });
+});
diff --git a/test/token_wrapper_test.ts b/test/token_wrapper_test.ts
index d9d0fb9ad..40652d03c 100644
--- a/test/token_wrapper_test.ts
+++ b/test/token_wrapper_test.ts
@@ -17,6 +17,7 @@ import {
     TokenContractEventArgs,
     LogWithDecodedArgs,
     LogEvent,
+    DecodedLogEvent,
 } from '../src';
 import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
 import {TokenUtils} from './utils/token_utils';
@@ -358,7 +359,7 @@ describe('TokenWrapper', () => {
         // Source: https://github.com/mochajs/mocha/issues/2407
         it('Should receive the Transfer event when tokens are transfered', (done: DoneCallback) => {
             (async () => {
-                const callback = (err: Error, logEvent: LogEvent<TransferContractEventArgs>) => {
+                const callback = (err: Error, logEvent: DecodedLogEvent<TransferContractEventArgs>) => {
                     expect(logEvent).to.not.be.undefined();
                     const args = logEvent.args;
                     expect(args._from).to.be.equal(coinbase);
@@ -373,7 +374,7 @@ describe('TokenWrapper', () => {
         });
         it('Should receive the Approval event when allowance is being set', (done: DoneCallback) => {
             (async () => {
-                const callback = (err: Error, logEvent: LogEvent<ApprovalContractEventArgs>) => {
+                const callback = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
                     expect(logEvent).to.not.be.undefined();
                     const args = logEvent.args;
                     expect(args._owner).to.be.equal(coinbase);
@@ -388,13 +389,13 @@ describe('TokenWrapper', () => {
         });
         it('Outstanding subscriptions are cancelled when zeroEx.setProviderAsync called', (done: DoneCallback) => {
             (async () => {
-                const callbackNeverToBeCalled = (err: Error, logEvent: LogEvent<TransferContractEventArgs>) => {
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
                     done(new Error('Expected this subscription to have been cancelled'));
                 };
                 zeroEx.token.subscribe(
                     tokenAddress, TokenEvents.Transfer, indexFilterValues, callbackNeverToBeCalled,
                 );
-                const callbackToBeCalled = (err: Error, logEvent: LogEvent<TransferContractEventArgs>) => {
+                const callbackToBeCalled = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
                     done();
                 };
                 const newProvider = web3Factory.getRpcProvider();
@@ -407,7 +408,7 @@ describe('TokenWrapper', () => {
         });
         it('Should cancel subscription when unsubscribe called', (done: DoneCallback) => {
             (async () => {
-                const callbackNeverToBeCalled = (err: Error, logEvent: LogEvent<TokenContractEventArgs>) => {
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
                     done(new Error('Expected this subscription to have been cancelled'));
                 };
                 const subscriptionToken = zeroEx.token.subscribe(
diff --git a/test/utils/blockchain_lifecycle.ts b/test/utils/blockchain_lifecycle.ts
index 9fdf0e856..9a44ccd6f 100644
--- a/test/utils/blockchain_lifecycle.ts
+++ b/test/utils/blockchain_lifecycle.ts
@@ -20,4 +20,7 @@ export class BlockchainLifecycle {
             throw new Error(`Snapshot with id #${snapshotId} failed to revert`);
         }
     }
+    public async mineABlock(): Promise<void> {
+        await this.rpc.mineBlockAsync();
+    }
 }
diff --git a/test/utils/report_callback_errors.ts b/test/utils/report_callback_errors.ts
new file mode 100644
index 000000000..d471b2af2
--- /dev/null
+++ b/test/utils/report_callback_errors.ts
@@ -0,0 +1,14 @@
+import { DoneCallback } from '../../src/types';
+
+export const reportCallbackErrors = (done: DoneCallback) => {
+    return (f: (...args: any[]) => void) => {
+        const wrapped = (...args: any[]) => {
+            try {
+                f(...args);
+            } catch (err) {
+                done(err);
+            }
+        };
+        return wrapped;
+    };
+};
diff --git a/test/utils/rpc.ts b/test/utils/rpc.ts
index f28a85340..299e72e79 100644
--- a/test/utils/rpc.ts
+++ b/test/utils/rpc.ts
@@ -26,6 +26,12 @@ export class RPC {
         const didRevert = await this.sendAsync(payload);
         return didRevert;
     }
+    public async mineBlockAsync(): Promise<void> {
+        const method = 'evm_mine';
+        const params: any[] = [];
+        const payload = this.toPayload(method, params);
+        await this.sendAsync(payload);
+    }
     private toPayload(method: string, params: any[] = []): string {
         const payload = JSON.stringify({
             id: this.id,