Enable some new linter rules and fix the issues

11 files changed, 162 insertions, 159 deletions

diff --git a/packages/0x.js/src/contract_wrappers/exchange_wrapper.ts b/packages/0x.js/src/contract_wrappers/exchange_wrapper.ts
index 97ea54362..b35219b24 100644
--- a/packages/0x.js/src/contract_wrappers/exchange_wrapper.ts
+++ b/packages/0x.js/src/contract_wrappers/exchange_wrapper.ts
@@ -559,7 +559,7 @@ export class ExchangeWrapper extends ContractWrapper {
         if (shouldValidate) {
             const orderHash = utils.getOrderHashHex(order);
             const unavailableTakerTokenAmount = await this.getUnavailableTakerAmountAsync(orderHash);
-            this._orderValidationUtils.validateCancelOrderThrowIfInvalid(
+            OrderValidationUtils.validateCancelOrderThrowIfInvalid(
                 order, cancelTakerTokenAmount, unavailableTakerTokenAmount);
         }
 
@@ -613,7 +613,7 @@ export class ExchangeWrapper extends ContractWrapper {
             for (const orderCancellationRequest of orderCancellationRequests) {
                 const orderHash = utils.getOrderHashHex(orderCancellationRequest.order);
                 const unavailableTakerTokenAmount = await this.getUnavailableTakerAmountAsync(orderHash);
-                this._orderValidationUtils.validateCancelOrderThrowIfInvalid(
+                OrderValidationUtils.validateCancelOrderThrowIfInvalid(
                     orderCancellationRequest.order, orderCancellationRequest.takerTokenCancelAmount,
                     unavailableTakerTokenAmount,
                 );
@@ -767,7 +767,7 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.isValidBaseUnitAmount('cancelTakerTokenAmount', cancelTakerTokenAmount);
         const orderHash = utils.getOrderHashHex(order);
         const unavailableTakerTokenAmount = await this.getUnavailableTakerAmountAsync(orderHash);
-        this._orderValidationUtils.validateCancelOrderThrowIfInvalid(
+        OrderValidationUtils.validateCancelOrderThrowIfInvalid(
             order, cancelTakerTokenAmount, unavailableTakerTokenAmount);
     }
     /**
@@ -884,4 +884,4 @@ export class ExchangeWrapper extends ContractWrapper {
         const tokenTransferProxyAddressLowerCase = tokenTransferProxyAddress.toLowerCase();
         return tokenTransferProxyAddressLowerCase;
     }
-}
+} // tslint:disable:max-file-line-count
diff --git a/packages/0x.js/src/contract_wrappers/token_registry_wrapper.ts b/packages/0x.js/src/contract_wrappers/token_registry_wrapper.ts
index 60fe7f33a..468e58350 100644
--- a/packages/0x.js/src/contract_wrappers/token_registry_wrapper.ts
+++ b/packages/0x.js/src/contract_wrappers/token_registry_wrapper.ts
@@ -14,6 +14,18 @@ import {ContractWrapper} from './contract_wrapper';
 export class TokenRegistryWrapper extends ContractWrapper {
     private _tokenRegistryContractIfExists?: TokenRegistryContract;
     private _contractAddressIfExists?: string;
+    private static _createTokenFromMetadata(metadata: TokenMetadata): Token|undefined {
+        if (metadata[0] === constants.NULL_ADDRESS) {
+            return undefined;
+        }
+        const token = {
+            address: metadata[0],
+            name: metadata[1],
+            symbol: metadata[2],
+            decimals: metadata[3].toNumber(),
+        };
+        return token;
+    }
     constructor(web3Wrapper: Web3Wrapper, contractAddressIfExists?: string) {
         super(web3Wrapper);
         this._contractAddressIfExists = contractAddressIfExists;
@@ -51,7 +63,7 @@ export class TokenRegistryWrapper extends ContractWrapper {
 
         const tokenRegistryContract = await this._getTokenRegistryContractAsync();
         const metadata = await tokenRegistryContract.getTokenMetaData.callAsync(address);
-        const token = this._createTokenFromMetadata(metadata);
+        const token = TokenRegistryWrapper._createTokenFromMetadata(metadata);
         return token;
     }
     public async getTokenAddressBySymbolIfExistsAsync(symbol: string): Promise<string|undefined> {
@@ -76,14 +88,14 @@ export class TokenRegistryWrapper extends ContractWrapper {
         assert.isString('symbol', symbol);
         const tokenRegistryContract = await this._getTokenRegistryContractAsync();
         const metadata = await tokenRegistryContract.getTokenBySymbol.callAsync(symbol);
-        const token = this._createTokenFromMetadata(metadata);
+        const token = TokenRegistryWrapper._createTokenFromMetadata(metadata);
         return token;
     }
     public async getTokenByNameIfExistsAsync(name: string): Promise<Token|undefined> {
         assert.isString('name', name);
         const tokenRegistryContract = await this._getTokenRegistryContractAsync();
         const metadata = await tokenRegistryContract.getTokenByName.callAsync(name);
-        const token = this._createTokenFromMetadata(metadata);
+        const token = TokenRegistryWrapper._createTokenFromMetadata(metadata);
         return token;
     }
     /**
@@ -103,18 +115,6 @@ export class TokenRegistryWrapper extends ContractWrapper {
             return this._contractAddressIfExists;
         }
     }
-    private _createTokenFromMetadata(metadata: TokenMetadata): Token|undefined {
-        if (metadata[0] === constants.NULL_ADDRESS) {
-            return undefined;
-        }
-        const token = {
-            address: metadata[0],
-            name: metadata[1],
-            symbol: metadata[2],
-            decimals: metadata[3].toNumber(),
-        };
-        return token;
-    }
     private _invalidateContractInstance(): void {
         delete this._tokenRegistryContractIfExists;
     }
diff --git a/packages/0x.js/src/order_watcher/order_state_watcher.ts b/packages/0x.js/src/order_watcher/order_state_watcher.ts
index 4d57935a1..919a58df7 100644
--- a/packages/0x.js/src/order_watcher/order_state_watcher.ts
+++ b/packages/0x.js/src/order_watcher/order_state_watcher.ts
@@ -38,7 +38,7 @@ import {ExpirationWatcher} from './expiration_watcher';
 
 interface DependentOrderHashes {
     [makerAddress: string]: {
-        [makerToken: string]: Set<string>,
+        [makerToken: string]: Set<string>;
     };
 }
 
diff --git a/packages/0x.js/src/stores/balance_proxy_allowance_lazy_store.ts b/packages/0x.js/src/stores/balance_proxy_allowance_lazy_store.ts
index 293f75db9..afc40b86d 100644
--- a/packages/0x.js/src/stores/balance_proxy_allowance_lazy_store.ts
+++ b/packages/0x.js/src/stores/balance_proxy_allowance_lazy_store.ts
@@ -12,13 +12,13 @@ export class BalanceAndProxyAllowanceLazyStore {
     private token: TokenWrapper;
     private balance: {
         [tokenAddress: string]: {
-            [userAddress: string]: BigNumber,
-        },
+            [userAddress: string]: BigNumber;
+        };
     };
     private proxyAllowance: {
         [tokenAddress: string]: {
-            [userAddress: string]: BigNumber,
-        },
+            [userAddress: string]: BigNumber;
+        };
     };
     constructor(token: TokenWrapper) {
         this.token = token;
diff --git a/packages/0x.js/src/stores/order_filled_cancelled_lazy_store.ts b/packages/0x.js/src/stores/order_filled_cancelled_lazy_store.ts
index 59c1bb7a7..28b32f9e2 100644
--- a/packages/0x.js/src/stores/order_filled_cancelled_lazy_store.ts
+++ b/packages/0x.js/src/stores/order_filled_cancelled_lazy_store.ts
@@ -11,10 +11,10 @@ import {BlockParamLiteral} from '../types';
 export class OrderFilledCancelledLazyStore {
     private exchange: ExchangeWrapper;
     private filledTakerAmount: {
-        [orderHash: string]: BigNumber,
+        [orderHash: string]: BigNumber;
     };
     private cancelledTakerAmount: {
-        [orderHash: string]: BigNumber,
+        [orderHash: string]: BigNumber;
     };
     constructor(exchange: ExchangeWrapper) {
         this.exchange = exchange;
diff --git a/packages/0x.js/src/subproviders/empty_wallet_subprovider.ts b/packages/0x.js/src/subproviders/empty_wallet_subprovider.ts
index 2f260217c..d707d5652 100644
--- a/packages/0x.js/src/subproviders/empty_wallet_subprovider.ts
+++ b/packages/0x.js/src/subproviders/empty_wallet_subprovider.ts
@@ -6,6 +6,7 @@ import {JSONRPCPayload} from '../types';
  * Source: https://github.com/MetaMask/provider-engine/blob/master/subproviders/subprovider.js
  */
 export class EmptyWalletSubProvider {
+    // tslint:disable-next-line:prefer-function-over-method
     public handleRequest(payload: JSONRPCPayload, next: () => void, end: (err: Error|null, result: any) => void) {
         switch (payload.method) {
             case 'eth_accounts':
@@ -18,6 +19,7 @@ export class EmptyWalletSubProvider {
         }
     }
     // Required to implement this method despite not needing it for this subprovider
+    // tslint:disable-next-line:prefer-function-over-method
     public setEngine(engine: any) {
         // noop
     }
diff --git a/packages/0x.js/src/utils/abi_decoder.ts b/packages/0x.js/src/utils/abi_decoder.ts
index f027026da..f26b057f0 100644
--- a/packages/0x.js/src/utils/abi_decoder.ts
+++ b/packages/0x.js/src/utils/abi_decoder.ts
@@ -8,6 +8,15 @@ import {AbiType, ContractEventArgs, DecodedLogArgs, LogWithDecodedArgs, RawLog,
 export class AbiDecoder {
     private savedABIs: Web3.AbiDefinition[] = [];
     private methodIds: {[signatureHash: string]: Web3.EventAbi} = {};
+    private static padZeros(address: string) {
+        let formatted = address;
+        if (_.startsWith(formatted, '0x')) {
+            formatted = formatted.slice(2);
+        }
+
+        formatted = _.padStart(formatted, 40, '0');
+        return `0x${formatted}`;
+    }
     constructor(abiArrays: Web3.AbiDefinition[][]) {
         _.map(abiArrays, this.addABI.bind(this));
     }
@@ -32,7 +41,7 @@ export class AbiDecoder {
             // Indexed parameters are stored in topics. Non-indexed ones in decodedData
             let value = param.indexed ? log.topics[topicsIndex++] : decodedData[dataIndex++];
             if (param.type === SolidityTypes.Address) {
-                value = this.padZeros(new BigNumber(value).toString(16));
+                value = AbiDecoder.padZeros(new BigNumber(value).toString(16));
             } else if (param.type === SolidityTypes.Uint256 ||
                        param.type === SolidityTypes.Uint8 ||
                        param.type === SolidityTypes.Uint) {
@@ -57,13 +66,4 @@ export class AbiDecoder {
         });
         this.savedABIs = this.savedABIs.concat(abiArray);
     }
-    private padZeros(address: string) {
-        let formatted = address;
-        if (_.startsWith(formatted, '0x')) {
-            formatted = formatted.slice(2);
-        }
-
-        formatted = _.padStart(formatted, 40, '0');
-        return `0x${formatted}`;
-    }
 }
diff --git a/packages/0x.js/src/utils/exchange_transfer_simulator.ts b/packages/0x.js/src/utils/exchange_transfer_simulator.ts
index c3a2d1585..00a0efd3f 100644
--- a/packages/0x.js/src/utils/exchange_transfer_simulator.ts
+++ b/packages/0x.js/src/utils/exchange_transfer_simulator.ts
@@ -36,6 +36,11 @@ const ERR_MSG_MAPPING = {
 export class ExchangeTransferSimulator {
     private store: BalanceAndProxyAllowanceLazyStore;
     private UNLIMITED_ALLOWANCE_IN_BASE_UNITS: BigNumber;
+    private static throwValidationError(failureReason: FailureReason, tradeSide: TradeSide,
+                                        transferType: TransferType): never {
+        const errMsg = ERR_MSG_MAPPING[failureReason][tradeSide][transferType];
+        throw new Error(errMsg);
+    }
     constructor(token: TokenWrapper) {
         this.store = new BalanceAndProxyAllowanceLazyStore(token);
         this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS = token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
@@ -55,10 +60,10 @@ export class ExchangeTransferSimulator {
         const balance = await this.store.getBalanceAsync(tokenAddress, from);
         const proxyAllowance = await this.store.getProxyAllowanceAsync(tokenAddress, from);
         if (proxyAllowance.lessThan(amountInBaseUnits)) {
-            this.throwValidationError(FailureReason.ProxyAllowance, tradeSide, transferType);
+            ExchangeTransferSimulator.throwValidationError(FailureReason.ProxyAllowance, tradeSide, transferType);
         }
         if (balance.lessThan(amountInBaseUnits)) {
-            this.throwValidationError(FailureReason.Balance, tradeSide, transferType);
+            ExchangeTransferSimulator.throwValidationError(FailureReason.Balance, tradeSide, transferType);
         }
         await this.decreaseProxyAllowanceAsync(tokenAddress, from, amountInBaseUnits);
         await this.decreaseBalanceAsync(tokenAddress, from, amountInBaseUnits);
@@ -81,9 +86,4 @@ export class ExchangeTransferSimulator {
         const balance = await this.store.getBalanceAsync(tokenAddress, userAddress);
         this.store.setBalance(tokenAddress, userAddress, balance.minus(amountInBaseUnits));
     }
-    private throwValidationError(failureReason: FailureReason, tradeSide: TradeSide,
-                                 transferType: TransferType): never {
-        const errMsg = ERR_MSG_MAPPING[failureReason][tradeSide][transferType];
-        throw new Error(errMsg);
-    }
 }
diff --git a/packages/0x.js/src/utils/order_state_utils.ts b/packages/0x.js/src/utils/order_state_utils.ts
index 6654b9ae1..7dee89914 100644
--- a/packages/0x.js/src/utils/order_state_utils.ts
+++ b/packages/0x.js/src/utils/order_state_utils.ts
@@ -25,6 +25,39 @@ const ACCEPTABLE_RELATIVE_ROUNDING_ERROR = 0.0001;
 export class OrderStateUtils {
     private balanceAndProxyAllowanceLazyStore: BalanceAndProxyAllowanceLazyStore;
     private orderFilledCancelledLazyStore: OrderFilledCancelledLazyStore;
+    private static validateIfOrderIsValid(signedOrder: SignedOrder, orderRelevantState: OrderRelevantState): void {
+        const unavailableTakerTokenAmount = orderRelevantState.cancelledTakerTokenAmount.add(
+            orderRelevantState.filledTakerTokenAmount,
+        );
+        const availableTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
+        if (availableTakerTokenAmount.eq(0)) {
+            throw new Error(ExchangeContractErrs.OrderRemainingFillAmountZero);
+        }
+
+        if (orderRelevantState.makerBalance.eq(0)) {
+            throw new Error(ExchangeContractErrs.InsufficientMakerBalance);
+        }
+        if (orderRelevantState.makerProxyAllowance.eq(0)) {
+            throw new Error(ExchangeContractErrs.InsufficientMakerAllowance);
+        }
+        if (!signedOrder.makerFee.eq(0)) {
+            if (orderRelevantState.makerFeeBalance.eq(0)) {
+                throw new Error(ExchangeContractErrs.InsufficientMakerFeeBalance);
+            }
+            if (orderRelevantState.makerFeeProxyAllowance.eq(0)) {
+                throw new Error(ExchangeContractErrs.InsufficientMakerFeeAllowance);
+            }
+        }
+        const minFillableTakerTokenAmountWithinNoRoundingErrorRange = signedOrder.takerTokenAmount
+                                                                      .dividedBy(ACCEPTABLE_RELATIVE_ROUNDING_ERROR)
+                                                                      .dividedBy(signedOrder.makerTokenAmount);
+        if (orderRelevantState.remainingFillableTakerTokenAmount
+            .lessThan(minFillableTakerTokenAmountWithinNoRoundingErrorRange)) {
+            throw new Error(ExchangeContractErrs.OrderFillRoundingError);
+        }
+        // TODO Add linear function solver when maker token is ZRX #badass
+        // Return the max amount that's fillable
+    }
     constructor(balanceAndProxyAllowanceLazyStore: BalanceAndProxyAllowanceLazyStore,
                 orderFilledCancelledLazyStore: OrderFilledCancelledLazyStore) {
         this.balanceAndProxyAllowanceLazyStore = balanceAndProxyAllowanceLazyStore;
@@ -34,7 +67,7 @@ export class OrderStateUtils {
         const orderRelevantState = await this.getOrderRelevantStateAsync(signedOrder);
         const orderHash = ZeroEx.getOrderHashHex(signedOrder);
         try {
-            this.validateIfOrderIsValid(signedOrder, orderRelevantState);
+            OrderStateUtils.validateIfOrderIsValid(signedOrder, orderRelevantState);
             const orderState: OrderStateValid = {
                 isValid: true,
                 orderHash,
@@ -103,37 +136,4 @@ export class OrderStateUtils {
         };
         return orderRelevantState;
     }
-    private validateIfOrderIsValid(signedOrder: SignedOrder, orderRelevantState: OrderRelevantState): void {
-        const unavailableTakerTokenAmount = orderRelevantState.cancelledTakerTokenAmount.add(
-            orderRelevantState.filledTakerTokenAmount,
-        );
-        const availableTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
-        if (availableTakerTokenAmount.eq(0)) {
-            throw new Error(ExchangeContractErrs.OrderRemainingFillAmountZero);
-        }
-
-        if (orderRelevantState.makerBalance.eq(0)) {
-            throw new Error(ExchangeContractErrs.InsufficientMakerBalance);
-        }
-        if (orderRelevantState.makerProxyAllowance.eq(0)) {
-            throw new Error(ExchangeContractErrs.InsufficientMakerAllowance);
-        }
-        if (!signedOrder.makerFee.eq(0)) {
-            if (orderRelevantState.makerFeeBalance.eq(0)) {
-                throw new Error(ExchangeContractErrs.InsufficientMakerFeeBalance);
-            }
-            if (orderRelevantState.makerFeeProxyAllowance.eq(0)) {
-                throw new Error(ExchangeContractErrs.InsufficientMakerFeeAllowance);
-            }
-        }
-        const minFillableTakerTokenAmountWithinNoRoundingErrorRange = signedOrder.takerTokenAmount
-                                                                      .dividedBy(ACCEPTABLE_RELATIVE_ROUNDING_ERROR)
-                                                                      .dividedBy(signedOrder.makerTokenAmount);
-        if (orderRelevantState.remainingFillableTakerTokenAmount
-            .lessThan(minFillableTakerTokenAmountWithinNoRoundingErrorRange)) {
-            throw new Error(ExchangeContractErrs.OrderFillRoundingError);
-        }
-        // TODO Add linear function solver when maker token is ZRX #badass
-        // Return the max amount that's fillable
-    }
 }
diff --git a/packages/0x.js/src/utils/order_validation_utils.ts b/packages/0x.js/src/utils/order_validation_utils.ts
index 06cfca7bd..d514483e0 100644
--- a/packages/0x.js/src/utils/order_validation_utils.ts
+++ b/packages/0x.js/src/utils/order_validation_utils.ts
@@ -13,6 +13,77 @@ import {ExchangeTransferSimulator} from './exchange_transfer_simulator';
 export class OrderValidationUtils {
     private tokenWrapper: TokenWrapper;
     private exchangeWrapper: ExchangeWrapper;
+    public static validateCancelOrderThrowIfInvalid(
+        order: Order, cancelTakerTokenAmount: BigNumber, unavailableTakerTokenAmount: BigNumber,
+    ): void {
+        if (cancelTakerTokenAmount.eq(0)) {
+            throw new Error(ExchangeContractErrs.OrderCancelAmountZero);
+        }
+        if (order.takerTokenAmount.eq(unavailableTakerTokenAmount)) {
+            throw new Error(ExchangeContractErrs.OrderAlreadyCancelledOrFilled);
+        }
+        const currentUnixTimestampSec = utils.getCurrentUnixTimestampSec();
+        if (order.expirationUnixTimestampSec.lessThan(currentUnixTimestampSec)) {
+            throw new Error(ExchangeContractErrs.OrderCancelExpired);
+        }
+    }
+    public static async validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+        exchangeTradeEmulator: ExchangeTransferSimulator, signedOrder: SignedOrder,
+        fillTakerTokenAmount: BigNumber, senderAddress: string, zrxTokenAddress: string,
+    ): Promise<void> {
+        const fillMakerTokenAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.makerTokenAmount,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            signedOrder.makerTokenAddress, signedOrder.maker, senderAddress, fillMakerTokenAmount,
+            TradeSide.Maker, TransferType.Trade,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            signedOrder.takerTokenAddress, senderAddress, signedOrder.maker, fillTakerTokenAmount,
+            TradeSide.Taker, TransferType.Trade,
+        );
+        const makerFeeAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.makerFee,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            zrxTokenAddress, signedOrder.maker, signedOrder.feeRecipient, makerFeeAmount, TradeSide.Maker,
+            TransferType.Fee,
+        );
+        const takerFeeAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.takerFee,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            zrxTokenAddress, senderAddress, signedOrder.feeRecipient, takerFeeAmount, TradeSide.Taker,
+            TransferType.Fee,
+        );
+    }
+    private static validateRemainingFillAmountNotZeroOrThrow(
+        takerTokenAmount: BigNumber, unavailableTakerTokenAmount: BigNumber,
+    ) {
+        if (takerTokenAmount.eq(unavailableTakerTokenAmount)) {
+            throw new Error(ExchangeContractErrs.OrderRemainingFillAmountZero);
+        }
+    }
+    private static validateOrderNotExpiredOrThrow(expirationUnixTimestampSec: BigNumber) {
+        const currentUnixTimestampSec = utils.getCurrentUnixTimestampSec();
+        if (expirationUnixTimestampSec.lessThan(currentUnixTimestampSec)) {
+            throw new Error(ExchangeContractErrs.OrderFillExpired);
+        }
+    }
+    private static getPartialAmount(numerator: BigNumber, denominator: BigNumber,
+                                    target: BigNumber): BigNumber {
+        const fillMakerTokenAmount = numerator
+                                     .mul(target)
+                                     .div(denominator)
+                                     .round(0);
+        return fillMakerTokenAmount;
+    }
     constructor(tokenWrapper: TokenWrapper, exchangeWrapper: ExchangeWrapper) {
         this.tokenWrapper = tokenWrapper;
         this.exchangeWrapper = exchangeWrapper;
@@ -22,15 +93,15 @@ export class OrderValidationUtils {
         expectedFillTakerTokenAmount?: BigNumber): Promise<void> {
         const orderHash = utils.getOrderHashHex(signedOrder);
         const unavailableTakerTokenAmount = await this.exchangeWrapper.getUnavailableTakerAmountAsync(orderHash);
-        this.validateRemainingFillAmountNotZeroOrThrow(
+        OrderValidationUtils.validateRemainingFillAmountNotZeroOrThrow(
             signedOrder.takerTokenAmount, unavailableTakerTokenAmount,
         );
-        this.validateOrderNotExpiredOrThrow(signedOrder.expirationUnixTimestampSec);
+        OrderValidationUtils.validateOrderNotExpiredOrThrow(signedOrder.expirationUnixTimestampSec);
         let fillTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
         if (!_.isUndefined(expectedFillTakerTokenAmount)) {
             fillTakerTokenAmount = expectedFillTakerTokenAmount;
         }
-        const fillMakerTokenAmount = this.getPartialAmount(
+        const fillMakerTokenAmount = OrderValidationUtils.getPartialAmount(
             fillTakerTokenAmount,
             signedOrder.takerTokenAmount,
             signedOrder.makerTokenAmount,
@@ -39,7 +110,7 @@ export class OrderValidationUtils {
             signedOrder.makerTokenAddress, signedOrder.maker, signedOrder.taker, fillMakerTokenAmount,
             TradeSide.Maker, TransferType.Trade,
         );
-        const makerFeeAmount = this.getPartialAmount(
+        const makerFeeAmount = OrderValidationUtils.getPartialAmount(
             fillTakerTokenAmount,
             signedOrder.takerTokenAmount,
             signedOrder.makerFee,
@@ -61,18 +132,18 @@ export class OrderValidationUtils {
             throw new Error(ZeroExError.InvalidSignature);
         }
         const unavailableTakerTokenAmount = await this.exchangeWrapper.getUnavailableTakerAmountAsync(orderHash);
-        this.validateRemainingFillAmountNotZeroOrThrow(
+        OrderValidationUtils.validateRemainingFillAmountNotZeroOrThrow(
             signedOrder.takerTokenAmount, unavailableTakerTokenAmount,
         );
         if (signedOrder.taker !== constants.NULL_ADDRESS && signedOrder.taker !== takerAddress) {
             throw new Error(ExchangeContractErrs.TransactionSenderIsNotFillOrderTaker);
         }
-        this.validateOrderNotExpiredOrThrow(signedOrder.expirationUnixTimestampSec);
+        OrderValidationUtils.validateOrderNotExpiredOrThrow(signedOrder.expirationUnixTimestampSec);
         const remainingTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
         const filledTakerTokenAmount = remainingTakerTokenAmount.lessThan(fillTakerTokenAmount) ?
                                        remainingTakerTokenAmount :
                                        fillTakerTokenAmount;
-        await this.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+        await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
             exchangeTradeEmulator, signedOrder, filledTakerTokenAmount, takerAddress, zrxTokenAddress,
         );
 
@@ -94,74 +165,4 @@ export class OrderValidationUtils {
             throw new Error(ExchangeContractErrs.InsufficientRemainingFillAmount);
         }
     }
-    public validateCancelOrderThrowIfInvalid(
-        order: Order, cancelTakerTokenAmount: BigNumber, unavailableTakerTokenAmount: BigNumber,
-    ): void {
-        if (cancelTakerTokenAmount.eq(0)) {
-            throw new Error(ExchangeContractErrs.OrderCancelAmountZero);
-        }
-        if (order.takerTokenAmount.eq(unavailableTakerTokenAmount)) {
-            throw new Error(ExchangeContractErrs.OrderAlreadyCancelledOrFilled);
-        }
-        const currentUnixTimestampSec = utils.getCurrentUnixTimestampSec();
-        if (order.expirationUnixTimestampSec.lessThan(currentUnixTimestampSec)) {
-            throw new Error(ExchangeContractErrs.OrderCancelExpired);
-        }
-    }
-    public async validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
-        exchangeTradeEmulator: ExchangeTransferSimulator, signedOrder: SignedOrder,
-        fillTakerTokenAmount: BigNumber, senderAddress: string, zrxTokenAddress: string): Promise<void> {
-        const fillMakerTokenAmount = this.getPartialAmount(
-            fillTakerTokenAmount,
-            signedOrder.takerTokenAmount,
-            signedOrder.makerTokenAmount,
-        );
-        await exchangeTradeEmulator.transferFromAsync(
-            signedOrder.makerTokenAddress, signedOrder.maker, senderAddress, fillMakerTokenAmount,
-            TradeSide.Maker, TransferType.Trade,
-        );
-        await exchangeTradeEmulator.transferFromAsync(
-            signedOrder.takerTokenAddress, senderAddress, signedOrder.maker, fillTakerTokenAmount,
-            TradeSide.Taker, TransferType.Trade,
-        );
-        const makerFeeAmount = this.getPartialAmount(
-            fillTakerTokenAmount,
-            signedOrder.takerTokenAmount,
-            signedOrder.makerFee,
-        );
-        await exchangeTradeEmulator.transferFromAsync(
-            zrxTokenAddress, signedOrder.maker, signedOrder.feeRecipient, makerFeeAmount, TradeSide.Maker,
-            TransferType.Fee,
-        );
-        const takerFeeAmount = this.getPartialAmount(
-            fillTakerTokenAmount,
-            signedOrder.takerTokenAmount,
-            signedOrder.takerFee,
-        );
-        await exchangeTradeEmulator.transferFromAsync(
-            zrxTokenAddress, senderAddress, signedOrder.feeRecipient, takerFeeAmount, TradeSide.Taker,
-            TransferType.Fee,
-        );
-    }
-    private validateRemainingFillAmountNotZeroOrThrow(
-        takerTokenAmount: BigNumber, unavailableTakerTokenAmount: BigNumber,
-    ) {
-        if (takerTokenAmount.eq(unavailableTakerTokenAmount)) {
-            throw new Error(ExchangeContractErrs.OrderRemainingFillAmountZero);
-        }
-    }
-    private validateOrderNotExpiredOrThrow(expirationUnixTimestampSec: BigNumber) {
-        const currentUnixTimestampSec = utils.getCurrentUnixTimestampSec();
-        if (expirationUnixTimestampSec.lessThan(currentUnixTimestampSec)) {
-            throw new Error(ExchangeContractErrs.OrderFillExpired);
-        }
-    }
-    private getPartialAmount(numerator: BigNumber, denominator: BigNumber,
-                             target: BigNumber): BigNumber {
-        const fillMakerTokenAmount = numerator
-                                     .mul(target)
-                                     .div(denominator)
-                                     .round(0);
-        return fillMakerTokenAmount;
-    }
 }
diff --git a/packages/0x.js/test/order_validation_test.ts b/packages/0x.js/test/order_validation_test.ts
index 811cd48c4..3282ebb3e 100644
--- a/packages/0x.js/test/order_validation_test.ts
+++ b/packages/0x.js/test/order_validation_test.ts
@@ -114,7 +114,7 @@ describe('OrderValidation', () => {
                 makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
             );
             // 27 <--> 28
-            signedOrder.ecSignature.v = 27 + (28 - signedOrder.ecSignature.v);
+            signedOrder.ecSignature.v = (28 - signedOrder.ecSignature.v) + 27;
             return expect(zeroEx.exchange.validateFillOrderThrowIfInvalidAsync(
                 signedOrder, fillableAmount, takerAddress,
             )).to.be.rejectedWith(ZeroExError.InvalidSignature);
@@ -230,7 +230,7 @@ describe('OrderValidation', () => {
                 makerTokenAddress, takerTokenAddress, makerFee, takerFee,
                 makerAddress, takerAddress, fillableAmount, feeRecipient,
             );
-            await orderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
                 exchangeTransferSimulator, signedOrder, fillableAmount, takerAddress, zrxTokenAddress,
             );
             expect(transferFromAsync.callCount).to.be.equal(4);
@@ -266,7 +266,7 @@ describe('OrderValidation', () => {
                 makerTokenAddress, takerTokenAddress, makerFee, takerFee,
                 makerAddress, ZeroEx.NULL_ADDRESS, fillableAmount, feeRecipient,
             );
-            await orderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
                 exchangeTransferSimulator, signedOrder, fillableAmount, takerAddress, zrxTokenAddress,
             );
             expect(transferFromAsync.callCount).to.be.equal(4);
@@ -301,7 +301,7 @@ describe('OrderValidation', () => {
             const signedOrder = await fillScenarios.createAsymmetricFillableSignedOrderAsync(
                 makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, makerTokenAmount, takerTokenAmount,
             );
-            await orderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
                 exchangeTransferSimulator, signedOrder, takerTokenAmount, takerAddress, zrxTokenAddress,
             );
             expect(transferFromAsync.callCount).to.be.equal(4);
@@ -316,7 +316,7 @@ describe('OrderValidation', () => {
                 fillableAmount, ZeroEx.NULL_ADDRESS,
             );
             const fillTakerTokenAmount = fillableAmount.div(2).round(0);
-            await orderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
                 exchangeTransferSimulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress,
             );
             const makerPartialFee = makerFee.div(2);