2 files changed, 16 insertions, 14 deletions

diff --git a/packages/contract-wrappers/src/utils/exchange_transfer_simulator.ts b/packages/contract-wrappers/src/utils/exchange_transfer_simulator.ts
index 395945fe3..527b8575d 100644
--- a/packages/contract-wrappers/src/utils/exchange_transfer_simulator.ts
+++ b/packages/contract-wrappers/src/utils/exchange_transfer_simulator.ts
@@ -1,8 +1,8 @@
 import { BlockParamLiteral, ExchangeContractErrs } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 
+import { AbstractBalanceAndProxyAllowanceLazyStore } from '../abstract/abstract_balance_and_proxy_allowance_lazy_store';
 import { TokenWrapper } from '../contract_wrappers/token_wrapper';
-import { BalanceAndProxyAllowanceLazyStore } from '../stores/balance_proxy_allowance_lazy_store';
 import { TradeSide, TransferType } from '../types';
 import { constants } from '../utils/constants';
 
@@ -35,8 +35,7 @@ const ERR_MSG_MAPPING = {
 };
 
 export class ExchangeTransferSimulator {
-    private _store: BalanceAndProxyAllowanceLazyStore;
-    private _UNLIMITED_ALLOWANCE_IN_BASE_UNITS: BigNumber;
+    private _store: AbstractBalanceAndProxyAllowanceLazyStore;
     private static _throwValidationError(
         failureReason: FailureReason,
         tradeSide: TradeSide,
@@ -45,9 +44,8 @@ export class ExchangeTransferSimulator {
         const errMsg = ERR_MSG_MAPPING[failureReason][tradeSide][transferType];
         throw new Error(errMsg);
     }
-    constructor(token: TokenWrapper, defaultBlock: BlockParamLiteral) {
-        this._store = new BalanceAndProxyAllowanceLazyStore(token, defaultBlock);
-        this._UNLIMITED_ALLOWANCE_IN_BASE_UNITS = token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
+    constructor(store: AbstractBalanceAndProxyAllowanceLazyStore) {
+        this._store = store;
     }
     /**
      * Simulates transferFrom call performed by a proxy
@@ -91,7 +89,7 @@ export class ExchangeTransferSimulator {
         amountInBaseUnits: BigNumber,
     ): Promise<void> {
         const proxyAllowance = await this._store.getProxyAllowanceAsync(tokenAddress, userAddress);
-        if (!proxyAllowance.eq(this._UNLIMITED_ALLOWANCE_IN_BASE_UNITS)) {
+        if (!proxyAllowance.eq(constants.UNLIMITED_ALLOWANCE_IN_BASE_UNITS)) {
             this._store.setProxyAllowance(tokenAddress, userAddress, proxyAllowance.minus(amountInBaseUnits));
         }
     }
diff --git a/packages/contract-wrappers/src/utils/order_validation_utils.ts b/packages/contract-wrappers/src/utils/order_validation_utils.ts
index b6b3334a6..c6ef26275 100644
--- a/packages/contract-wrappers/src/utils/order_validation_utils.ts
+++ b/packages/contract-wrappers/src/utils/order_validation_utils.ts
@@ -3,7 +3,7 @@ import { ExchangeContractErrs, Order, SignedOrder } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as _ from 'lodash';
 
-import { ExchangeWrapper } from '../contract_wrappers/exchange_wrapper';
+import { ExchangeContract } from '../contract_wrappers/generated/exchange';
 import { TradeSide, TransferType } from '../types';
 import { constants } from '../utils/constants';
 import { utils } from '../utils/utils';
@@ -11,7 +11,7 @@ import { utils } from '../utils/utils';
 import { ExchangeTransferSimulator } from './exchange_transfer_simulator';
 
 export class OrderValidationUtils {
-    private _exchangeWrapper: ExchangeWrapper;
+    private _exchangeContract: ExchangeContract;
     public static validateCancelOrderThrowIfInvalid(
         order: Order,
         cancelTakerTokenAmount: BigNumber,
@@ -104,8 +104,8 @@ export class OrderValidationUtils {
             .round(0);
         return fillMakerTokenAmount;
     }
-    constructor(exchangeWrapper: ExchangeWrapper) {
-        this._exchangeWrapper = exchangeWrapper;
+    constructor(exchangeContract: ExchangeContract) {
+        this._exchangeContract = exchangeContract;
     }
     public async validateOrderFillableOrThrowAsync(
         exchangeTradeEmulator: ExchangeTransferSimulator,
@@ -114,7 +114,9 @@ export class OrderValidationUtils {
         expectedFillTakerTokenAmount?: BigNumber,
     ): Promise<void> {
         const orderHash = getOrderHashHex(signedOrder);
-        const unavailableTakerTokenAmount = await this._exchangeWrapper.getUnavailableTakerAmountAsync(orderHash);
+        const unavailableTakerTokenAmount = await this._exchangeContract.getUnavailableTakerTokenAmount.callAsync(
+            orderHash,
+        );
         OrderValidationUtils._validateRemainingFillAmountNotZeroOrThrow(
             signedOrder.takerTokenAmount,
             unavailableTakerTokenAmount,
@@ -146,7 +148,9 @@ export class OrderValidationUtils {
         if (!isValidSignature(orderHash, signedOrder.ecSignature, signedOrder.maker)) {
             throw new Error(OrderError.InvalidSignature);
         }
-        const unavailableTakerTokenAmount = await this._exchangeWrapper.getUnavailableTakerAmountAsync(orderHash);
+        const unavailableTakerTokenAmount = await this._exchangeContract.getUnavailableTakerTokenAmount.callAsync(
+            orderHash,
+        );
         OrderValidationUtils._validateRemainingFillAmountNotZeroOrThrow(
             signedOrder.takerTokenAmount,
             unavailableTakerTokenAmount,
@@ -167,7 +171,7 @@ export class OrderValidationUtils {
             zrxTokenAddress,
         );
 
-        const wouldRoundingErrorOccur = await this._exchangeWrapper.isRoundingErrorAsync(
+        const wouldRoundingErrorOccur = await this._exchangeContract.isRoundingError.callAsync(
             filledTakerTokenAmount,
             signedOrder.takerTokenAmount,
             signedOrder.makerTokenAmount,