Refactor ExchangeTransferSimulator public interface to accet an AbstractBalanceAndProxyAllowanceLazyStore so that this module could be re-used in different contexts.

packages/contract-wrappers/src/abstract/abstract_balance_and_proxy_allowance_lazy_store.ts

@@ -0,0 +1,11 @@
+import { BigNumber } from '@0xproject/utils';
+
+export abstract class AbstractBalanceAndProxyAllowanceLazyStore {
+    public abstract async getBalanceAsync(tokenAddress: string, userAddress: string): Promise<BigNumber>;
+    public abstract async getProxyAllowanceAsync(tokenAddress: string, userAddress: string): Promise<BigNumber>;
+    public abstract setBalance(tokenAddress: string, userAddress: string, balance: BigNumber): void;
+    public abstract deleteBalance(tokenAddress: string, userAddress: string): void;
+    public abstract setProxyAllowance(tokenAddress: string, userAddress: string, proxyAllowance: BigNumber): void;
+    public abstract deleteProxyAllowance(tokenAddress: string, userAddress: string): void;
+    public abstract deleteAll(): void;
+}

packages/contract-wrappers/src/contract_wrappers/exchange_wrapper.ts

@@ -18,6 +18,7 @@ import * as _ from 'lodash';
 import { artifacts } from '../artifacts';
 import { SimpleBalanceAndProxyAllowanceFetcher } from '../fetchers/simple_balance_and_proxy_allowance_fetcher';
 import { SimpleOrderFilledCancelledFetcher } from '../fetchers/simple_order_filled_cancelled_fetcher';
+import { BalanceAndProxyAllowanceLazyStore } from '../stores/balance_proxy_allowance_lazy_store';
 import {
     BlockRange,
     EventCallback,
@@ -177,7 +178,11 @@ export class ExchangeWrapper extends ContractWrapper {
             : orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
             const zrxTokenAddress = this.getZRXTokenAddress();
-            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+                this._tokenWrapper,
+                BlockParamLiteral.Latest,
+            );
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
             await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
                 exchangeTradeEmulator,
                 signedOrder,
@@ -252,7 +257,11 @@ export class ExchangeWrapper extends ContractWrapper {
         if (shouldValidate) {
             let filledTakerTokenAmount = new BigNumber(0);
             const zrxTokenAddress = this.getZRXTokenAddress();
-            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+                this._tokenWrapper,
+                BlockParamLiteral.Latest,
+            );
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
             for (const signedOrder of signedOrders) {
                 const singleFilledTakerTokenAmount = await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
                     exchangeTradeEmulator,
@@ -345,7 +354,11 @@ export class ExchangeWrapper extends ContractWrapper {
             : orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
             const zrxTokenAddress = this.getZRXTokenAddress();
-            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+                this._tokenWrapper,
+                BlockParamLiteral.Latest,
+            );
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
             for (const orderFillRequest of orderFillRequests) {
                 await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
                     exchangeTradeEmulator,
@@ -421,7 +434,11 @@ export class ExchangeWrapper extends ContractWrapper {
             : orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
             const zrxTokenAddress = this.getZRXTokenAddress();
-            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+                this._tokenWrapper,
+                BlockParamLiteral.Latest,
+            );
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
             await this._orderValidationUtils.validateFillOrKillOrderThrowIfInvalidAsync(
                 exchangeTradeEmulator,
                 signedOrder,
@@ -483,7 +500,11 @@ export class ExchangeWrapper extends ContractWrapper {
             : orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
             const zrxTokenAddress = this.getZRXTokenAddress();
-            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+                this._tokenWrapper,
+                BlockParamLiteral.Latest,
+            );
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
             for (const orderFillRequest of orderFillRequests) {
                 await this._orderValidationUtils.validateFillOrKillOrderThrowIfInvalidAsync(
                     exchangeTradeEmulator,
@@ -733,7 +754,11 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
         const zrxTokenAddress = this.getZRXTokenAddress();
         const expectedFillTakerTokenAmount = !_.isUndefined(opts) ? opts.expectedFillTakerTokenAmount : undefined;
-        const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+        const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+            this._tokenWrapper,
+            BlockParamLiteral.Latest,
+        );
+        const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
         await this._orderValidationUtils.validateOrderFillableOrThrowAsync(
             exchangeTradeEmulator,
             signedOrder,
@@ -759,7 +784,11 @@ export class ExchangeWrapper extends ContractWrapper {
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
         const normalizedTakerAddress = takerAddress.toLowerCase();
         const zrxTokenAddress = this.getZRXTokenAddress();
-        const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+        const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+            this._tokenWrapper,
+            BlockParamLiteral.Latest,
+        );
+        const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
         await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
             exchangeTradeEmulator,
             signedOrder,
@@ -806,7 +835,11 @@ export class ExchangeWrapper extends ContractWrapper {
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
         const normalizedTakerAddress = takerAddress.toLowerCase();
         const zrxTokenAddress = this.getZRXTokenAddress();
-        const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+        const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+            this._tokenWrapper,
+            BlockParamLiteral.Latest,
+        );
+        const exchangeTradeEmulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
         await this._orderValidationUtils.validateFillOrKillOrderThrowIfInvalidAsync(
             exchangeTradeEmulator,
             signedOrder,

packages/contract-wrappers/src/stores/balance_proxy_allowance_lazy_store.ts

@@ -1,14 +1,14 @@
-import { AbstractBalanceAndProxyAllowanceFetcher } from '@0xproject/order-utils';
 import { BlockParamLiteral } from '@0xproject/types';
 import { BigNumber } from '@0xproject/utils';
 import * as _ from 'lodash';
 
+import { AbstractBalanceAndProxyAllowanceLazyStore } from '../abstract/abstract_balance_and_proxy_allowance_lazy_store';
 import { TokenWrapper } from '../contract_wrappers/token_wrapper';
 
 /**
  * Copy on read store for balances/proxyAllowances of tokens/accounts
  */
-export class BalanceAndProxyAllowanceLazyStore implements AbstractBalanceAndProxyAllowanceFetcher {
+export class BalanceAndProxyAllowanceLazyStore implements AbstractBalanceAndProxyAllowanceLazyStore {
     private _tokenWrapper: TokenWrapper;
     private _defaultBlock: BlockParamLiteral;
     private _balance: {

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 _store: AbstractBalanceAndProxyAllowanceLazyStore;
-    private _UNLIMITED_ALLOWANCE_IN_BASE_UNITS: BigNumber;
     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) {
+    constructor(store: AbstractBalanceAndProxyAllowanceLazyStore) {
-        this._store = new BalanceAndProxyAllowanceLazyStore(token, defaultBlock);
+        this._store = store;
-        this._UNLIMITED_ALLOWANCE_IN_BASE_UNITS = token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
     }
     /**
      * 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));
         }
     }

packages/contract-wrappers/test/exchange_transfer_simulator_test.ts

@@ -5,6 +5,7 @@ import * as chai from 'chai';
 import 'make-promises-safe';
 
 import { ContractWrappers, ExchangeContractErrs } from '../src';
+import { BalanceAndProxyAllowanceLazyStore } from '../src/stores/balance_proxy_allowance_lazy_store';
 import { TradeSide, TransferType } from '../src/types';
 import { ExchangeTransferSimulator } from '../src/utils/exchange_transfer_simulator';
 
@@ -44,7 +45,11 @@ describe('ExchangeTransferSimulator', () => {
     });
     describe('#transferFromAsync', () => {
         beforeEach(() => {
-            exchangeTransferSimulator = new ExchangeTransferSimulator(contractWrappers.token, BlockParamLiteral.Latest);
+            const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+                contractWrappers.token,
+                BlockParamLiteral.Latest,
+            );
+            exchangeTransferSimulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
         });
         it("throws if the user doesn't have enough allowance", async () => {
             return expect(

packages/contract-wrappers/test/order_validation_test.ts

@@ -8,6 +8,7 @@ import 'make-promises-safe';
 import * as Sinon from 'sinon';
 
 import { ContractWrappers, ExchangeContractErrs, SignedOrder, Token } from '../src';
+import { BalanceAndProxyAllowanceLazyStore } from '../src/stores/balance_proxy_allowance_lazy_store';
 import { TradeSide, TransferType } from '../src/types';
 import { ExchangeTransferSimulator } from '../src/utils/exchange_transfer_simulator';
 import { OrderValidationUtils } from '../src/utils/order_validation_utils';
@@ -332,7 +333,11 @@ describe('OrderValidation', () => {
             return Sinon.match((value: BigNumber) => value.eq(expected));
         };
         beforeEach('create exchangeTransferSimulator', async () => {
-            exchangeTransferSimulator = new ExchangeTransferSimulator(contractWrappers.token, BlockParamLiteral.Latest);
+            const balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+                contractWrappers.token,
+                BlockParamLiteral.Latest,
+            );
+            exchangeTransferSimulator = new ExchangeTransferSimulator(balanceAndProxyAllowanceLazyStore);
             transferFromAsync = Sinon.spy();
             exchangeTransferSimulator.transferFromAsync = transferFromAsync as any;
         });