Add getOrderHashHexUsingContractCallAsync

2 files changed, 28 insertions, 0 deletions

diff --git a/src/contract_wrappers/exchange_wrapper.ts b/src/contract_wrappers/exchange_wrapper.ts
index d144d8aad..9cb2332fe 100644
--- a/src/contract_wrappers/exchange_wrapper.ts
+++ b/src/contract_wrappers/exchange_wrapper.ts
@@ -342,6 +342,12 @@ export class ExchangeWrapper extends ContractWrapper {
         const orderHashHex = utils.getOrderHashHex(order, exchangeInstance.address);
         return orderHashHex;
     }
+    private async getOrderHashHexUsingContractCallAsync(order: Order|SignedOrder): Promise<string> {
+        const exchangeInstance = await this.getExchangeContractAsync();
+        const [orderAddresses, orderValues] = ExchangeWrapper.getOrderAddressesAndValues(order);
+        const orderHashHex = await exchangeInstance.getOrderHash.call(orderAddresses, orderValues);
+        return orderHashHex;
+    }
     private async stopWatchingExchangeLogEventsAsync() {
         const stopWatchingPromises = _.map(this.exchangeLogEventObjs, logEventObj => {
             return promisify(logEventObj.stopWatching, logEventObj)();
diff --git a/test/exchange_wrapper_test.ts b/test/exchange_wrapper_test.ts
index 08936f1d2..6fef91946 100644
--- a/test/exchange_wrapper_test.ts
+++ b/test/exchange_wrapper_test.ts
@@ -661,4 +661,26 @@ describe('ExchangeWrapper', () => {
             })();
         });
     });
+    describe('#getOrderHashHexUsingContractCallAsync', () => {
+        let makerTokenAddress: string;
+        let takerTokenAddress: string;
+        let makerAddress: string;
+        let takerAddress: string;
+        const fillableAmount = new BigNumber(5);
+        before(async () => {
+            [, makerAddress, takerAddress] = userAddresses;
+            const [makerToken, takerToken] = tokenUtils.getNonProtocolTokens();
+            makerTokenAddress = makerToken.address;
+            takerTokenAddress = takerToken.address;
+        });
+        it('get\'s the same hash as the local function', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            const orderHash = await zeroEx.getOrderHashHexAsync(signedOrder);
+            const orderHashFromContract = await (zeroEx.exchange as any)
+                .getOrderHashHexUsingContractCallAsync(signedOrder);
+            expect(orderHash).to.equal(orderHashFromContract);
+        });
+    });
 });