1 files changed, 4 insertions, 18 deletions
diff --git a/packages/0x.js/test/subscription_test.ts b/packages/0x.js/test/subscription_test.ts
index d6269f15f..f4c6f748f 100644
--- a/packages/0x.js/test/subscription_test.ts
+++ b/packages/0x.js/test/subscription_test.ts
@@ -1,6 +1,5 @@
 import { BlockchainLifecycle } from '@0xproject/dev-utils';
 import { BigNumber } from '@0xproject/utils';
-import * as chai from 'chai';
 import * as _ from 'lodash';
 import 'mocha';
 import * as Sinon from 'sinon';
@@ -11,11 +10,10 @@ import { DoneCallback } from '../src/types';
 
 import { chaiSetup } from './utils/chai_setup';
 import { constants } from './utils/constants';
-import { reportCallbackErrors } from './utils/report_callback_errors';
+import { assertNodeCallbackError } from './utils/report_callback_errors';
 import { web3Factory } from './utils/web3_factory';
 
 chaiSetup.configure();
-const expect = chai.expect;
 const blockchainLifecycle = new BlockchainLifecycle(constants.RPC_URL);
 
 describe('SubscriptionTest', () => {
@@ -59,13 +57,7 @@ describe('SubscriptionTest', () => {
         it('Should receive the Error when an error occurs while fetching the block', (done: DoneCallback) => {
             (async () => {
                 const errMsg = 'Error fetching block';
-                const callback = reportCallbackErrors(done)(
-                    (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
-                        expect(err.message).to.be.equal(errMsg);
-                        expect(logEvent).to.be.undefined();
-                        done();
-                    },
-                );
+                const callback = assertNodeCallbackError(done, errMsg);
                 stubs = [Sinon.stub((zeroEx as any)._web3Wrapper, 'getBlockAsync').throws(new Error(errMsg))];
                 zeroEx.token.subscribe(tokenAddress, TokenEvents.Approval, indexFilterValues, callback);
                 await zeroEx.token.setAllowanceAsync(tokenAddress, coinbase, addressWithoutFunds, allowanceAmount);
@@ -74,13 +66,7 @@ describe('SubscriptionTest', () => {
         it('Should receive the Error when an error occurs while reconciling the new block', (done: DoneCallback) => {
             (async () => {
                 const errMsg = 'Error fetching logs';
-                const callback = reportCallbackErrors(done)(
-                    (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
-                        expect(err.message).to.be.equal(errMsg);
-                        expect(logEvent).to.be.undefined();
-                        done();
-                    },
-                );
+                const callback = assertNodeCallbackError(done, errMsg);
                 stubs = [Sinon.stub((zeroEx as any)._web3Wrapper, 'getLogsAsync').throws(new Error(errMsg))];
                 zeroEx.token.subscribe(tokenAddress, TokenEvents.Approval, indexFilterValues, callback);
                 await zeroEx.token.setAllowanceAsync(tokenAddress, coinbase, addressWithoutFunds, allowanceAmount);
@@ -88,7 +74,7 @@ describe('SubscriptionTest', () => {
         });
         it('Should allow unsubscribeAll to be called successfully after an error', (done: DoneCallback) => {
             (async () => {
-                const callback = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => _.noop;
+                const callback = (err: Error | null, logEvent?: DecodedLogEvent<ApprovalContractEventArgs>) => _.noop;
                 zeroEx.token.subscribe(tokenAddress, TokenEvents.Approval, indexFilterValues, callback);
                 stubs = [Sinon.stub((zeroEx as any)._web3Wrapper, 'getBlockAsync').throws(new Error('JSON RPC error'))];
                 zeroEx.token.unsubscribeAll();