Fix expectedAmountAvailableToFill test

packages/asset-buyer/test/buy_quote_calculator_test.ts

@@ -168,7 +168,7 @@ describe('buyQuoteCalculator', () => {
                 };
                 testHelpers.expectInsufficientLiquidityError(expect, errorFunction, new BigNumber(1));
             });
-            it('should throw without amount available to fill if amount rounds to 0', () => {
+            it('should throw with 0 available to fill if amount rounds to 0', () => {
                 const smallOrder = orderFactory.createSignedOrderFromPartial({
                     makerAssetAmount: new BigNumber(1),
                     takerAssetAmount: new BigNumber(1),
@@ -184,7 +184,7 @@ describe('buyQuoteCalculator', () => {
                         false,
                     );
                 };
-                testHelpers.expectInsufficientLiquidityError(expect, errorFunction, undefined);
+                testHelpers.expectInsufficientLiquidityError(expect, errorFunction, new BigNumber(0));
             });
         });
         it('should not throw if order is fillable', () => {

packages/asset-buyer/test/utils/test_helpers.ts

@@ -6,7 +6,7 @@ export const testHelpers = {
     expectInsufficientLiquidityError: (
         expect: Chai.ExpectStatic,
         functionWhichTriggersError: () => void,
-        expectedAmountAvailableToFill?: BigNumber,
+        expectedAmountAvailableToFill: BigNumber,
     ): void => {
         let wasErrorThrown = false;
         try {