Errors thrown from a Mock are not caught as expected

[DartBot]

Originally opened as dart-lang/sdk#19098

This issue was originally filed by da...@google.com

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What steps will reproduce the problem?

mockbug.dart:

import 'dart:async';

import 'package:unittest/unittest.dart'; import 'package:mock/mock.dart';

void main() {   test("Function", () {     Future doStuff() {       return new Future.error(new StateError("AAAAH!"));     }

    return new Future(() {       return doStuff().then((_) {         fail("Expected an error!");       }).catchError((e) {         expect(e, isStateError);       });     }).catchError((e) {       print("Outside caught: $e");     });   });

  test("Mock", () {     Mock m = new Mock();     m.when(callsTo("doStuff")).thenReturn(         new Future.error(new StateError("AAAAH!")));

    return new Future(() {       return m.doStuff().then((_) {         fail("Expected an error!");       }).catchError((e) {         expect(e, isStateError);       });     }).catchError((e) {       print("Outside caught: $e");     });   }); }

Expected output:

PASS: Function PASS: Mock

Actual output:

PASS: Function FAIL: Mock   Caught Bad state: AAAAH!

Dart Editor 1.5.0dev_01_02 Dart SDK 1.5.0dev.1.2

This works fine with a simpler code structure (i.e.: without the enclosing Future, for example). Unfortunately, the actual code that this minimal example is based on uses this structure.

[DartBot]

Comment by sethladd

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Added Pkg-mock, Area-Pkg, Triaged labels.