| // Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| library chain_test; |
| |
| import 'dart:async'; |
| |
| import 'package:path/path.dart' as p; |
| import 'package:stack_trace/stack_trace.dart'; |
| import 'package:unittest/unittest.dart'; |
| |
| import 'utils.dart'; |
| |
| void main() { |
| group('capture() with onError catches exceptions', () { |
| test('thrown in a microtask', () { |
| return captureFuture(() => inMicrotask(() => throw 'error')) |
| .then((chain) { |
| // Since there was only one asynchronous operation, there should be only |
| // two traces in the chain. |
| expect(chain.traces, hasLength(2)); |
| |
| // The first frame of the first trace should be the line on which the |
| // actual error was thrown. |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| |
| // The second trace should describe the stack when the error callback |
| // was scheduled. |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| }); |
| }); |
| |
| test('thrown in a one-shot timer', () { |
| return captureFuture(() => inOneShotTimer(() => throw 'error')) |
| .then((chain) { |
| expect(chain.traces, hasLength(2)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inOneShotTimer')))); |
| }); |
| }); |
| |
| test('thrown in a periodic timer', () { |
| return captureFuture(() => inPeriodicTimer(() => throw 'error')) |
| .then((chain) { |
| expect(chain.traces, hasLength(2)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inPeriodicTimer')))); |
| }); |
| }); |
| |
| test('thrown in a nested series of asynchronous operations', () { |
| return captureFuture(() { |
| inPeriodicTimer(() { |
| inOneShotTimer(() => inMicrotask(() => throw 'error')); |
| }); |
| }).then((chain) { |
| expect(chain.traces, hasLength(4)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inOneShotTimer')))); |
| expect(chain.traces[3].frames, |
| contains(frameMember(startsWith('inPeriodicTimer')))); |
| }); |
| }); |
| |
| test('thrown in a long future chain', () { |
| return captureFuture(() => inFutureChain(() => throw 'error')) |
| .then((chain) { |
| // Despite many asynchronous operations, there's only one level of |
| // nested calls, so there should be only two traces in the chain. This |
| // is important; programmers expect stack trace memory consumption to be |
| // O(depth of program), not O(length of program). |
| expect(chain.traces, hasLength(2)); |
| |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inFutureChain')))); |
| }); |
| }); |
| |
| test('multiple times', () { |
| var completer = new Completer(); |
| var first = true; |
| |
| Chain.capture(() { |
| inMicrotask(() => throw 'first error'); |
| inPeriodicTimer(() => throw 'second error'); |
| }, onError: (error, chain) { |
| if (first) { |
| expect(error, equals('first error')); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| first = false; |
| } else { |
| expect(error, equals('second error')); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inPeriodicTimer')))); |
| completer.complete(); |
| } |
| }); |
| |
| return completer.future; |
| }); |
| }); |
| |
| test('capture() without onError passes exceptions to parent zone', () { |
| var completer = new Completer(); |
| |
| runZoned(() { |
| Chain.capture(() => inMicrotask(() => throw 'error')); |
| }, onError: (error, chain) { |
| expect(error, equals('error')); |
| expect(chain, new isInstanceOf<Chain>()); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| completer.complete(); |
| }); |
| |
| return completer.future; |
| }); |
| |
| group('current() within capture()', () { |
| test('called in a microtask', () { |
| var completer = new Completer(); |
| Chain.capture(() { |
| inMicrotask(() => completer.complete(new Chain.current())); |
| }); |
| |
| return completer.future.then((chain) { |
| expect(chain.traces, hasLength(2)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| }); |
| }); |
| |
| test('called in a one-shot timer', () { |
| var completer = new Completer(); |
| Chain.capture(() { |
| inOneShotTimer(() => completer.complete(new Chain.current())); |
| }); |
| |
| return completer.future.then((chain) { |
| expect(chain.traces, hasLength(2)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inOneShotTimer')))); |
| }); |
| }); |
| |
| test('called in a periodic timer', () { |
| var completer = new Completer(); |
| Chain.capture(() { |
| inPeriodicTimer(() => completer.complete(new Chain.current())); |
| }); |
| |
| return completer.future.then((chain) { |
| expect(chain.traces, hasLength(2)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inPeriodicTimer')))); |
| }); |
| }); |
| |
| test('called in a nested series of asynchronous operations', () { |
| var completer = new Completer(); |
| Chain.capture(() { |
| inPeriodicTimer(() { |
| inOneShotTimer(() { |
| inMicrotask(() => completer.complete(new Chain.current())); |
| }); |
| }); |
| }); |
| |
| return completer.future.then((chain) { |
| expect(chain.traces, hasLength(4)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inOneShotTimer')))); |
| expect(chain.traces[3].frames, |
| contains(frameMember(startsWith('inPeriodicTimer')))); |
| }); |
| }); |
| |
| test('called in a long future chain', () { |
| var completer = new Completer(); |
| Chain.capture(() { |
| inFutureChain(() => completer.complete(new Chain.current())); |
| }); |
| |
| return completer.future.then((chain) { |
| expect(chain.traces, hasLength(2)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('inFutureChain')))); |
| }); |
| }); |
| }); |
| |
| test('current() outside of capture() returns a chain wrapping the current ' |
| 'trace', () { |
| var completer = new Completer(); |
| inMicrotask(() => completer.complete(new Chain.current())); |
| |
| return completer.future.then((chain) { |
| // Since the chain wasn't loaded within [Chain.capture], the full stack |
| // chain isn't available and it just returns the current stack when |
| // called. |
| expect(chain.traces, hasLength(1)); |
| expect(chain.traces.first.frames.first, frameMember(startsWith('main'))); |
| }); |
| }); |
| |
| group('forTrace() within capture()', () { |
| test('called for a stack trace from a microtask', () { |
| return Chain.capture(() { |
| return chainForTrace(inMicrotask, () => throw 'error'); |
| }).then((chain) { |
| // Because [chainForTrace] has to set up a future chain to capture the |
| // stack trace while still showing it to the zone specification, it adds |
| // an additional level of async nesting and so an additional trace. |
| expect(chain.traces, hasLength(3)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('chainForTrace')))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| }); |
| }); |
| |
| test('called for a stack trace from a one-shot timer', () { |
| return Chain.capture(() { |
| return chainForTrace(inOneShotTimer, () => throw 'error'); |
| }).then((chain) { |
| expect(chain.traces, hasLength(3)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('chainForTrace')))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inOneShotTimer')))); |
| }); |
| }); |
| |
| test('called for a stack trace from a periodic timer', () { |
| return Chain.capture(() { |
| return chainForTrace(inPeriodicTimer, () => throw 'error'); |
| }).then((chain) { |
| expect(chain.traces, hasLength(3)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('chainForTrace')))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inPeriodicTimer')))); |
| }); |
| }); |
| |
| test('called for a stack trace from a nested series of asynchronous ' |
| 'operations', () { |
| return Chain.capture(() { |
| return chainForTrace((callback) { |
| inPeriodicTimer(() => inOneShotTimer(() => inMicrotask(callback))); |
| }, () => throw 'error'); |
| }).then((chain) { |
| expect(chain.traces, hasLength(5)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('chainForTrace')))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| expect(chain.traces[3].frames, |
| contains(frameMember(startsWith('inOneShotTimer')))); |
| expect(chain.traces[4].frames, |
| contains(frameMember(startsWith('inPeriodicTimer')))); |
| }); |
| }); |
| |
| test('called for a stack trace from a long future chain', () { |
| return Chain.capture(() { |
| return chainForTrace(inFutureChain, () => throw 'error'); |
| }).then((chain) { |
| expect(chain.traces, hasLength(3)); |
| expect(chain.traces[0].frames.first, frameMember(startsWith('main'))); |
| expect(chain.traces[1].frames, |
| contains(frameMember(startsWith('chainForTrace')))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inFutureChain')))); |
| }); |
| }); |
| |
| test('called for an unregistered stack trace returns a chain wrapping that ' |
| 'trace', () { |
| var trace; |
| var chain = Chain.capture(() { |
| try { |
| throw 'error'; |
| } catch (_, stackTrace) { |
| trace = stackTrace; |
| return new Chain.forTrace(stackTrace); |
| } |
| }); |
| |
| expect(chain.traces, hasLength(1)); |
| expect(chain.traces.first.toString(), |
| equals(new Trace.from(trace).toString())); |
| }); |
| }); |
| |
| test('forTrace() outside of capture() returns a chain wrapping the given ' |
| 'trace', () { |
| var trace; |
| var chain = Chain.capture(() { |
| try { |
| throw 'error'; |
| } catch (_, stackTrace) { |
| trace = stackTrace; |
| return new Chain.forTrace(stackTrace); |
| } |
| }); |
| |
| expect(chain.traces, hasLength(1)); |
| expect(chain.traces.first.toString(), |
| equals(new Trace.from(trace).toString())); |
| }); |
| |
| test('Chain.parse() parses a real Chain', () { |
| return captureFuture(() => inMicrotask(() => throw 'error')).then((chain) { |
| expect(new Chain.parse(chain.toString()).toString(), |
| equals(chain.toString())); |
| }); |
| }); |
| |
| var userSlashCode = p.join('user', 'code.dart'); |
| group('Chain.terse', () { |
| test('makes each trace terse', () { |
| var chain = new Chain([ |
| new Trace.parse( |
| 'dart:core 10:11 Foo.bar\n' |
| 'dart:core 10:11 Bar.baz\n' |
| 'user/code.dart 10:11 Bang.qux\n' |
| 'dart:core 10:11 Zip.zap\n' |
| 'dart:core 10:11 Zop.zoop'), |
| new Trace.parse( |
| 'user/code.dart 10:11 Bang.qux\n' |
| 'dart:core 10:11 Foo.bar\n' |
| 'package:stack_trace/stack_trace.dart 10:11 Bar.baz\n' |
| 'dart:core 10:11 Zip.zap\n' |
| 'user/code.dart 10:11 Zop.zoop') |
| ]); |
| |
| expect(chain.terse.toString(), equals( |
| 'dart:core Bar.baz\n' |
| '$userSlashCode 10:11 Bang.qux\n' |
| 'dart:core Zop.zoop\n' |
| '===== asynchronous gap ===========================\n' |
| '$userSlashCode 10:11 Bang.qux\n' |
| 'dart:core Zip.zap\n' |
| '$userSlashCode 10:11 Zop.zoop\n')); |
| }); |
| |
| test('eliminates internal-only traces', () { |
| var chain = new Chain([ |
| new Trace.parse( |
| 'user/code.dart 10:11 Foo.bar\n' |
| 'dart:core 10:11 Bar.baz'), |
| new Trace.parse( |
| 'dart:core 10:11 Foo.bar\n' |
| 'package:stack_trace/stack_trace.dart 10:11 Bar.baz\n' |
| 'dart:core 10:11 Zip.zap'), |
| new Trace.parse( |
| 'user/code.dart 10:11 Foo.bar\n' |
| 'dart:core 10:11 Bar.baz') |
| ]); |
| |
| expect(chain.terse.toString(), equals( |
| '$userSlashCode 10:11 Foo.bar\n' |
| 'dart:core Bar.baz\n' |
| '===== asynchronous gap ===========================\n' |
| '$userSlashCode 10:11 Foo.bar\n' |
| 'dart:core Bar.baz\n')); |
| }); |
| |
| test("doesn't return an empty chain", () { |
| var chain = new Chain([ |
| new Trace.parse( |
| 'dart:core 10:11 Foo.bar\n' |
| 'package:stack_trace/stack_trace.dart 10:11 Bar.baz\n' |
| 'dart:core 10:11 Zip.zap'), |
| new Trace.parse( |
| 'dart:core 10:11 A.b\n' |
| 'package:stack_trace/stack_trace.dart 10:11 C.d\n' |
| 'dart:core 10:11 E.f') |
| ]); |
| |
| expect(chain.terse.toString(), equals('dart:core E.f\n')); |
| }); |
| }); |
| |
| group('Chain.foldFrames', () { |
| test('folds each trace', () { |
| var chain = new Chain([ |
| new Trace.parse( |
| 'a.dart 10:11 Foo.bar\n' |
| 'a.dart 10:11 Bar.baz\n' |
| 'b.dart 10:11 Bang.qux\n' |
| 'a.dart 10:11 Zip.zap\n' |
| 'a.dart 10:11 Zop.zoop'), |
| new Trace.parse( |
| 'a.dart 10:11 Foo.bar\n' |
| 'a.dart 10:11 Bar.baz\n' |
| 'a.dart 10:11 Bang.qux\n' |
| 'a.dart 10:11 Zip.zap\n' |
| 'b.dart 10:11 Zop.zoop') |
| ]); |
| |
| var folded = chain.foldFrames((frame) => frame.library == 'a.dart'); |
| expect(folded.toString(), equals( |
| 'a.dart 10:11 Bar.baz\n' |
| 'b.dart 10:11 Bang.qux\n' |
| 'a.dart 10:11 Zop.zoop\n' |
| '===== asynchronous gap ===========================\n' |
| 'a.dart 10:11 Zip.zap\n' |
| 'b.dart 10:11 Zop.zoop\n')); |
| }); |
| |
| test('eliminates completely-folded traces', () { |
| var chain = new Chain([ |
| new Trace.parse( |
| 'a.dart 10:11 Foo.bar\n' |
| 'b.dart 10:11 Bang.qux'), |
| new Trace.parse( |
| 'a.dart 10:11 Foo.bar\n' |
| 'a.dart 10:11 Bang.qux'), |
| new Trace.parse( |
| 'a.dart 10:11 Zip.zap\n' |
| 'b.dart 10:11 Zop.zoop') |
| ]); |
| |
| var folded = chain.foldFrames((frame) => frame.library == 'a.dart'); |
| expect(folded.toString(), equals( |
| 'a.dart 10:11 Foo.bar\n' |
| 'b.dart 10:11 Bang.qux\n' |
| '===== asynchronous gap ===========================\n' |
| 'a.dart 10:11 Zip.zap\n' |
| 'b.dart 10:11 Zop.zoop\n')); |
| }); |
| |
| test("doesn't return an empty trace", () { |
| var chain = new Chain([ |
| new Trace.parse( |
| 'a.dart 10:11 Foo.bar\n' |
| 'a.dart 10:11 Bang.qux') |
| ]); |
| |
| var folded = chain.foldFrames((frame) => frame.library == 'a.dart'); |
| expect(folded.toString(), equals('a.dart 10:11 Bang.qux\n')); |
| }); |
| }); |
| |
| test('Chain.toTrace eliminates asynchronous gaps', () { |
| var trace = new Chain([ |
| new Trace.parse( |
| 'user/code.dart 10:11 Foo.bar\n' |
| 'dart:core 10:11 Bar.baz'), |
| new Trace.parse( |
| 'user/code.dart 10:11 Foo.bar\n' |
| 'dart:core 10:11 Bar.baz') |
| ]).toTrace(); |
| |
| expect(trace.toString(), equals( |
| '$userSlashCode 10:11 Foo.bar\n' |
| 'dart:core 10:11 Bar.baz\n' |
| '$userSlashCode 10:11 Foo.bar\n' |
| 'dart:core 10:11 Bar.baz\n')); |
| }); |
| |
| group('Chain.track(Future)', () { |
| test('associates the current chain with a manually-reported exception with ' |
| 'a stack trace', () { |
| var trace = new Trace.current(); |
| return captureFuture(() { |
| inMicrotask(() => trackedErrorFuture(trace)); |
| }).then((chain) { |
| expect(chain.traces, hasLength(3)); |
| |
| // The first trace is the trace that was manually reported for the |
| // error. |
| expect(chain.traces.first.toString(), equals(trace.toString())); |
| |
| // The second trace is the trace that was captured when [Chain.track] |
| // was called. |
| expect(chain.traces[1].frames.first, |
| frameMember(startsWith('trackedErrorFuture'))); |
| |
| // The third trace is the automatically-captured trace from when the |
| // microtask was scheduled. |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| }); |
| }); |
| |
| test('associates the current chain with a manually-reported exception with ' |
| 'no stack trace', () { |
| return captureFuture(() { |
| inMicrotask(() => trackedErrorFuture()); |
| }).then((chain) { |
| expect(chain.traces, hasLength(3)); |
| |
| // The first trace is the one captured by |
| // [StackZoneSpecification.trackFuture], which should contain only |
| // stack_trace and dart: frames. |
| expect(chain.traces.first.frames, |
| everyElement(frameLibrary(isNot(contains('chain_test'))))); |
| |
| expect(chain.traces[1].frames.first, |
| frameMember(startsWith('trackedErrorFuture'))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| }); |
| }); |
| |
| test('forwards the future value within Chain.capture()', () { |
| Chain.capture(() { |
| expect(Chain.track(new Future.value('value')), |
| completion(equals('value'))); |
| |
| var trace = new Trace.current(); |
| expect(Chain.track(new Future.error('error', trace)) |
| .catchError((e, stackTrace) { |
| expect(e, equals('error')); |
| expect(stackTrace.toString(), equals(trace.toString())); |
| }), completes); |
| }); |
| }); |
| |
| test('forwards the future value outside of Chain.capture()', () { |
| expect(Chain.track(new Future.value('value')), |
| completion(equals('value'))); |
| |
| var trace = new Trace.current(); |
| expect(Chain.track(new Future.error('error', trace)) |
| .catchError((e, stackTrace) { |
| expect(e, equals('error')); |
| expect(stackTrace.toString(), equals(trace.toString())); |
| }), completes); |
| }); |
| }); |
| |
| group('Chain.track(Stream)', () { |
| test('associates the current chain with a manually-reported exception with ' |
| 'a stack trace', () { |
| var trace = new Trace.current(); |
| return captureFuture(() { |
| inMicrotask(() => trackedErrorStream(trace).listen(null)); |
| }).then((chain) { |
| expect(chain.traces, hasLength(3)); |
| expect(chain.traces.first.toString(), equals(trace.toString())); |
| expect(chain.traces[1].frames.first, |
| frameMember(startsWith('trackedErrorStream'))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| }); |
| }); |
| |
| test('associates the current chain with a manually-reported exception with ' |
| 'no stack trace', () { |
| return captureFuture(() { |
| inMicrotask(() => trackedErrorStream().listen(null)); |
| }).then((chain) { |
| expect(chain.traces, hasLength(3)); |
| expect(chain.traces.first.frames, |
| everyElement(frameLibrary(isNot(contains('chain_test'))))); |
| expect(chain.traces[1].frames.first, |
| frameMember(startsWith('trackedErrorStream'))); |
| expect(chain.traces[2].frames, |
| contains(frameMember(startsWith('inMicrotask')))); |
| }); |
| }); |
| |
| test('forwards stream values within Chain.capture()', () { |
| Chain.capture(() { |
| var controller = new StreamController() |
| ..add(1)..add(2)..add(3)..close(); |
| expect(Chain.track(controller.stream).toList(), |
| completion(equals([1, 2, 3]))); |
| |
| var trace = new Trace.current(); |
| controller = new StreamController()..addError('error', trace); |
| expect(Chain.track(controller.stream).toList() |
| .catchError((e, stackTrace) { |
| expect(e, equals('error')); |
| expect(stackTrace.toString(), equals(trace.toString())); |
| }), completes); |
| }); |
| }); |
| |
| test('forwards stream values outside of Chain.capture()', () { |
| Chain.capture(() { |
| var controller = new StreamController() |
| ..add(1)..add(2)..add(3)..close(); |
| expect(Chain.track(controller.stream).toList(), |
| completion(equals([1, 2, 3]))); |
| |
| var trace = new Trace.current(); |
| controller = new StreamController()..addError('error', trace); |
| expect(Chain.track(controller.stream).toList() |
| .catchError((e, stackTrace) { |
| expect(e, equals('error')); |
| expect(stackTrace.toString(), equals(trace.toString())); |
| }), completes); |
| }); |
| }); |
| }); |
| } |
| |
| /// Runs [callback] in a microtask callback. |
| void inMicrotask(callback()) => scheduleMicrotask(callback); |
| |
| /// Runs [callback] in a one-shot timer callback. |
| void inOneShotTimer(callback()) => Timer.run(callback); |
| |
| /// Runs [callback] once in a periodic timer callback. |
| void inPeriodicTimer(callback()) { |
| var count = 0; |
| new Timer.periodic(new Duration(milliseconds: 1), (timer) { |
| count++; |
| if (count != 5) return; |
| timer.cancel(); |
| callback(); |
| }); |
| } |
| |
| /// Runs [callback] within a long asynchronous Future chain. |
| void inFutureChain(callback()) { |
| new Future(() {}) |
| .then((_) => new Future(() {})) |
| .then((_) => new Future(() {})) |
| .then((_) => new Future(() {})) |
| .then((_) => new Future(() {})) |
| .then((_) => callback()) |
| .then((_) => new Future(() {})); |
| } |
| |
| /// Returns a Future that completes to an error and is wrapped in [Chain.track]. |
| /// |
| /// If [trace] is passed, it's used as the stack trace for the error. |
| Future trackedErrorFuture([StackTrace trace]) { |
| var completer = new Completer(); |
| completer.completeError('error', trace); |
| return Chain.track(completer.future); |
| } |
| |
| /// Returns a Stream that emits an error and is wrapped in [Chain.track]. |
| /// |
| /// If [trace] is passed, it's used as the stack trace for the error. |
| Stream trackedErrorStream([StackTrace trace]) { |
| var controller = new StreamController(); |
| controller.addError('error', trace); |
| return Chain.track(controller.stream); |
| } |
| |
| /// Runs [callback] within [asyncFn], then converts any errors raised into a |
| /// [Chain] with [Chain.forTrace]. |
| Future<Chain> chainForTrace(asyncFn(callback()), callback()) { |
| var completer = new Completer(); |
| asyncFn(() { |
| // We use `new Future.value().then(...)` here as opposed to [new Future] or |
| // [new Future.sync] because those methods don't pass the exception through |
| // the zone specification before propagating it, so there's no chance to |
| // attach a chain to its stack trace. See issue 15105. |
| new Future.value().then((_) => callback()) |
| .catchError(completer.completeError); |
| }); |
| return completer.future |
| .catchError((_, stackTrace) => new Chain.forTrace(stackTrace)); |
| } |
| |
| /// Runs [callback] in a [Chain.capture] zone and returns a Future that |
| /// completes to the stack chain for an error thrown by [callback]. |
| /// |
| /// [callback] is expected to throw the string `"error"`. |
| Future<Chain> captureFuture(callback()) { |
| var completer = new Completer<Chain>(); |
| Chain.capture(callback, onError: (error, chain) { |
| expect(error, equals('error')); |
| completer.complete(chain); |
| }); |
| return completer.future; |
| } |