Revert "[dart:io] Adds waitForEventSync"

This reverts commit 2aed87a133.

Reverting for failures on precompiled bots.

Change-Id: I758bfc72d8f5e67b0e5e12a7367a47f1df9364e2
Reviewed-on: https://dart-review.googlesource.com/28900
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Zach Anderson <zra@google.com>

runtime/bin/common.cc

@@ -1,27 +0,0 @@
-// Copyright (c) 2017, 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.
-
-#include "bin/builtin.h"
-#include "bin/dartutils.h"
-
-#include "include/dart_api.h"
-
-namespace dart {
-namespace bin {
-
-void FUNCTION_NAME(IOUtils_WaitForEventSync)(Dart_NativeArguments args) {
-  int64_t timeout_millis;
-  Dart_Handle result = Dart_GetNativeIntegerArgument(args, 0, &timeout_millis);
-  if (Dart_IsError(result)) {
-    Dart_PropagateError(result);
-  }
-  result = Dart_WaitForEventSync(timeout_millis);
-  if (Dart_IsError(result)) {
-    Dart_PropagateError(result);
-  }
-  Dart_SetReturnValue(args, result);
-}
-
-}  // namespace bin
-}  // namespace dart

runtime/bin/common_patch.dart

@@ -59,13 +59,3 @@ _setupHooks() {
   VMLibraryHooks.eventHandlerSendData = _EventHandler._sendData;
   VMLibraryHooks.timerMillisecondClock = _EventHandler._timerMillisecondClock;
 }
-
-// The implementation of waitForEventSync for embedders in which the VM
-// manages the event loop and microtask queue.
-// IOUtils_WaitForEventSync throws an exception if there is an error.
-void _standaloneWaitForEventSync(int timeoutMillis)
-    native "IOUtils_WaitForEventSync";
-
-void Function(int timeoutMillis) _getWaitForEventSyncClosure() {
-  return _standaloneWaitForEventSync;
-}

runtime/bin/dartutils.cc

@@ -572,12 +572,6 @@ Dart_Handle DartUtils::SetupIOLibrary(const char* namespc_path,
   Dart_Handle set_script_name =
       Dart_SetField(platform_type, script_name, dart_script);
   RETURN_IF_ERROR(set_script_name);
-
-  Dart_Handle wait_for_event =
-      Dart_Invoke(io_lib, NewString("_getWaitForEventSyncClosure"), 0, NULL);
-  RETURN_IF_ERROR(wait_for_event);
-  RETURN_IF_ERROR(Dart_SetField(io_lib, NewString("_waitForEventSyncImpl"),
-                                wait_for_event));
   return Dart_Null();
 }
 

runtime/bin/io_impl_sources.gni

@@ -5,7 +5,6 @@
 # This file contains some C++ sources for the dart:io library.  The other
 # implementation files are in builtin_impl_sources.gypi.
 io_impl_sources = [
-  "common.cc",
   "eventhandler.cc",
   "eventhandler.h",
   "eventhandler_android.cc",

runtime/bin/io_natives.cc

@@ -81,7 +81,6 @@ namespace bin {
   V(Filter_Processed, 3)                                                       \
   V(InternetAddress_Parse, 1)                                                  \
   V(IOService_NewServicePort, 0)                                               \
-  V(IOUtils_WaitForEventSync, 1)                                               \
   V(Namespace_Create, 2)                                                       \
   V(Namespace_GetDefault, 0)                                                   \
   V(Namespace_GetPointer, 1)                                                   \

runtime/bin/main.cc

@@ -676,8 +676,6 @@ static Dart_QualifiedFunctionName standalone_entry_points[] = {
     {"dart:io", "::", "_makeDatagram"},
     {"dart:io", "::", "_makeUint8ListView"},
     {"dart:io", "::", "_setupHooks"},
-    {"dart:io", "::", "_getWaitForEventSyncClosure"},
-    {"dart:io", "::", "_waitForEventSyncImpl"},
     {"dart:io", "_EmbedderConfig", "_mayExit"},
     {"dart:io", "_ExternalBuffer", "get:end"},
     {"dart:io", "_ExternalBuffer", "get:start"},

runtime/include/dart_api.h

@@ -1215,16 +1215,6 @@ DART_EXPORT Dart_Handle Dart_HandleMessage();
  */
 DART_EXPORT Dart_Handle Dart_HandleMessages();
 
-/**
- * Drains the microtask queue, then blocks the calling thread until the current
- * isolate recieves a message, then handles all messages.
- *
- * \param timeout_millis When non-zero, the call returns after the indicated
-          number of milliseconds even if no message was received.
- * \return A valid handle if no error occurs, otherwise an error handle.
- */
-DART_EXPORT Dart_Handle Dart_WaitForEventSync(int64_t timeout_millis);
-
 /**
  * Handles any pending messages for the vm service for the current
  * isolate.

runtime/lib/isolate_patch.dart

@@ -100,8 +100,7 @@ _ImmediateCallback _pendingImmediateCallback;
 /// The closure that should be used as scheduleImmediateClosure, when the VM
 /// is responsible for the event loop.
 void _isolateScheduleImmediate(void callback()) {
-  assert((_pendingImmediateCallback == null) ||
-      (_pendingImmediateCallback == callback));
+  assert(_pendingImmediateCallback == null);
   _pendingImmediateCallback = callback;
 }
 

runtime/lib/schedule_microtask_patch.dart

@@ -24,7 +24,3 @@ class _ScheduleImmediate {
 void _setScheduleImmediateClosure(_ScheduleImmediateClosure closure) {
   _ScheduleImmediate._closure = closure;
 }
-
-void _ensureScheduleImmediate() {
-  _AsyncRun._scheduleImmediate(_startMicrotaskLoop);
-}

runtime/vm/dart_api_impl.cc

@@ -1672,36 +1672,6 @@ DART_EXPORT Dart_Handle Dart_HandleMessages() {
   return Api::Success();
 }
 
-DART_EXPORT Dart_Handle Dart_WaitForEventSync(int64_t timeout_millis) {
-  Thread* T = Thread::Current();
-  Isolate* I = T->isolate();
-  CHECK_API_SCOPE(T);
-  CHECK_CALLBACK_STATE(T);
-  API_TIMELINE_BEGIN_END_BASIC;
-  TransitionNativeToVM transition(T);
-  if (I->message_notify_callback() != NULL) {
-    return Api::NewError("waitForEventSync is not supported by this embedder");
-  }
-  // NB: If waitForEventSync() is moved from dart:io to dart:async, then
-  // this call can be made from Dart code instead of from the runtime.
-  Object& result =
-      Object::Handle(Z, DartLibraryCalls::EnsureScheduleImmediate());
-  if (result.IsError()) {
-    return Api::NewHandle(T, result.raw());
-  }
-  result = DartLibraryCalls::DrainMicrotaskQueue();
-  if (result.IsError()) {
-    return Api::NewHandle(T, result.raw());
-  }
-  if (I->message_handler()->PauseAndHandleAllMessages(timeout_millis) !=
-      MessageHandler::kOK) {
-    Dart_Handle error = Api::NewHandle(T, T->sticky_error());
-    T->clear_sticky_error();
-    return error;
-  }
-  return Api::Success();
-}
-
 DART_EXPORT bool Dart_HandleServiceMessages() {
 #if defined(PRODUCT)
   return true;

runtime/vm/dart_entry.cc

@@ -665,20 +665,6 @@ RawObject* DartLibraryCalls::DrainMicrotaskQueue() {
   return result.raw();
 }
 
-RawObject* DartLibraryCalls::EnsureScheduleImmediate() {
-  Zone* zone = Thread::Current()->zone();
-  const Library& async_lib = Library::Handle(zone, Library::AsyncLibrary());
-  ASSERT(!async_lib.IsNull());
-  const Function& function =
-      Function::Handle(zone, async_lib.LookupFunctionAllowPrivate(
-                                 Symbols::_ensureScheduleImmediate()));
-  ASSERT(!function.IsNull());
-  const Object& result = Object::Handle(
-      zone, DartEntry::InvokeFunction(function, Object::empty_array()));
-  ASSERT(result.IsNull() || result.IsError());
-  return result.raw();
-}
-
 RawObject* DartLibraryCalls::MapSetAt(const Instance& map,
                                       const Instance& key,
                                       const Instance& value) {

runtime/vm/dart_entry.h

@@ -282,11 +282,6 @@ class DartLibraryCalls : public AllStatic {
   // Returns null on success, a RawError on failure.
   static RawObject* DrainMicrotaskQueue();
 
-  // Ensures that the isolate's _pendingImmediateCallback is set to
-  // _startMicrotaskLoop from dart:async.
-  // Returns null on success, a RawError on failure.
-  static RawObject* EnsureScheduleImmediate();
-
   // map[key] = value;
   //
   // Returns null on success, a RawError on failure.

runtime/vm/message_handler.cc

@@ -54,7 +54,6 @@ MessageHandler::MessageHandler()
     : queue_(new MessageQueue()),
       oob_queue_(new MessageQueue()),
       oob_message_handling_allowed_(true),
-      paused_for_messages_(false),
       live_ports_(0),
       paused_(0),
 #if !defined(PRODUCT)
@@ -152,9 +151,6 @@ void MessageHandler::PostMessage(Message* message, bool before_events) {
     } else {
       queue_->Enqueue(message, before_events);
     }
-    if (paused_for_messages_) {
-      ml.Notify();
-    }
     message = NULL;  // Do not access message.  May have been deleted.
 
     if ((pool_ != NULL) && (task_ == NULL)) {
@@ -280,37 +276,6 @@ MessageHandler::MessageStatus MessageHandler::HandleAllMessages() {
   return HandleMessages(&ml, true, true);
 }
 
-MessageHandler::MessageStatus MessageHandler::PauseAndHandleAllMessages(
-    int64_t timeout_millis) {
-  MonitorLocker ml(&monitor_);
-  ASSERT(task_ != NULL);
-  ASSERT(!delete_me_);
-#if defined(DEBUG)
-  CheckAccess();
-#endif
-  paused_for_messages_ = true;
-  while (queue_->IsEmpty() && oob_queue_->IsEmpty()) {
-    Monitor::WaitResult wr = ml.Wait(timeout_millis);
-    ASSERT(task_ != NULL);
-    ASSERT(!delete_me_);
-    if (wr == Monitor::kTimedOut) {
-      paused_for_messages_ = false;
-      return kOK;
-    }
-    if (queue_->IsEmpty()) {
-      // There are only OOB messages. Handle them and then continue waiting for
-      // normal messages unless there is an error.
-      MessageStatus status = HandleMessages(&ml, false, false);
-      if (status != kOK) {
-        paused_for_messages_ = false;
-        return status;
-      }
-    }
-  }
-  paused_for_messages_ = false;
-  return HandleMessages(&ml, true, true);
-}
-
 MessageHandler::MessageStatus MessageHandler::HandleOOBMessages() {
   if (!oob_message_handling_allowed_) {
     return kOK;

runtime/vm/message_handler.h

@@ -70,10 +70,6 @@ class MessageHandler {
   // Returns true on success.
   MessageStatus HandleOOBMessages();
 
-  // Blocks the thread on a condition variable until a message arrives, and then
-  // handles all messages.
-  MessageStatus PauseAndHandleAllMessages(int64_t timeout_millis);
-
   // Returns true if there are pending OOB messages for this message
   // handler.
   bool HasOOBMessages();
@@ -236,7 +232,6 @@ class MessageHandler {
   // This flag is not thread safe and can only reliably be accessed on a single
   // thread.
   bool oob_message_handling_allowed_;
-  bool paused_for_messages_;
   intptr_t live_ports_;  // The number of open ports, including control ports.
   intptr_t paused_;      // The number of pause messages received.
 #if !defined(PRODUCT)

runtime/vm/symbols.h

@@ -428,7 +428,6 @@ class ObjectPointerVisitor;
   V(ConstructorStacktracePrefix, "new ")                                       \
   V(_runExtension, "_runExtension")                                            \
   V(_runPendingImmediateCallback, "_runPendingImmediateCallback")              \
-  V(_ensureScheduleImmediate, "_ensureScheduleImmediate")                      \
   V(DartLibrary, "dart.library.")                                              \
   V(DartLibraryMirrors, "dart.library.mirrors")                                \
   V(_name, "_name")                                                            \

sdk/lib/io/annotations.dart

@@ -1,49 +0,0 @@
-// Copyright (c) 2017, 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.
-
-part of dart.io;
-
-/**
- * The annotation `@Experimental('message')` marks a feature as experimental.
- *
- * The annotation `@experimental` is shorthand that uses the default message
- * "This feature is experimental and not intended for general use".
- *
- * The intent of the `@Experimental` annotation is to inform users that a
- * feature has one ore more of the following issues:
- * - It is not yet stable,
- * - It may not work as documented,
- * - It should only be used by experts,
- * - It is not available in all environments.
- *
- * The documentation for an experimental feature should explain which of these
- * apply, and ideally give a reasonably safe example usage.
- *
- * A tool that processes Dart source code may give reports when experimental
- * features are used similarly to how they give reports for features marked
- * with the [Deprecated] annotation.
- */
-class Experimental {
-  /**
-   * A brief message describing how or why the feature is experimental.
-   */
-  final String message;
-
-  const Experimental({String message}) : this.message = message;
-
-  @override
-  String toString() {
-    if (message == null) {
-      return "This feature is experimental, and not intended for general use.";
-    } else {
-      return "This feature is experimental: $message";
-    }
-  }
-}
-
-/**
- * Marks a feature as experimental with the message, "Not intended for
- * general use".
- */
-const Experimental experimental = const Experimental();

sdk/lib/io/common.dart

@@ -117,67 +117,3 @@ _BufferAndStart _ensureFastAndSerializableByteData(
 class _IOCrypto {
   external static Uint8List getRandomBytes(int count);
 }
-
-// The implementation of waitForEventSync if there is one, and null otherwise.
-void Function(int timeoutMillis) _waitForEventSyncImpl;
-
-/**
- * Synchronously blocks the calling isolate to wait for asynchronous events to
- * complete.
- *
- * WARNING: EXPERIMENTAL. USE AT YOUR OWN RISK.
- *
- * If the [timeout] parameter is supplied, [waitForEventSync] will return after
- * the specified timeout even if no events have occurred.
- *
- * This call does the following:
- * - suspends the current execution stack,
- * - runs the microtask queue until it is empty,
- * - waits until the event queue is not empty,
- * - handles events on the event queue, plus their associated microtasks,
- *   until the event queue is empty,
- * - resumes the original stack.
- *
- * This function will synchronously throw the first exception it encounters in
- * running the microtasks and event handlers, leaving the remaining microtasks
- * and events on their respective queues.
- *
- * Please note that this call is only safe to make in code that is running in
- * the standalone command-line Dart VM. Further, because it suspends the current
- * execution stack until all other events have been processed, even when running
- * in the standalone command-line VM there exists a risk that the current
- * execution stack will be starved.
- *
- * Example:
- *
- * ```
- * main() {
- *   bool condition = false;
- *   ...
- *   // Some asynchronous opertion that eventually sets 'condition' true.
- *   ...
- *   print("Waiting for 'condition'");
- *   Duration timeout = const Duration(seconds: 10);
- *   Timer.run(() {});  // Ensure that there is at least one event.
- *   Stopwatch s = new Stopwatch()..start();
- *   while (!condition) {
- *     if (s.elapsed > timeout) {
- *       print("timed out waiting for 'condition'!");
- *       break;
- *     }
- *     print("still waiting...");
- *     waitForEventSync(timeout: timeout);
- *   }
- *   s.stop();
- * }
- * ```
- */
-@Experimental(message: "This feature is only available in the standalone VM")
-void waitForEventSync({Duration timeout}) {
-  if (_waitForEventSyncImpl == null) {
-    throw new UnsupportedError(
-        "waitForEventSync is not supported on this platform");
-  }
-  final int timeout_millis = timeout == null ? 0 : timeout.inMilliseconds;
-  _waitForEventSyncImpl(timeout_millis);
-}

sdk/lib/io/io.dart

@@ -205,7 +205,6 @@ import 'dart:typed_data';
 
 export 'dart:_http';
 
-part 'annotations.dart';
 part 'bytes_builder.dart';
 part 'common.dart';
 part 'data_transformer.dart';

sdk/lib/io/io_sources.gni

@@ -6,7 +6,6 @@ io_sdk_sources = [
   "io.dart",
 
   # The above file needs to be first if additional parts are added to the lib.
-  "annotations.dart",
   "bytes_builder.dart",
   "common.dart",
   "data_transformer.dart",

tests/standalone_2/io/wait_for_event_example_test.dart

@@ -1,39 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that example code in the doc comment for waitForEventSync is okay.
-
-main() {
-  asyncStart();
-  bool condition = false;
-
-  new Timer(const Duration(seconds: 2), () {
-    asyncEnd();
-    condition = true;
-  });
-
-  Duration timeout = const Duration(milliseconds: 100);
-  Timer.run(() {}); // Ensure that there is at least one event.
-  Stopwatch s = new Stopwatch()..start();
-  while (!condition) {
-    if (s.elapsed > timeout) {
-      break;
-    }
-    waitForEventSync(timeout: timeout);
-  }
-  s.stop();
-
-  Expect.isFalse(condition);
-  while (!condition) {
-    waitForEventSync();
-  }
-  Expect.isTrue(condition);
-}

tests/standalone_2/io/wait_for_event_exception_test.dart

@@ -1,22 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that exceptions thrown by message handlers running under
-// waitForEventSync() are propagated synchronously.
-
-main() {
-  asyncStart();
-  Timer.run(() {
-    asyncEnd();
-    throw "Exception";
-  });
-  Expect.throws(waitForEventSync, (e) => e is String);
-}

tests/standalone_2/io/wait_for_event_isolate_test.dart

@@ -1,41 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that waitForEventSync() returns on an Isolate message.
-
-messageSender(SendPort s) {
-  new Timer(const Duration(seconds: 1), () {
-    s.send(true);
-  });
-}
-
-main() {
-  asyncStart();
-  bool flag1 = false;
-  bool flag2 = false;
-  ReceivePort r = new ReceivePort();
-  Isolate.spawn(messageSender, r.sendPort).then((Isolate i) {
-    r.listen((message) {
-      flag1 = true;
-    });
-    Expect.isFalse(flag1);
-    waitForEventSync();
-    Expect.isTrue(flag1);
-    r.close();
-    flag2 = true;
-  });
-  Expect.isFalse(flag1);
-  Expect.isFalse(flag2);
-  waitForEventSync();
-  Expect.isTrue(flag1);
-  Expect.isTrue(flag2);
-  asyncEnd();
-}

tests/standalone_2/io/wait_for_event_microtask_test.dart

@@ -1,24 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that microtasks are run before waitForEventSync() blocks.
-
-main() {
-  asyncStart();
-  bool flag = false;
-  scheduleMicrotask(() {
-    flag = true;
-    asyncEnd();
-  });
-  Expect.isFalse(flag);
-  waitForEventSync(timeout: const Duration(milliseconds: 10));
-  Expect.isTrue(flag);
-}

tests/standalone_2/io/wait_for_event_nested_microtask_test.dart

@@ -1,34 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that waitForEventSync() drains microtasks before blocking even when
-// called from a microtask.
-
-main() {
-  asyncStart();
-  bool flag1 = false;
-  bool flag2 = false;
-  scheduleMicrotask(() {
-    scheduleMicrotask(() {
-      flag1 = true;
-      asyncEnd();
-    });
-    Expect.isFalse(flag1);
-    waitForEventSync(timeout: const Duration(milliseconds: 10));
-    Expect.isTrue(flag1);
-    flag2 = true;
-  });
-  Expect.isFalse(flag1);
-  Expect.isFalse(flag2);
-  waitForEventSync(timeout: const Duration(milliseconds: 10));
-  Expect.isTrue(flag1);
-  Expect.isTrue(flag2);
-}

tests/standalone_2/io/wait_for_event_nested_timer_microtask_test.dart

@@ -1,27 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that the microtasks for a message handler are run before
-// waitForEventSync() returns.
-
-main() {
-  asyncStart();
-  bool flag = false;
-  Timer.run(() {
-    scheduleMicrotask(() {
-      flag = true;
-      asyncEnd();
-    });
-  });
-  Expect.isFalse(flag);
-  waitForEventSync();
-  Expect.isTrue(flag);
-}

tests/standalone_2/io/wait_for_event_nested_timer_test.dart

@@ -1,30 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that all messages are processed before waitForEventSync() returns.
-
-main() {
-  asyncStart();
-  bool flag = false;
-  Timer.run(() {
-    Timer.run(() {
-      Timer.run(() {
-        Timer.run(() {
-          flag = true;
-          asyncEnd();
-        });
-      });
-    });
-  });
-  Expect.isFalse(flag);
-  waitForEventSync();
-  Expect.isTrue(flag);
-}

tests/standalone_2/io/wait_for_event_nested_waits_test.dart

@@ -1,69 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that waitForEventSync() works when called from a message handler.
-
-main() {
-  asyncStart();
-  bool flag1 = false;
-  bool flag2 = false;
-  bool flag3 = false;
-  bool flag4 = false;
-  Timer.run(() {
-    Timer.run(() {
-      Timer.run(() {
-        Timer.run(() {
-          flag1 = true;
-          asyncEnd();
-        });
-        Expect.isFalse(flag1);
-        Expect.isFalse(flag2);
-        Expect.isFalse(flag3);
-        Expect.isFalse(flag4);
-        waitForEventSync();
-        Expect.isTrue(flag1);
-        Expect.isFalse(flag2);
-        Expect.isFalse(flag3);
-        Expect.isFalse(flag4);
-        flag2 = true;
-      });
-      Expect.isFalse(flag1);
-      Expect.isFalse(flag2);
-      Expect.isFalse(flag3);
-      Expect.isFalse(flag4);
-      waitForEventSync();
-      Expect.isTrue(flag1);
-      Expect.isTrue(flag2);
-      Expect.isFalse(flag3);
-      Expect.isFalse(flag4);
-      flag3 = true;
-    });
-    Expect.isFalse(flag1);
-    Expect.isFalse(flag2);
-    Expect.isFalse(flag3);
-    Expect.isFalse(flag4);
-    waitForEventSync();
-    Expect.isTrue(flag1);
-    Expect.isTrue(flag2);
-    Expect.isTrue(flag3);
-    Expect.isFalse(flag4);
-    flag4 = true;
-  });
-  Expect.isFalse(flag1);
-  Expect.isFalse(flag2);
-  Expect.isFalse(flag3);
-  Expect.isFalse(flag4);
-  waitForEventSync();
-  Expect.isTrue(flag1);
-  Expect.isTrue(flag2);
-  Expect.isTrue(flag3);
-  Expect.isTrue(flag4);
-}

tests/standalone_2/io/wait_for_event_timeout_test.dart

@@ -1,22 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that waitForEventSync() respects its 'timeout' parameter.
-
-main() {
-  asyncStart();
-  Duration t = const Duration(seconds: 1);
-  Stopwatch s = new Stopwatch()..start();
-  waitForEventSync(timeout: t);
-  s.stop();
-  Expect.isTrue(s.elapsed > t);
-  asyncEnd();
-}

tests/standalone_2/io/wait_for_event_timer_test.dart

@@ -1,24 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that waitForEventSync() works in a simple case.
-
-main() {
-  asyncStart();
-  bool flag = false;
-  Timer.run(() {
-    flag = true;
-    asyncEnd();
-  });
-  Expect.isFalse(flag);
-  waitForEventSync();
-  Expect.isTrue(flag);
-}

tests/standalone_2/io/wait_for_event_zone_caught_error_test.dart

@@ -1,29 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that waitForEventSync() doesn't cause an error to escape a Zone that
-// has an error handler.
-
-main() {
-  asyncStart();
-  bool flag = false;
-  runZoned(() {
-    Timer.run(() {
-      asyncEnd();
-      throw "Exception";
-    });
-  }, onError: (e) {
-    flag = true;
-  });
-  Expect.isFalse(flag);
-  waitForEventSync();
-  Expect.isTrue(flag);
-}

tests/standalone_2/io/wait_for_event_zone_test.dart

@@ -1,27 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that waitForEventSync() works even when the message handler is run in
-// a different Zone.
-
-main() {
-  asyncStart();
-  bool flag = false;
-  runZoned(() {
-    Timer.run(() {
-      flag = true;
-      asyncEnd();
-    });
-  });
-  Expect.isFalse(flag);
-  waitForEventSync();
-  Expect.isTrue(flag);
-}

tests/standalone_2/io/wait_for_event_zone_uncaught_error_test.dart

@@ -1,24 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'dart:async';
-import 'dart:io';
-import 'dart:isolate';
-
-import 'package:async_helper/async_helper.dart';
-import 'package:expect/expect.dart';
-
-// Tests that an exception thrown from a message handler in a Zone without an
-// error handler is propagated synchronously.
-
-main() {
-  asyncStart();
-  runZoned(() {
-    Timer.run(() {
-      asyncEnd();
-      throw "Exception";
-    });
-  });
-  Expect.throws(waitForEventSync, (e) => e is String);
-}