New implementation of runZoned.

A combination of `runZoned` and `runZonedGuarded` where only the latter allows an `onError` parameter,
and only that has a nullable return type.

Retains the `onError` parameter on `runZoned` for now because it's too breaking to remove it until packages have been migrated off of it.
It will be removed in a follow-up CL.

Change-Id: If0e86c8d14e13fa089c66f4af975aeacb2616cf6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/137302
Reviewed-by: Jake Macdonald <jakemac@google.com>
Reviewed-by: Nate Bosch <nbosch@google.com>

CHANGELOG.md

@@ -13,6 +13,13 @@
   stack trace rather than propagate a `null` value.
   Error handling functions need no longer be prepared for `null` stack traces.
 
+* **Breaking change**: [#40681](https://github.com/dart-lang/sdk/issues/40681)
+  The `runZoned` function is split into two functions: `runZoned` and
+  `runZonedGuarded`, where the latter has a required `onError` parameter,
+  and the former has none.
+  This prepares the functions for Null Safety where the two functions will
+  differ in the nullability of their return types.
+
 #### `dart:core`
 
 * Adds `StackTrace.empty` constant which is the stack trace used as default
@@ -137,6 +144,18 @@ used (see Issue [39627][]).
     address in byte format for Internet addresses or raw file path for Unix
     domain addresses.
 
+* **Breaking change** [#40681](https://github.com/dart-lang/sdk/issues/40681)
+  The static method `runZoned` and `runWithHttpOverrides` on `HttpOverrides`
+  no longer accept `zoneSpecification` and `onError` parameters.
+  Use the `runZoned` or `runZonedGuarded` functions from `dart:async`
+  directly if needing to specify those.
+
+* **Breaking change** [#40681](https://github.com/dart-lang/sdk/issues/40681)
+  The static method `runZoned` and `runWithIOOverrides` on `IOOverrides`
+  no longer accept `zoneSpecification` and `onError` parameters.
+  Use the `runZoned` or `runZonedGuarded` functions from `dart:async`
+  directly if needing to specify those.
+
 #### `dart:mirrors`
 
 * Added `MirrorSystem.neverType`.

pkg/analysis_server/lib/src/analysis_server.dart

@@ -312,7 +312,7 @@ class AnalysisServer extends AbstractAnalysisServer {
   /// Handle a [request] that was read from the communication channel.
   void handleRequest(Request request) {
     performance.logRequestTiming(request.clientRequestTime);
-    runZoned(() {
+    runZonedGuarded(() {
       ServerPerformanceStatistics.serverRequests.makeCurrentWhile(() {
         int count = handlers.length;
         for (int i = 0; i < count; i++) {
@@ -341,7 +341,7 @@ class AnalysisServer extends AbstractAnalysisServer {
         }
         channel.sendResponse(Response.unknownRequest(request));
       });
-    }, onError: (exception, stackTrace) {
+    }, (exception, stackTrace) {
       AnalysisEngine.instance.instrumentationService.logException(
           FatalException('Failed to handle request: ${request.method}',
               exception, stackTrace));

pkg/analysis_server/lib/src/channel/byte_stream_channel.dart

@@ -144,9 +144,9 @@ class ByteStreamServerChannel implements ServerCommunicationChannel {
 
   /// Send the string [s] to [_output] followed by a newline.
   void _outputLine(String s) {
-    runZoned(() {
+    runZonedGuarded(() {
       _output.writeln(s);
-    }, onError: (e) {
+    }, (e, s) {
       close();
     });
   }

pkg/analysis_server/lib/src/domain_completion.dart

@@ -217,7 +217,7 @@ class CompletionDomainHandler extends AbstractRequestHandler {
       );
     }
 
-    return runZoned(() {
+    return runZonedGuarded(() {
       String requestName = request.method;
 
       if (requestName == COMPLETION_REQUEST_GET_SUGGESTION_DETAILS) {
@@ -233,7 +233,7 @@ class CompletionDomainHandler extends AbstractRequestHandler {
         return setSubscriptions(request);
       }
       return null;
-    }, onError: (exception, stackTrace) {
+    }, (exception, stackTrace) {
       AnalysisEngine.instance.instrumentationService.logException(
           CaughtException.withMessage(
               'Failed to handle completion domain request: ${request.method}',

pkg/analysis_server/lib/src/edit/edit_domain.dart

@@ -942,7 +942,7 @@ class _RefactoringManager {
           ?.sendEvent('refactor', params.kind.name.toLowerCase());
     }
 
-    runZoned(() async {
+    runZonedGuarded(() async {
       // TODO(brianwilkerson) Determine whether this await is necessary.
       await null;
       await _init(params.kind, file, params.offset, params.length);
@@ -990,7 +990,7 @@ class _RefactoringManager {
       _checkForReset_afterCreateChange();
       result.potentialEdits = nullIfEmpty(refactoring.potentialEditIds);
       _sendResultResponse();
-    }, onError: (exception, stackTrace) {
+    }, (exception, stackTrace) {
       if (exception is _ResetError ||
           exception is InconsistentAnalysisException) {
         cancel();

pkg/analysis_server/lib/src/lsp/channel/lsp_byte_stream_channel.dart

@@ -128,9 +128,9 @@ class LspByteStreamServerChannel implements LspServerCommunicationChannel {
 
   /// Send [bytes] to [_output].
   void _write(List<int> bytes) {
-    runZoned(
+    runZonedGuarded(
       () => _output.add(bytes),
-      onError: (e) => close(),
+      (e, s) => close(),
     );
   }
 }

pkg/analysis_server/lib/src/lsp/lsp_analysis_server.dart

@@ -245,7 +245,7 @@ class LspAnalysisServer extends AbstractAnalysisServer {
   /// Handle a [message] that was read from the communication channel.
   void handleMessage(Message message) {
     performance.logRequestTiming(null);
-    runZoned(() {
+    runZonedGuarded(() {
       ServerPerformanceStatistics.serverRequests.makeCurrentWhile(() async {
         try {
           if (message is ResponseMessage) {
@@ -284,7 +284,7 @@ class LspAnalysisServer extends AbstractAnalysisServer {
           logException(errorMessage, error, stackTrace);
         }
       });
-    }, onError: socketError);
+    }, socketError);
   }
 
   /// Logs the error on the client using window/logMessage.

runtime/tests/vm/dart/causal_stacks/utils.dart

@@ -140,10 +140,10 @@ Future listenAsyncStarThrowAsync() async {
 
 Future<void> customErrorZone() async {
   final completer = Completer<void>();
-  runZoned(() async {
+  runZonedGuarded(() async {
     await allYield();
     completer.complete(null);
-  }, onError: (e, s) {
+  }, (e, s) {
     completer.completeError(e, s);
   });
   return completer.future;
@@ -550,7 +550,7 @@ Future<void> doTestsCausal() async {
     r'#5      _rootRun ',
     r'#6      _CustomZone.run ',
     r'#7      _runZoned ',
-    r'#8      runZoned ',
+    r'#8      runZonedGuarded ',
     r'#9      customErrorZone \(.*/utils.dart:143(:3)?\)$',
   ];
   await doTestAwait(

runtime/tests/vm/dart/isolate_send_function_types_test.dart

@@ -14,9 +14,9 @@ main(args) async {
 
   {
     final caughtErrorCompleter = Completer<String>();
-    await runZoned(() {
+    await runZonedGuarded(() {
       Isolate.spawn(isolate, x);
-    }, onError: (e) {
+    }, (e, s) {
       caughtErrorCompleter.complete(e.toString());
     });
     Expect.equals(

sdk/lib/_http/overrides.dart

@@ -51,27 +51,20 @@ abstract class HttpOverrides {
   static R runZoned<R>(R body(),
       {HttpClient Function(SecurityContext) createHttpClient,
       String Function(Uri uri, Map<String, String> environment)
-          findProxyFromEnvironment,
-      ZoneSpecification zoneSpecification,
-      Function onError}) {
+          findProxyFromEnvironment}) {
     HttpOverrides overrides =
         new _HttpOverridesScope(createHttpClient, findProxyFromEnvironment);
     return _asyncRunZoned<R>(body,
-        zoneValues: {_httpOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+        zoneValues: {_httpOverridesToken: overrides});
   }
 
   /// Runs [body] in a fresh [Zone] using the overrides found in [overrides].
   ///
   /// Note that [overrides] should be an instance of a class that extends
   /// [HttpOverrides].
-  static R runWithHttpOverrides<R>(R body(), HttpOverrides overrides,
-      {ZoneSpecification zoneSpecification, Function onError}) {
+  static R runWithHttpOverrides<R>(R body(), HttpOverrides overrides) {
     return _asyncRunZoned<R>(body,
-        zoneValues: {_httpOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+        zoneValues: {_httpOverridesToken: overrides});
   }
 
   /// Returns a new [HttpClient] using the given [context].

sdk/lib/async/zone.dart

@@ -1467,43 +1467,91 @@ const _rootZone = const _RootZone();
  *       var future2 = future.then((_) { throw "error in first error-zone"; });
  *       runZoned(() {
  *         var future3 = future2.catchError((e) { print("Never reached!"); });
- *       }, onError: (e) { print("unused error handler"); });
- *     }, onError: (e) { print("catches error of first error-zone."); });
+ *       }, onError: (e, s) { print("unused error handler"); });
+ *     }, onError: (e, s) { print("catches error of first error-zone."); });
  *
  * Example:
  *
  *     runZoned(() {
  *       new Future(() { throw "asynchronous error"; });
- *     }, onError: print);  // Will print "asynchronous error".
+ *     }, onError: (e, s) => print(e));  // Will print "asynchronous error".
  *
  * It is possible to manually pass an error from one error zone to another
  * by re-throwing it in the new zone. If [onError] throws, that error will
  * occur in the original zone where [runZoned] was called.
  */
 R runZoned<R>(R body(),
-    {Map zoneValues, ZoneSpecification zoneSpecification, Function onError}) {
-  if (onError == null) {
+    {Map zoneValues,
+    ZoneSpecification zoneSpecification,
+    @Deprecated("Use runZonedGuarded instead") Function onError}) {
+  ArgumentError.checkNotNull(body, "body");
+
+  if (onError != null) {
+    void Function(Object, StackTrace) typedOnError;
+    if (onError is void Function(Object, StackTrace)) {
+      typedOnError = onError;
+    } else if (onError is void Function(Object)) {
+      typedOnError = (Object e, StackTrace _) => onError(e);
+    } else {
+      throw ArgumentError.value(onError, "onError",
+          "Should accept one error, or one error and a stack trace");
+    }
+    return runZonedGuarded(body, typedOnError,
+        zoneValues: zoneValues, zoneSpecification: zoneSpecification);
+  }
   return _runZoned<R>(body, zoneValues, zoneSpecification);
 }
-  void Function(Object) unaryOnError;
-  void Function(Object, StackTrace) binaryOnError;
-  if (onError is void Function(Object, StackTrace)) {
-    binaryOnError = onError;
-  } else if (onError is void Function(Object)) {
-    unaryOnError = onError;
-  } else {
-    throw new ArgumentError("onError callback must take either an Object "
-        "(the error), or both an Object (the error) and a StackTrace.");
-  }
+
+/**
+ * Runs [body] in its own error zone.
+ *
+ * Creates a new zone using [Zone.fork] based on [zoneSpecification] and
+ * [zoneValues], then runs [body] in that zone and returns the result.
+ *
+ * The [onError] function is used *both* to handle asynchronous errors
+ * by overriding [ZoneSpecification.handleUncaughtError] in [zoneSpecification],
+ * if any, *and* to handle errors thrown synchronously by the call to [body].
+ *
+ * If an error occurs synchronously in [body],
+ * then throwing in the [onError] handler
+ * makes the call to `runZonedGuarded` throw that error,
+ * and otherwise the call to `runZonedGuarded` returns `null`.
+ *
+ * If the zone specification has a `handleUncaughtError` value or the [onError]
+ * parameter is provided, the zone becomes an error-zone.
+ *
+ * Errors will never cross error-zone boundaries by themselves.
+ * Errors that try to cross error-zone boundaries are considered uncaught in
+ * their originating error zone.
+ *
+ *     var future = new Future.value(499);
+ *     runZoned(() {
+ *       var future2 = future.then((_) { throw "error in first error-zone"; });
+ *       runZoned(() {
+ *         var future3 = future2.catchError((e) { print("Never reached!"); });
+ *       }, onError: (e, s) { print("unused error handler"); });
+ *     }, onError: (e, s) { print("catches error of first error-zone."); });
+ *
+ * Example:
+ *
+ *     runZoned(() {
+ *       new Future(() { throw "asynchronous error"; });
+ *     }, onError: (e, s) => print(e));  // Will print "asynchronous error".
+ *
+ * It is possible to manually pass an error from one error zone to another
+ * by re-throwing it in the new zone. If [onError] throws, that error will
+ * occur in the original zone where [runZoned] was called.
+ */
+@Since("2.8")
+R runZonedGuarded<R>(R body(), void onError(Object error, StackTrace stack),
+    {Map zoneValues, ZoneSpecification zoneSpecification}) {
+  ArgumentError.checkNotNull(body, "body");
+  ArgumentError.checkNotNull(onError, "onError");
+
   HandleUncaughtErrorHandler errorHandler = (Zone self, ZoneDelegate parent,
       Zone zone, error, StackTrace stackTrace) {
     try {
-      if (binaryOnError != null) {
-        self.parent.runBinary(binaryOnError, error, stackTrace);
-      } else {
-        assert(unaryOnError != null);
-        self.parent.runUnary(unaryOnError, error);
-      }
+      self.parent.runBinary(onError, error, stackTrace);
     } catch (e, s) {
       if (identical(e, error)) {
         parent.handleUncaughtError(zone, error, stackTrace);
@@ -1521,13 +1569,8 @@ R runZoned<R>(R body(),
   }
   try {
     return _runZoned<R>(body, zoneValues, zoneSpecification);
-  } catch (e, stackTrace) {
-    if (binaryOnError != null) {
-      binaryOnError(e, stackTrace);
-    } else {
-      assert(unaryOnError != null);
-      unaryOnError(e);
-    }
+  } catch (error, stackTrace) {
+    onError(error, stackTrace);
   }
   return null;
 }

sdk/lib/io/overrides.dart

@@ -92,11 +92,7 @@ abstract class IOOverrides {
       // ServerSocket
       Future<ServerSocket> Function(dynamic, int,
               {int backlog, bool v6Only, bool shared})
-          serverSocketBind,
-
-      // Optional Zone parameters
-      ZoneSpecification zoneSpecification,
-      Function onError}) {
+          serverSocketBind}) {
     IOOverrides overrides = new _IOOverridesScope(
       // Directory
       createDirectory,
@@ -131,22 +127,15 @@ abstract class IOOverrides {
       // ServerSocket
       serverSocketBind,
     );
-    return _asyncRunZoned<R>(body,
-        zoneValues: {_ioOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+    return _asyncRunZoned<R>(body, zoneValues: {_ioOverridesToken: overrides});
   }
 
   /// Runs [body] in a fresh [Zone] using the overrides found in [overrides].
   ///
   /// Note that [overrides] should be an instance of a class that extends
   /// [IOOverrides].
-  static R runWithIOOverrides<R>(R body(), IOOverrides overrides,
-      {ZoneSpecification zoneSpecification, Function onError}) {
-    return _asyncRunZoned<R>(body,
-        zoneValues: {_ioOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+  static R runWithIOOverrides<R>(R body(), IOOverrides overrides) {
+    return _asyncRunZoned<R>(body, zoneValues: {_ioOverridesToken: overrides});
   }
 
   // Directory

sdk_nnbd/lib/_http/overrides.dart

@@ -49,27 +49,20 @@ abstract class HttpOverrides {
   static R runZoned<R>(R body(),
       {HttpClient Function(SecurityContext?)? createHttpClient,
       String Function(Uri uri, Map<String, String>? environment)?
-          findProxyFromEnvironment,
-      ZoneSpecification? zoneSpecification,
-      Function? onError}) {
+          findProxyFromEnvironment}) {
     HttpOverrides overrides =
         new _HttpOverridesScope(createHttpClient, findProxyFromEnvironment);
     return _asyncRunZoned<R>(body,
-        zoneValues: {_httpOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+        zoneValues: {_httpOverridesToken: overrides});
   }
 
   /// Runs [body] in a fresh [Zone] using the overrides found in [overrides].
   ///
   /// Note that [overrides] should be an instance of a class that extends
   /// [HttpOverrides].
-  static R runWithHttpOverrides<R>(R body(), HttpOverrides overrides,
-      {ZoneSpecification? zoneSpecification, Function? onError}) {
+  static R runWithHttpOverrides<R>(R body(), HttpOverrides overrides) {
     return _asyncRunZoned<R>(body,
-        zoneValues: {_httpOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+        zoneValues: {_httpOverridesToken: overrides});
   }
 
   /// Returns a new [HttpClient] using the given [context].

sdk_nnbd/lib/async/zone.dart

@@ -1465,7 +1465,7 @@ const _Zone _rootZone = const _RootZone();
  * If an error occurs synchronously in [body],
  * then throwing in the [onError] handler
  * makes the call to `runZone` throw that error,
- * and otherwise the call to `runZoned` returns `null`.
+ * and otherwise the call to `runZoned` attempt to return `null`.
  *
  * If the zone specification has a `handleUncaughtError` value or the [onError]
  * parameter is provided, the zone becomes an error-zone.
@@ -1474,19 +1474,19 @@ const _Zone _rootZone = const _RootZone();
  * Errors that try to cross error-zone boundaries are considered uncaught in
  * their originating error zone.
  *
- *     var future = Future.value(499);
+ *     var future = new Future.value(499);
  *     runZoned(() {
  *       var future2 = future.then((_) { throw "error in first error-zone"; });
  *       runZoned(() {
  *         var future3 = future2.catchError((e) { print("Never reached!"); });
- *       }, onError: (e) { print("unused error handler"); });
- *     }, onError: (e) { print("catches error of first error-zone."); });
+ *       }, onError: (e, s) { print("unused error handler"); });
+ *     }, onError: (e, s) { print("catches error of first error-zone."); });
  *
  * Example:
  *
  *     runZoned(() {
  *       new Future(() { throw "asynchronous error"; });
- *     }, onError: print);  // Will print "asynchronous error".
+ *     }, onError: (e, s) => print(e));  // Will print "asynchronous error".
  *
  * It is possible to manually pass an error from one error zone to another
  * by re-throwing it in the new zone. If [onError] throws, that error will
@@ -1495,30 +1495,74 @@ const _Zone _rootZone = const _RootZone();
 R runZoned<R>(R body(),
     {Map<Object?, Object?>? zoneValues,
     ZoneSpecification? zoneSpecification,
-    Function? onError}) {
-  if (onError == null) {
+    @Deprecated("Use runZonedGuarded instead") Function? onError}) {
+  ArgumentError.checkNotNull(body, "body");
+  if (onError != null) {
+    // TODO: Remove this when code have been migrated off using [onError].
+    if (onError is! void Function(Object, StackTrace)) {
+      if (onError is void Function(Object)) {
+        var originalOnError = onError;
+        onError = (Object error, StackTrace stack) => originalOnError(error);
+      } else {
+        throw ArgumentError.value(onError, "onError",
+            "Must be Function(Object) or Function(Object, StackTrace)");
+      }
+    }
+    return runZonedGuarded(body, onError,
+        zoneSpecification: zoneSpecification, zoneValues: zoneValues) as R;
+  }
   return _runZoned<R>(body, zoneValues, zoneSpecification);
 }
-  void Function(Object)? unaryOnError;
-  void Function(Object, StackTrace)? binaryOnError;
-  if (onError is void Function(Object, StackTrace)) {
-    binaryOnError = onError;
-  } else if (onError is void Function(Object)) {
-    unaryOnError = onError;
-  } else {
-    throw new ArgumentError("onError callback must take either an Object "
-        "(the error), or both an Object (the error) and a StackTrace.");
-  }
+
+/**
+ * Runs [body] in its own error zone.
+ *
+ * Creates a new zone using [Zone.fork] based on [zoneSpecification] and
+ * [zoneValues], then runs [body] in that zone and returns the result.
+ *
+ * The [onError] function is used *both* to handle asynchronous errors
+ * by overriding [ZoneSpecification.handleUncaughtError] in [zoneSpecification],
+ * if any, *and* to handle errors thrown synchronously by the call to [body].
+ *
+ * If an error occurs synchronously in [body],
+ * then throwing in the [onError] handler
+ * makes the call to `runZonedGuarded` throw that error,
+ * and otherwise the call to `runZonedGuarded` returns `null`.
+ *
+ * The zone will always be an error-zone.
+ *
+ * Errors will never cross error-zone boundaries by themselves.
+ * Errors that try to cross error-zone boundaries are considered uncaught in
+ * their originating error zone.
+ * ```dart
+ * var future = Future.value(499);
+ * runZonedGuarded(() {
+ *   var future2 = future.then((_) { throw "error in first error-zone"; });
+ *   runZonedGuarded(() {
+ *     var future3 = future2.catchError((e) { print("Never reached!"); });
+ *   }, (e, s) { print("unused error handler"); });
+ * }, (e, s) { print("catches error of first error-zone."); });
+ * ```
+ * Example:
+ * ```dart
+ * runZonedGuarded(() {
+ *   new Future(() { throw "asynchronous error"; });
+ * }, (e, s) => print(e));  // Will print "asynchronous error".
+ * ```
+ * It is possible to manually pass an error from one error zone to another
+ * by re-throwing it in the new zone. If [onError] throws, that error will
+ * occur in the original zone where [runZoned] was called.
+ */
+@Since("2.8")
+R? runZonedGuarded<R>(R body(), void onError(Object error, StackTrace stack),
+    {Map<Object?, Object?>? zoneValues, ZoneSpecification? zoneSpecification}) {
+  ArgumentError.checkNotNull(body, "body");
+  ArgumentError.checkNotNull(onError, "onError");
   _Zone parentZone = Zone._current;
   HandleUncaughtErrorHandler errorHandler = (Zone self, ZoneDelegate parent,
       Zone zone, Object error, StackTrace stackTrace) {
     try {
-      if (binaryOnError != null) {
-        parentZone.runBinary(binaryOnError, error, stackTrace);
-      } else {
-        assert(unaryOnError != null);
-        parentZone.runUnary(unaryOnError!, error);
-      }
+      parentZone.runBinary(onError, error, stackTrace);
     } catch (e, s) {
       if (identical(e, error)) {
         parent.handleUncaughtError(zone, error, stackTrace);
@@ -1536,17 +1580,10 @@ R runZoned<R>(R body(),
   }
   try {
     return _runZoned<R>(body, zoneValues, zoneSpecification);
-  } catch (e, stackTrace) {
-    if (binaryOnError != null) {
-      binaryOnError(e, stackTrace);
-    } else {
-      assert(unaryOnError != null);
-      unaryOnError!(e);
+  } catch (error, stackTrace) {
+    onError(error, stackTrace);
   }
-  }
-  // TODO(lrn): Change behavior to throw the actual resulting error,
-  // perhaps even synchronously.
-  return null as R;
+  return null;
 }
 
 /// Runs [body] in a new zone based on [zoneValues] and [specification].

sdk_nnbd/lib/io/overrides.dart

@@ -90,11 +90,7 @@ abstract class IOOverrides {
       // ServerSocket
       Future<ServerSocket> Function(dynamic, int,
               {int backlog, bool v6Only, bool shared})?
-          serverSocketBind,
-
-      // Optional Zone parameters
-      ZoneSpecification? zoneSpecification,
-      Function? onError}) {
+          serverSocketBind}) {
     IOOverrides overrides = new _IOOverridesScope(
       // Directory
       createDirectory,
@@ -129,22 +125,15 @@ abstract class IOOverrides {
       // ServerSocket
       serverSocketBind,
     );
-    return _asyncRunZoned<R>(body,
-        zoneValues: {_ioOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+    return _asyncRunZoned<R>(body, zoneValues: {_ioOverridesToken: overrides});
   }
 
   /// Runs [body] in a fresh [Zone] using the overrides found in [overrides].
   ///
   /// Note that [overrides] should be an instance of a class that extends
   /// [IOOverrides].
-  static R runWithIOOverrides<R>(R body(), IOOverrides overrides,
-      {ZoneSpecification? zoneSpecification, Function? onError}) {
-    return _asyncRunZoned<R>(body,
-        zoneValues: {_ioOverridesToken: overrides},
-        zoneSpecification: zoneSpecification,
-        onError: onError);
+  static R runWithIOOverrides<R>(R body(), IOOverrides overrides) {
+    return _asyncRunZoned<R>(body, zoneValues: {_ioOverridesToken: overrides});
   }
 
   // Directory

tests/lib/async/catch_errors.dart

@@ -11,7 +11,7 @@ Stream catchErrors(dynamic body()) {
   }
 
   void onListen() {
-    runZoned(body, onError: onError);
+    runZonedGuarded(body, onError);
   }
 
   controller = new StreamController(onListen: onListen);
@@ -21,7 +21,7 @@ Stream catchErrors(dynamic body()) {
 runZonedScheduleMicrotask(body(),
     {void onScheduleMicrotask(void callback()), Function? onError}) {
   if (onScheduleMicrotask == null) {
-    return runZoned(body, onError: onError);
+    return runZonedGuarded(body, onError);
   }
   HandleUncaughtErrorHandler errorHandler;
   if (onError != null) {

tests/lib/async/future_test.dart

@@ -868,7 +868,7 @@ void testWaitCleanUpError() {
   asyncStart();
   asyncStart();
   asyncStart();
-  runZoned(() {
+  runZonedGuarded(() {
     Future.wait([
       new Future.delayed(cms, () => 0),
       new Future.delayed(cms * 2, () => throw 1),
@@ -882,7 +882,7 @@ void testWaitCleanUpError() {
       Expect.equals(e, 1);
       asyncEnd();
     });
-  }, onError: (e, s) {
+  }, (e, s) {
     int index = e;
     Expect.isTrue(index == 0 || index == 2, "$index");
     Expect.isFalse(uncaughts[index]);

tests/lib/async/run_zoned4_test.dart

@@ -10,7 +10,7 @@ main() {
   // error handler is defined.
   Expect.equals(
       499,
-      runZoned(() => 499, onError: (e) {
+      runZonedGuarded(() => 499, (e, s) {
         throw "Unexpected";
       }));
 }

tests/lib/async/run_zoned5_test.dart

@@ -9,9 +9,9 @@ import 'dart:async';
 main() {
   asyncStart();
   // Ensure that `runZoned`'s onError handles synchronous errors.
-  runZoned(() {
+  runZonedGuarded(() {
     throw 0;
-  }, onError: (e) {
+  }, (e, s) {
     Expect.equals(0, e);
     asyncEnd();
   });

tests/lib/async/run_zoned6_test.dart

@@ -12,9 +12,9 @@ main() {
   // in the error handler at that point (when it is a synchronous error) yields
   // a synchronous error.
   try {
-    runZoned(() {
+    runZonedGuarded(() {
       throw 0;
-    }, onError: (e) {
+    }, (e, s) {
       Expect.equals(0, e);
       throw e;  //#01 : ok
       asyncEnd();

tests/lib/async/run_zoned8_test.dart

@@ -13,7 +13,7 @@ main() {
 
   var events = [];
   // Test runZoned with periodic Timers.
-  runZoned(() {
+  runZonedGuarded(() {
     int counter = 0;
     new Timer.periodic(const Duration(milliseconds: 50), (timer) {
       if (counter == 1) {
@@ -24,7 +24,7 @@ main() {
       events.add(counter);
       throw counter;
     });
-  }, onError: (e, [s]) {
+  }, (e, [s]) {
     events.add("error: $e");
     Expect.isNotNull(s); // Regression test for http://dartbug.com/33589
   });

tests/lib/async/run_zoned9_test.dart

@@ -12,15 +12,15 @@ main() {
   // to the next runZoned when the handler returns false.
   bool sawInnerHandler = false;
   try {
-    runZoned(() {
+    runZonedGuarded(() {
       runZoned(() {
         throw 0;
-      }, onError: (e) {
+      }, onError: (e, s) {
         Expect.equals(0, e);
         sawInnerHandler = true;
         throw e;
       });
-    }, onError: (e) {
+    }, (e, s) {
       Expect.equals(0, e);
       Expect.isTrue(sawInnerHandler);
       // If we are waiting for an error, don't asyncEnd, but let it time out.

tests/lib/async/stream_event_transformed_test.dart

@@ -267,7 +267,7 @@ main() {
 
     bool streamIsDone = false;
     int errorCount = 0;
-    runZoned(() {
+    runZonedGuarded(() {
       controller.stream
           .transform(new SinkTransformer((sink) =>
               new FutureWaitingTransformerSink(sink, closeCompleter.future)))
@@ -280,7 +280,7 @@ main() {
         Expect.listEquals([], events);
         streamIsDone = true;
       });
-    }, onError: (e) {
+    }, (e, s) {
       Expect.isTrue(e is StateError);
       errorCount++;
     });

tests/lib/async/stream_subscription_as_future_test.dart

@@ -114,7 +114,7 @@ main() {
   });
 
   test("subscription.asFuture failure in cancel", () {
-    runZoned(() {
+    runZonedGuarded(() {
       var completer = new Completer();
       var controller =
           new StreamController(onCancel: () => completer.future, sync: true);
@@ -135,7 +135,7 @@ main() {
         Expect.isFalse(catchErrorHasRun);
         completer.completeError(499);
       }));
-    }, onError: expectAsync((e) {
+    }, expectAsync2((e, s) {
       Expect.equals(499, e);
     }));
   });

tests/lib/async/stream_zones_test.dart

@@ -10,8 +10,8 @@ import 'dart:async';
 test1() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
-    runZoned(() {
+  runZonedGuarded(() {
+    runZonedGuarded(() {
       var c = new StreamController();
       c.stream.listen((x) => events.add("stream: $x"),
           onError: (x) => events.add("stream: error $x"),
@@ -19,8 +19,8 @@ test1() {
       c.add(1);
       c.addError(2);
       c.close();
-    }, onError: (x) => events.add("rza: error $x"));
-  }, onError: (x) => events.add("rzb: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -33,18 +33,18 @@ test1() {
 test2() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c;
-    runZoned(() {
+    runZonedGuarded(() {
       c = new StreamController();
       c.stream.listen((x) => events.add("stream: $x"),
           onError: (x) => events.add("stream: error $x"),
           onDone: done.complete);
-    }, onError: (x) => events.add("rza: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
     c.add(1);
     c.addError(2);
     c.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -57,16 +57,16 @@ test2() {
 test3() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-    runZoned(() {
+    runZonedGuarded(() {
       c.add(1);
       c.addError(2);
       c.close();
-    }, onError: (x) => events.add("rza: error $x"));
-  }, onError: (x) => events.add("rzb: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -79,18 +79,18 @@ test3() {
 test4() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-    runZoned(() {
+    runZonedGuarded(() {
       var c2 = new StreamController();
       c.addStream(c2.stream).whenComplete(c.close);
       c2.add(1);
       c2.addError(2);
       c2.close();
-    }, onError: (x) => events.add("rza: error $x"));
-  }, onError: (x) => events.add("rzb: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -104,20 +104,20 @@ test4() {
 test5() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c;
-    runZoned(() {
+    runZonedGuarded(() {
       c = new StreamController();
       c.stream.listen((x) => events.add("stream: $x"),
           onError: (x) => events.add("stream: error $x"),
           onDone: done.complete);
-    }, onError: (x) => events.add("rza: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
     var c2 = new StreamController();
     c.addStream(c2.stream).whenComplete(c.close);
     c2.add(1);
     c2.addError(2);
     c2.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -130,18 +130,18 @@ test6() {
   var events = [];
   var done = new Completer();
   var c;
-  runZoned(() {
+  runZonedGuarded(() {
     c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-  }, onError: (x) => events.add("rza: error $x"));
-  runZoned(() {
+  }, (e, s) => events.add("rza: error $e"));
+  runZonedGuarded(() {
     var c2 = new StreamController();
     c.addStream(c2.stream).whenComplete(c.close);
     c2.add(1);
     c2.addError(2);
     c2.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e, s"));
   return [
     done.future,
     () {
@@ -155,16 +155,16 @@ test7() {
   var events = [];
   var done = new Completer();
   var c;
-  runZoned(() {
+  runZonedGuarded(() {
     c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-  }, onError: (x) => events.add("rza: error $x"));
-  runZoned(() {
+  }, (e, s) => events.add("rza: error $e"));
+  runZonedGuarded(() {
     c.add(1);
     c.addError(2);
     c.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {

tests/lib_2/async/run_zoned4_test.dart

@@ -10,7 +10,7 @@ main() {
   // error handler is defined.
   Expect.equals(
       499,
-      runZoned(() => 499, onError: (e) {
+      runZonedGuarded(() => 499, (e, s) {
         throw "Unexpected";
       }));
 }

tests/lib_2/async/run_zoned5_test.dart

@@ -9,9 +9,9 @@ import 'dart:async';
 main() {
   asyncStart();
   // Ensure that `runZoned`'s onError handles synchronous errors.
-  runZoned(() {
+  runZonedGuarded(() {
     throw 0;
-  }, onError: (e) {
+  }, (e, s) {
     Expect.equals(0, e);
     asyncEnd();
   });

tests/lib_2/async/run_zoned6_test.dart

@@ -12,9 +12,9 @@ main() {
   // in the error handler at that point (when it is a synchronous error) yields
   // a synchronous error.
   try {
-    runZoned(() {
+    runZonedGuarded(() {
       throw 0;
-    }, onError: (e) {
+    }, (e, s) {
       Expect.equals(0, e);
       throw e;  //#01 : ok
       asyncEnd();

tests/lib_2/async/run_zoned9_test.dart

@@ -12,15 +12,15 @@ main() {
   // to the next runZoned when the handler returns false.
   bool sawInnerHandler = false;
   try {
-    runZoned(() {
-      runZoned(() {
+    runZonedGuarded(() {
+      runZonedGuarded(() {
         throw 0;
-      }, onError: (e) {
+      }, (e, s) {
         Expect.equals(0, e);
         sawInnerHandler = true;
         throw e;
       });
-    }, onError: (e) {
+    }, (e, s) {
       Expect.equals(0, e);
       Expect.isTrue(sawInnerHandler);
       // If we are waiting for an error, don't asyncEnd, but let it time out.

tests/lib_2/async/stream_event_transformed_test.dart

@@ -267,7 +267,7 @@ main() {
 
     bool streamIsDone = false;
     int errorCount = 0;
-    runZoned(() {
+    runZonedGuarded(() {
       controller.stream
           .transform(new SinkTransformer((sink) =>
               new FutureWaitingTransformerSink(sink, closeCompleter.future)))
@@ -280,7 +280,7 @@ main() {
         Expect.listEquals([], events);
         streamIsDone = true;
       });
-    }, onError: (e) {
+    }, (e, s) {
       Expect.isTrue(e is StateError);
       errorCount++;
     });

tests/lib_2/async/stream_subscription_as_future_test.dart

@@ -114,7 +114,7 @@ main() {
   });
 
   test("subscription.asFuture failure in cancel", () {
-    runZoned(() {
+    runZonedGuarded(() {
       var completer = new Completer();
       var controller =
           new StreamController(onCancel: () => completer.future, sync: true);
@@ -135,7 +135,7 @@ main() {
         Expect.isFalse(catchErrorHasRun);
         completer.completeError(499);
       }));
-    }, onError: expectAsync((e) {
+    }, expectAsync2((e, s) {
       Expect.equals(499, e);
     }));
   });

tests/lib_2/async/stream_zones_test.dart

@@ -10,8 +10,8 @@ import 'dart:async';
 test1() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
-    runZoned(() {
+  runZonedGuarded(() {
+    runZonedGuarded(() {
       var c = new StreamController();
       c.stream.listen((x) => events.add("stream: $x"),
           onError: (x) => events.add("stream: error $x"),
@@ -19,8 +19,8 @@ test1() {
       c.add(1);
       c.addError(2);
       c.close();
-    }, onError: (x) => events.add("rza: error $x"));
-  }, onError: (x) => events.add("rzb: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -33,18 +33,18 @@ test1() {
 test2() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c;
-    runZoned(() {
+    runZonedGuarded(() {
       c = new StreamController();
       c.stream.listen((x) => events.add("stream: $x"),
           onError: (x) => events.add("stream: error $x"),
           onDone: done.complete);
-    }, onError: (x) => events.add("rza: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
     c.add(1);
     c.addError(2);
     c.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -57,16 +57,16 @@ test2() {
 test3() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-    runZoned(() {
+    runZonedGuarded(() {
       c.add(1);
       c.addError(2);
       c.close();
-    }, onError: (x) => events.add("rza: error $x"));
-  }, onError: (x) => events.add("rzb: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -79,18 +79,18 @@ test3() {
 test4() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-    runZoned(() {
+    runZonedGuarded(() {
       var c2 = new StreamController();
       c.addStream(c2.stream).whenComplete(c.close);
       c2.add(1);
       c2.addError(2);
       c2.close();
-    }, onError: (x) => events.add("rza: error $x"));
-  }, onError: (x) => events.add("rzb: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -104,20 +104,20 @@ test4() {
 test5() {
   var events = [];
   var done = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     var c;
-    runZoned(() {
+    runZonedGuarded(() {
       c = new StreamController();
       c.stream.listen((x) => events.add("stream: $x"),
           onError: (x) => events.add("stream: error $x"),
           onDone: done.complete);
-    }, onError: (x) => events.add("rza: error $x"));
+    }, (e, s) => events.add("rza: error $e"));
     var c2 = new StreamController();
     c.addStream(c2.stream).whenComplete(c.close);
     c2.add(1);
     c2.addError(2);
     c2.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -130,18 +130,18 @@ test6() {
   var events = [];
   var done = new Completer();
   var c;
-  runZoned(() {
+  runZonedGuarded(() {
     c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-  }, onError: (x) => events.add("rza: error $x"));
-  runZoned(() {
+  }, (e, s) => events.add("rza: error $e"));
+  runZonedGuarded(() {
     var c2 = new StreamController();
     c.addStream(c2.stream).whenComplete(c.close);
     c2.add(1);
     c2.addError(2);
     c2.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {
@@ -155,16 +155,16 @@ test7() {
   var events = [];
   var done = new Completer();
   var c;
-  runZoned(() {
+  runZonedGuarded(() {
     c = new StreamController();
     c.stream.listen((x) => events.add("stream: $x"),
         onError: (x) => events.add("stream: error $x"), onDone: done.complete);
-  }, onError: (x) => events.add("rza: error $x"));
-  runZoned(() {
+  }, (e, s) => events.add("rza: error $e"));
+  runZonedGuarded(() {
     c.add(1);
     c.addError(2);
     c.close();
-  }, onError: (x) => events.add("rzb: error $x"));
+  }, (e, s) => events.add("rzb: error $e"));
   return [
     done.future,
     () {

tests/standalone/io/async_catch_errors_test.dart

@@ -12,11 +12,11 @@ var events = [];
 
 Future testSocketException() {
   var completer = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     Socket.connect("4", 1).then((Socket s) {
       Expect.fail("Socket should not be able to connect");
     });
-  }, onError: (err) {
+  }, (err, s) {
     if (err is! SocketException) Expect.fail("Not expected error: $err");
     completer.complete("socket test, ok.");
     events.add("SocketException");
@@ -26,9 +26,9 @@ Future testSocketException() {
 
 Future testFileSystemException() {
   var completer = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     new File("lol it's not a file\n").openRead().listen(null);
-  }, onError: (err) {
+  }, (err, s) {
     if (err is! FileSystemException) Expect.fail("Not expected error: $err");
     completer.complete("file test, ok.");
     events.add("FileSystemException");

tests/standalone/io/file_system_watcher_test.dart

@@ -452,11 +452,11 @@ testWatchOverflow() async {
 }
 
 void watcher(SendPort sendPort) async {
-  runZoned(() {
+  runZonedGuarded(() {
     var watcher = Directory.systemTemp.watch(recursive: true);
     watcher.listen((data) async {});
     sendPort.send('start');
-  }, onError: (error) {
+  }, (error, stack) {
     print(error);
     sendPort.send('end');
   });

tests/standalone/io/http_server_test.dart

@@ -159,7 +159,7 @@ void testHttpServerZone() {
 void testHttpServerZoneError() {
   asyncStart();
   Expect.equals(Zone.root, Zone.current);
-  runZoned(() {
+  runZonedGuarded(() {
     Expect.notEquals(Zone.root, Zone.current);
     HttpServer.bind("127.0.0.1", 0).then((server) {
       Expect.notEquals(Zone.root, Zone.current);
@@ -178,14 +178,14 @@ void testHttpServerZoneError() {
         socket.listen(null);
       });
     });
-  }, onError: (e) {
+  }, (e, s) {
     asyncEnd();
   });
 }
 
 void testHttpServerClientClose() {
   HttpServer.bind("127.0.0.1", 0).then((server) {
-    runZoned(() {
+    runZonedGuarded(() {
       server.listen((request) {
         request.response.bufferOutput = false;
         request.response.add(new Uint8List(64 * 1024));
@@ -195,7 +195,7 @@ void testHttpServerClientClose() {
           });
         });
       });
-    }, onError: (e, s) {
+    }, (e, s) {
       Expect.fail("Unexpected error: $e(${e.hashCode})\n$s");
     });
     var client = new HttpClient();

tests/standalone/io/raw_socket_test.dart

@@ -426,7 +426,7 @@ void testSocketZone() {
 void testSocketZoneError() {
   asyncStart();
   Expect.equals(Zone.root, Zone.current);
-  runZoned(() {
+  runZonedGuarded(() {
     Expect.notEquals(Zone.root, Zone.current);
     RawServerSocket.bind(InternetAddress.loopbackIPv4, 0).then((server) {
       Expect.notEquals(Zone.root, Zone.current);
@@ -451,7 +451,7 @@ void testSocketZoneError() {
         socket.close();
       });
     });
-  }, onError: (e) {
+  }, (e, s) {
     asyncEnd();
   });
 }

tests/standalone/io/wait_for_event_zone_caught_error_test.dart

@@ -17,12 +17,12 @@ main() {
   initWaitForEvent();
   asyncStart();
   bool flag = false;
-  runZoned(() {
+  runZonedGuarded(() {
     Timer.run(() {
       asyncEnd();
       throw "Exception";
     });
-  }, onError: (e) {
+  }, (e, s) {
     flag = true;
   });
   Expect.isFalse(flag);

tests/standalone/io/wait_for_exception_test.dart

@@ -11,12 +11,12 @@ import 'package:expect/expect.dart';
 main() {
   asyncStart();
   Completer<bool> c = new Completer<bool>();
-  runZoned(() {
+  runZonedGuarded(() {
     Timer.run(() {
       asyncEnd();
       throw "Error";
     });
-  }, onError: (e) {
+  }, (e, s) {
     Expect.isTrue(e is String);
     c.complete(true);
   });

tests/standalone_2/io/async_catch_errors_test.dart

@@ -12,11 +12,11 @@ var events = [];
 
 Future testSocketException() {
   var completer = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     Socket.connect("4", 1).then((Socket s) {
       Expect.fail("Socket should not be able to connect");
     });
-  }, onError: (err) {
+  }, (err, s) {
     if (err is! SocketException) Expect.fail("Not expected error: $err");
     completer.complete("socket test, ok.");
     events.add("SocketException");
@@ -26,9 +26,9 @@ Future testSocketException() {
 
 Future testFileSystemException() {
   var completer = new Completer();
-  runZoned(() {
+  runZonedGuarded(() {
     new File("lol it's not a file\n").openRead().listen(null);
-  }, onError: (err) {
+  }, (err, s) {
     if (err is! FileSystemException) Expect.fail("Not expected error: $err");
     completer.complete("file test, ok.");
     events.add("FileSystemException");

tests/standalone_2/io/file_system_watcher_test.dart

@@ -451,11 +451,11 @@ testWatchOverflow() async {
 }
 
 void watcher(SendPort sendPort) async {
-  runZoned(() {
+  runZonedGuarded(() {
     var watcher = Directory.systemTemp.watch(recursive: true);
     watcher.listen((data) async {});
     sendPort.send('start');
-  }, onError: (error) {
+  }, (error, stack) {
     print(error);
     sendPort.send('end');
   });

tests/standalone_2/io/http_server_test.dart

@@ -159,7 +159,7 @@ void testHttpServerZone() {
 void testHttpServerZoneError() {
   asyncStart();
   Expect.equals(Zone.root, Zone.current);
-  runZoned(() {
+  runZonedGuarded(() {
     Expect.notEquals(Zone.root, Zone.current);
     HttpServer.bind("127.0.0.1", 0).then((server) {
       Expect.notEquals(Zone.root, Zone.current);
@@ -178,14 +178,14 @@ void testHttpServerZoneError() {
         socket.listen(null);
       });
     });
-  }, onError: (e) {
+  }, (e, s) {
     asyncEnd();
   });
 }
 
 void testHttpServerClientClose() {
   HttpServer.bind("127.0.0.1", 0).then((server) {
-    runZoned(() {
+    runZonedGuarded(() {
       server.listen((request) {
         request.response.bufferOutput = false;
         request.response.add(new Uint8List(64 * 1024));
@@ -195,7 +195,7 @@ void testHttpServerClientClose() {
           });
         });
       });
-    }, onError: (e, s) {
+    }, (e, s) {
       Expect.fail("Unexpected error: $e(${e.hashCode})\n$s");
     });
     var client = new HttpClient();

tests/standalone_2/io/raw_socket_test.dart

@@ -429,7 +429,7 @@ void testSocketZone() {
 void testSocketZoneError() {
   asyncStart();
   Expect.equals(Zone.root, Zone.current);
-  runZoned(() {
+  runZonedGuarded(() {
     Expect.notEquals(Zone.root, Zone.current);
     RawServerSocket.bind(InternetAddress.loopbackIPv4, 0).then((server) {
       Expect.notEquals(Zone.root, Zone.current);
@@ -454,7 +454,7 @@ void testSocketZoneError() {
         socket.close();
       });
     });
-  }, onError: (e) {
+  }, (e, s) {
     asyncEnd();
   });
 }

tests/standalone_2/io/wait_for_event_zone_caught_error_test.dart

@@ -17,12 +17,12 @@ main() {
   initWaitForEvent();
   asyncStart();
   bool flag = false;
-  runZoned(() {
+  runZonedGuarded(() {
     Timer.run(() {
       asyncEnd();
       throw "Exception";
     });
-  }, onError: (e) {
+  }, (e, s) {
     flag = true;
   });
   Expect.isFalse(flag);

tests/standalone_2/io/wait_for_exception_test.dart

@@ -11,12 +11,12 @@ import 'package:expect/expect.dart';
 main() {
   asyncStart();
   Completer<bool> c = new Completer<bool>();
-  runZoned(() {
+  runZonedGuarded(() {
     Timer.run(() {
       asyncEnd();
       throw "Error";
     });
-  }, onError: (e) {
+  }, (e, s) {
     Expect.isTrue(e is String);
     c.complete(true);
   });