Make isolate tests work on drt (and hopefully dartium).

tests/isolate/remote_unittest_helper.dart

+// 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.
+
+// Helper functions and classes for running a set of unittests in a
+// remote isolate.
+// Used to test Isolate.spawn because dartium/drt does not allow it in the DOM
+// isolate.
+
+import "dart:isolate";
+import "package:unittest/unittest.dart";
+import "dart:mirrors";
+
+/**
+ * Use this function at the beginning of the main method:
+ *
+ *     void main([args, port]) {
+ *       if (testRemote(main, port)) return;
+ *       // the usual test.
+ *     }
+ */

[siva, 2013/11/14 17:21:08]

I find this a little tricky, you probably did it this way to minimize changes to
the tests.

Why not instead go with this scheme for all isolate tests:

existing main becomes testMain
new main would be:
void main([args, port]) {
  return testInNewIsolate(testMain, [args, port]);
}

Your current testRemote could be renamed to testInNewIsolate with the signature
also accepting 'args'.

the catch part in LocalTests.run would have to be changed to:
} catch (e) {
  // ....
  // ....
  return Function.apply(main, [args, port]);
}

[Lasse Reichstein Nielsen, 2013/11/15 14:57:45]

Minimizing changes was a goal, yes :) Didn't succeed as well as I had hoped,
since I had to convert some tests to using the unittest package.

I could pass testMain instead of main to the function, and have the function
call testMain directly instead of returning a bool. I'm not sure it's much
simpler.

I use "main" because it guarantees that its library is the correct library to
rerun the "main" function of (by spawnUri). If I used "testMain" as argument,
I'd have to document that it had to be in the same library as "main" (which it
always would be for these fairly simple tests, but still, it's more fragile).

+bool testRemote(Function main, SendPort port) {
+  if (port == null) {
+    return new LocalTests().run(main);
+  } else {
+    unittestConfiguration = new RemoteConfiguration(port);
+    return false;
+  }
+}
+
+
+class LocalTests {
+  final ReceivePort _port = new ReceivePort();
+  final Map<String, Function> _testBody = new Map<String, Function>();
+
+  bool run(Function main) {
+    ClosureMirror closure = reflect(main);
+    LibraryMirror library = closure.function.owner;
+    try {
+      Isolate.spawnUri(library.uri, null, _port.sendPort);
+      _port.listen(remoteAction);
+      return true;
+    } catch (e) {
+      // spawnUri is only supported by dart2js if web workers are available.
+      // If the spawnUri fails, run the tests locally instead, since we are
+      // not in a browser anyway.
+      return false;
+    }
+  }
+
+  void remoteAction(message) {
+    switch (message[0]) {
+      case "testStart":
+        String name = message[1];
+        test(name, () {
+          _testBody[name] = expectAsync2((result, message) {
+            if (result == FAIL) {
+              fail(message);
+            } else if (result == ERROR) {
+              throw message;
+            }
+            _testBody.remove(name);
+          });
+        });
+        break;
+      case "testResult":
+        String name = message[1];
+        Function completer = _testBody[name];
+        completer(message[2], message[3]);
+        break;
+      case "testResultChanged":
+        throw new UnsupportedError("result change after the fact?");
+      case "logMessage":
+        break;  // Ignore.
+      case "summary":
+        throw message[1];  // Uncaught error.
+      case "done":
+        _port.close();
+        break;
+    }
+  }
+}
+
+
+class RemoteConfiguration implements Configuration {
+  final SendPort _port;
+  Duration timeout = const Duration(minutes: 2);
+
+  RemoteConfiguration(this._port);
+
+  bool get autoStart => true;
+
+  void onInit() { }
+
+  void onStart() { }
+
+  void onTestStart(TestCase testCase) {
+    _port.send(["testStart", testCase.description]);
+  }
+
+  void onTestResult(TestCase testCase) {
+    _port.send(["testResult", testCase.description,
+                testCase.result, testCase.message]);
+  }
+
+  void onTestResultChanged(TestCase testCase) {
+    _port.send(["testResultChanged", testCase.description,
+                testCase.result, testCase.message]);
+  }
+
+  void onLogMessage(TestCase testCase, String message) {
+    _port.send(["logMessage", testCase.description, message]);
+  }
+
+  void onDone(bool success) {
+    _port.send(["done", success]);
+  }
+
+  void onSummary(int passed, int failed, int errors, List<TestCase> results,
+      String uncaughtError) {
+    if (uncaughtError != null) {
+      _port.send(["summary", uncaughtError]);
+    }
+  }
+}