Move the addition of an onError handler to earlier (onInit instead of onStart), while still support…

pkg/unittest/interactive_html_config.dart

 // Copyright (c) 2012, 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.
 
 /**
  * This configuration can be used to rerun selected tests, as well
  * as see diagnostic output from tests. It runs each test in its own
  * IFrame, so the configuration consists of two parts - a 'parent'
  * config that manages all the tests, and a 'child' config for the
  * IFrame that runs the individual tests.
@@ skipping 33 matching lines @@
     ++idx;
     int idx2 = msg.indexOf(' ', idx);
     elapsed = int.parse(msg.substring(idx, idx2));
     ++idx2;
     body = msg.substring(idx2);
   }
 
   String toString() => text(messageType, elapsed, body);
 }
 
+
+class HtmlConfiguration extends Configuration {
+  // TODO(rnystrom): Get rid of this if we get canonical closures for methods.
+  EventListener _onErrorClosure;
+
+  void _installErrorHandler() {
+    if (_onErrorClosure == null) {
+      _onErrorClosure =
+          (e) => handleExternalError(e, '(DOM callback has errors)');
+      // Listen for uncaught errors.
+      window.on.error.add(_onErrorClosure);
+    }
+  }
+
+  void _uninstallErrorHandler() {
+    if (_onErrorClosure != null) {
+      window.on.error.remove(_onErrorClosure);
+      _onErrorClosure = null;
+    }
+  }
+}
+
 /**
  * The child configuration that is used to run individual tests in
  * an IFrame and post the results back to the parent. In principle
  * this can run more than one test in the IFrame but currently only
  * one is used.
  */
-class ChildInteractiveHtmlConfiguration extends Configuration {
-  // TODO(rnystrom): Get rid of this if we get canonical closures for methods.
-  EventListener _onErrorClosure;
+class ChildInteractiveHtmlConfiguration extends HtmlConfiguration {
 
   /** The window to which results must be posted. */
   Window parentWindow;
 
   /** The time at which tests start. */
   Map<int,Date> _testStarts;
 
   ChildInteractiveHtmlConfiguration() :
       _testStarts = new Map<int,Date>();
 
   /** Don't start running tests automatically. */
   get autoStart => false;
 
   void onInit() {
-    _onErrorClosure =
-        (e) => handleExternalError(e, '(DOM callback has errors)');
+    _installErrorHandler();
 
     /**
      *  The parent posts a 'start' message to kick things off,
      *  which is handled by this handler. It saves the parent
      *  window, gets the test ID from the query parameter in the
      *  IFrame URL, sets that as a solo test and starts test execution.
      */
     window.on.message.add((MessageEvent e) {
       // Get the result, do any logging, then do a pass/fail.
       var m = new _Message.fromString(e.data);
       if (m.messageType == _Message.START) {
         parentWindow = e.source;
         String search = window.location.search;
         int pos = search.indexOf('t=');
         String ids = search.substring(pos+2);
         int id = int.parse(ids);
         setSoloTest(id);
         runTests();
       }
     });
   }
 
   void onStart() {
-    // Listen for uncaught errors.
-    window.on.error.add(_onErrorClosure);
+    _installErrorHandler();
   }
 
   /** Record the start time of the test. */
   void onTestStart(TestCase testCase) {
     super.onTestStart(testCase);
     _testStarts[testCase.id]= new Date.now();
   }
 
   /**
    * Tests can call [logMessage] for diagnostic output. These log
@@ skipping 24 matching lines @@
     if (testCase.stackTrace != null) {
       parentWindow.postMessage(
           _Message.text(_Message.STACK, elapsed, testCase.stackTrace), '*');
     }
     parentWindow.postMessage(
         _Message.text(testCase.result, elapsed, testCase.message), '*');
   }
 
   void onDone(int passed, int failed, int errors, List<TestCase> results,
               String uncaughtError) {
-    window.on.error.remove(_onErrorClosure);
+    _uninstallErrorHandler();
   }
 }
 
 /**
  * The parent configuration runs in the top-level window; it wraps the tests
  * in new functions that create child IFrames and run the real tests.
  */
-class ParentInteractiveHtmlConfiguration extends Configuration {
+class ParentInteractiveHtmlConfiguration extends HtmlConfiguration {
   Map<int,Date> _testStarts;
-  // TODO(rnystrom): Get rid of this if we get canonical closures for methods.
-  EventListener _onErrorClosure;
+
 
   /** The stack that was posted back from the child, if any. */
   String _stack;
 
   int _testTime;
   /**
    * Whether or not we have already wrapped the TestCase test functions
    * in new closures that instead create an IFrame and get it to run the
    * test.
    */
@@ skipping 46 matching lines @@
       } else if (msg.messageType == _Message.FAIL) {
         currentTestCase.fail(msg.body, _stack);
       } else if (msg.messageType == _Message.ERROR) {
         currentTestCase.error(msg.body, _stack);
       }
       completeTest();
     }
   }
 
   void onInit() {
+    _installErrorHandler();
     _messageHandler = _handleMessage; // We need to make just one closure.
-    _onErrorClosure =
-        (e) => handleExternalError(e, '(DOM callback has errors)');
     document.query('#group-divs').innerHTML = "";
   }
 
   void onStart() {
-    // Listen for uncaught errors.
-    window.on.error.add(_onErrorClosure);
+    _installErrorHandler();
     if (!_doneWrap) {
       _doneWrap = true;
       for (int i = 0; i < testCases.length; i++) {
         testCases[i].test = wrapTest(testCases[i]);
         testCases[i].setUp = null;
         testCases[i].tearDown = null;
       }
     }
     window.on.message.add(_messageHandler);
   }
@@ skipping 143 matching lines @@
     var actions = testItem.query('.test-actions');
     for (Element e in actions.nodes) {
       e.classes.add(result);
     }
     actions.style.display = 'none';
   }
 
   void onDone(int passed, int failed, int errors, List<TestCase> results,
       String uncaughtError) {
     window.on.message.remove(_messageHandler);
-    window.on.error.remove(_onErrorClosure);
+    _uninstallErrorHandler();
     document.query('#busy').style.display = 'none';
     InputElement startButton = document.query('#start');
     startButton.disabled = false;
   }
 }
 
 /**
  * Add the divs to the DOM if they are not present. We have a 'controls'
  * div for control, 'specs' div with test results, a 'busy' div for the
  * animated GIF used to indicate tests are running, and a 'child' div to
@@ skipping 240 matching lines @@
 display: block;
 list-style-type: disc;
 -webkit-margin-before: 1em;
 -webkit-margin-after: 1em;
 -webkit-margin-start: 0px;
 -webkit-margin-end: 0px;
 -webkit-padding-start: 40px;
 }
 
   """;