Display metadata about out-of-band callbacks in scheduled test errors.

pkg/scheduled_test/lib/scheduled_process.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.
 
 library scheduled_process;
 
 import 'dart:async';
 import 'dart:io';
 
 import 'scheduled_test.dart';
@@ skipping 154 matching lines @@
         // to complete and pump the event queue so that _endExpected will be
         // set.
         return _taskBeforeEnd.result.then((_) => pumpEventQueue());
       }).then((_) {
         exitCodeCompleter.complete(exitCode);
 
         if (!_endExpected) {
           throw "Process '${this.description}' ended earlier than scheduled "
             "with exit code $exitCode.";
         }
-      }));
+      }), "waiting to reach shouldExit() or kill() for process "
+          "'${this.description}'");

[Bob Nystrom, 2013/03/12 20:08:51]

Is "this." still needed here (and above)?

[nweiz, 2013/03/12 20:56:51]

Nope. Done.

     });
   }
 
   /// Converts a stream of bytes to a stream of lines and returns that along
   /// with a [StreamCanceller] controlling it.
   Pair<Stream<String>, StreamCanceller> _lineStreamWithCanceller(
       Future<Stream<int>> streamFuture) {
     return streamWithCanceller(futureStream(streamFuture)
         .handleError((e) => currentSchedule.signalError(e))
         .transform(new StringDecoder(_encoding))
         .transform(new LineTransformer()));
   }
 
   /// Schedule an exception handler that will clean up the process and provide
   /// debug information if an error occurs.
   void _scheduleExceptionCleanup() {
     currentSchedule.onException.schedule(() {
       _stdoutCanceller();
       _stderrCanceller();
 
       if (!_process.hasValue) return;
 
       var killedPrematurely = false;
       if (!_exitCode.hasValue) {
         killedPrematurely = true;
         _endExpected = true;
         _process.value.kill();
         // Ensure that the onException queue waits for the process to actually
         // exit after being killed.
-        wrapFuture(_process.value.exitCode);
+        wrapFuture(_process.value.exitCode, "waiting for process "
+            "'${this.description}' to die");

[Bob Nystrom, 2013/03/12 20:08:51]

Ditto.

[nweiz, 2013/03/12 20:56:51]

Done.

       }
 
       return Future.wait([
         _stdoutLog.toList(),
         _stderrLog.toList()
       ]).then((results) {
         var stdout = results[0].join("\n");
         var stderr = results[1].join("\n");
 
         var exitDescription = killedPrematurely
@@ skipping 81 matching lines @@
     schedule(() {
       _endExpected = true;
       return _exitCode.then((exitCode) {
         if (expectedExitCode != null) {
           expect(exitCode, equals(expectedExitCode));
         }
       });
     }, "waiting for process '$description' to exit");
   }
 }