Cache the tests across configurations in the test scripts.

tools/testing/dart/test_runner.dart

 // Copyright (c) 2011, 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("test_runner");
 
 #import("status_file_parser.dart");
 #import("test_progress.dart");
 #import("test_suite.dart");
 
@@ skipping 309 matching lines @@
 class ProcessQueue {
   int _numProcesses = 0;
   int _activeTestListers = 0;
   int _maxProcesses;
   bool _verbose;
   Function _enqueueMoreWork;
   Queue<TestCase> _tests;
   ProgressIndicator _progress;
   // For dartc batch processing we keep a list of batch processes.
   List<DartcBatchRunnerProcess> _batchProcesses;
+  // Cache information about test cases per test suite. For multiple
+  // configurations there is no need to repeatedly search the file
+  // system, generate tests, and search test files for options.
+  Map<String, List<TestInformation>> _testCache;
 
   ProcessQueue(int this._maxProcesses,
                String progress,
                bool this._verbose,
                Date startTime,
                bool printTiming,
                Function this._enqueueMoreWork)
       : _tests = new Queue<TestCase>(),
         _progress = new ProgressIndicator.fromName(progress,
                                                    startTime,
                                                    printTiming),
-        _batchProcesses = new List<DartcBatchRunnerProcess>() {
+        _batchProcesses = new List<DartcBatchRunnerProcess>(),
+        _testCache = new Map<String, List<TestInformation>>() {
     if (!_enqueueMoreWork(this)) _progress.allDone();
   }
 
   void addTestSuite(TestSuite testSuite) {
     _activeTestListers++;
-    testSuite.forEachTest(_runTest, _testListerDone);
+    testSuite.forEachTest(_runTest, _testCache, _testListerDone);
   }
 
   void _testListerDone() {
     _activeTestListers--;
     _checkDone();
   }
 
   void _checkDone() {
     // When there are no more active test listers ask for more work
     // from process queue users.
@@ skipping 49 matching lines @@
       if (test.configuration['component'] == 'dartc') {
         _ensureDartcBatchRunnersStarted(test.executablePath);
         _getDartcBatchRunnerProcess().startTest(test);
       } else {
         new RunningProcess(test).start();
       }
       _numProcesses++;
     }
   }
 }