Reduce test.dart memory usage

tools/testing/dart/test_suite.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.
 
 /**
  * Classes and methods for enumerating and preparing tests.
  *
  * This library includes:
  *
  * - Creating tests by listing all the Dart files in certain directories,
@@ skipping 242 matching lines @@
   //  - update SummaryReport
   //  - handle SKIP/SKIP_BY_DESIGN markers
   //  - test if the selector matches
   // and will enqueue the test (if necessary).
   void enqueueNewTestCase(TestCase testCase) {
     var expectations = testCase.expectedOutcomes;
 
     // Handle sharding based on the original test path (i.e. all multitests
     // of a given original test belong to the same shard)
     int shards = configuration['shards'];
-    if (shards > 1) {
-      int shard = configuration['shard'];
-      var testPath =
-          testCase.info.originTestPath.relativeTo(TestUtils.dartDir);
-      if ("$testPath".hashCode % shards != shard - 1) {
-        return;
-      }
+    if (shards > 1 && testCase.hash % shards != configuration['shard'] - 1) {
+      return;
     }
     // Test if the selector includes this test.
     RegExp pattern = configuration['selectors'][suiteName];
     if (!pattern.hasMatch(testCase.displayName)) {
       return;
     }
 
     // Update Summary report
     if (configuration['report']) {
       SummaryReport.add(expectations);
-      if (testCase.info != null &&
-          testCase.expectCompileError &&
+      if (testCase.expectCompileError &&
           TestUtils.isBrowserRuntime(configuration['runtime']) &&
           new CompilerConfiguration(configuration).hasCompiler) {
         SummaryReport.addCompileErrorSkipTest();
         return;
       }
     }
 
     // Handle skipped tests
     if (expectations.contains(Expectation.SKIP) ||
         expectations.contains(Expectation.SKIP_BY_DESIGN)) {
@@ skipping 204 matching lines @@
  * The tests are compiled into a monolithic executable by the build step.
  * The executable lists its tests when run with the --list command line flag.
  * Individual tests are run by specifying them on the command line.
  */
 class CCTestSuite extends TestSuite {
   final String testPrefix;
   String targetRunnerPath;
   String hostRunnerPath;
   final String dartDir;
   List<String> statusFilePaths;
-  VoidFunction doDone;
 
   CCTestSuite(Map configuration,
               String suiteName,
               String runnerName,
               this.statusFilePaths,
               {this.testPrefix: ''})
       : super(configuration, suiteName),
         dartDir = TestUtils.dartDir.toNativePath() {
     // For running the tests we use the given '$runnerName' binary
     targetRunnerPath = '$buildDir/$runnerName';
@@ skipping 21 matching lines @@
     args.add(testName);
 
     var command = CommandBuilder.instance.getProcessCommand(
         'run_vm_unittest', targetRunnerPath, args, environmentOverrides);
     enqueueNewTestCase(
         new TestCase(constructedName, [command], configuration, expectations));
   }
 
   void forEachTest(Function onTest, Map testCache, [VoidFunction onDone]) {
     doTest = onTest;
-    doDone = onDone;
-
     var statusFiles =
         statusFilePaths.map((statusFile) => "$dartDir/$statusFile").toList();
 
     ReadTestExpectations(statusFiles, configuration)
         .then((TestExpectations expectations) {
       ccTestLister(hostRunnerPath).then((Iterable<String> names) {
         names.forEach((testName) => testNameHandler(expectations, testName));
-        onDone();
+        doTest = null;
+        if (onDone != null) onDone();
       }).catchError((error) {
         print("Fatal error occured: $error");
         exit(1);
       });
     });
   }
 }
 
 
 class TestInformation {
@@ skipping 1235 matching lines @@
 
         // Enqueue TestCase
         var testCase = new TestCase(displayName,
             commands, configuration, testExpectations.expectations(testName));
         enqueueNewTestCase(testCase);
       }
 
       localPackageDirectories.forEach(enqueueTestCase);
       localSampleDirectories.forEach(enqueueTestCase);
 
+      doTest = null;
       // Notify we're done
       if (onDone != null) onDone();
     }
 
     doTest = onTest;
     Map<String, String> _localPackageDirectories;
     Map<String, String> _localSampleDirectories;
     List<String> statusFiles = [
         TestUtils.dartDir.join(new Path(statusFilePath)).toNativePath()];
     ReadTestExpectations(statusFiles, configuration).then((expectations) {
@@ skipping 393 matching lines @@
  * $pass tests are expected to pass
  * $failOk tests are expected to fail that we won't fix
  * $fail tests are expected to fail that we should fix
  * $crash tests are expected to crash that we should fix
  * $timeout tests are allowed to timeout
  * $compileErrorSkip tests are skipped on browsers due to compile-time error
 """;
     print(report);
   }
 }