Enable the "skip command compilation if output is already up-to-date" feature in dart2dart

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 687 matching lines @@
   }
 
   List<Command> makeCommands(TestInformation info, var vmOptions, var args) {
     switch (configuration['compiler']) {
     case 'dart2js':
       args = new List.from(args);
       String tempDir = createOutputDirectory(info.filePath, '');
       args.add('--out=$tempDir/out.js');
 
        List<Command> commands = 
-           <Command>[new Dart2JsCommand("$tempDir/out.js",
-                                        !useDart2JsFromSdk,
-                                        dart2JsBootstrapDependencies,
-                                        compilerPath,
-                                        args)];
+           <Command>[new CompilationCommand("$tempDir/out.js",
+                                            !useDart2JsFromSdk,
+                                            dart2JsBootstrapDependencies,
+                                            compilerPath,
+                                            args)];
       if (info.hasCompileError) {
         // Do not attempt to run the compiled result. A compilation
         // error should be reported by the compilation command.
       } else if (configuration['runtime'] == 'd8') {
         commands.add(new Command(d8FileName, ['$tempDir/out.js']));
       } else if (configuration['runtime'] == 'jsshell') {
         commands.add(new Command(jsShellFileName, ['$tempDir/out.js']));
       }
       return commands;
 
     case 'dart2dart':
-      var compilerArguments = new List.from(args);
-      compilerArguments.add('--output-type=dart');
+      args = new List.from(args);
+      args.add('--output-type=dart');
       String tempDir = createOutputDirectory(info.filePath, '');
-      compilerArguments.add('--out=$tempDir/out.dart');
+      args.add('--out=$tempDir/out.dart');
+
       List<Command> commands =
-          <Command>[new Command(compilerPath, compilerArguments)];
+          <Command>[new CompilationCommand("$tempDir/out.dart",
+                                           !useDart2JsFromSdk,
+                                           dart2JsBootstrapDependencies,
+                                           compilerPath,
+                                           args)];
       if (info.hasCompileError) {
         // Do not attempt to run the compiled result. A compilation
         // error should be reported by the compilation command.
       } else if (configuration['runtime'] == 'vm') {
         // TODO(antonm): support checked.
         var vmArguments = new List.from(vmOptions);
         vmArguments.addAll([
             '--ignore-unrecognized-flags', '$tempDir/out.dart']);
         commands.add(new Command(vmFileName, vmArguments));
       } else {
@@ skipping 271 matching lines @@
         args.add(inputFile);
         break;
       default:
         Expect.fail('unimplemented compiler $compiler');
     }
     if (executable.endsWith('.dart')) {
       // Run the compiler script via the Dart VM.
       args.insertRange(0, 1, executable);
       executable = dartShellFileName;
     }
-    if (configuration['compiler'] == 'dart2js') {
-      return new Dart2JsCommand(outputFile,
-                                !useDart2JsFromSdk,
-                                dart2JsBootstrapDependencies,
-                                compilerPath,
-                                args);
+    if (['dart2js', 'dart2dart'].contains(configuration['compiler'])) {
+      return new CompilationCommand(outputFile,
+                                   !useDart2JsFromSdk,
+                                   dart2JsBootstrapDependencies,
+                                   compilerPath,
+                                   args);
     }
     return new Command(executable, args);
   }
 
   /**
    * Create a directory for the generated test.  If a Dart language test
    * needs to be run in a browser, the Dart test needs to be embedded in
    * an HTML page, with a testing framework based on scripting and DOM events.
    * These scripts and pages are written to a generated_test directory
    * inside the build directory of the checkout.
@@ skipping 719 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);
    }
 }