Simplify CommandOutput and friends.

tools/testing/dart/command.dart

 // Copyright (c) 2017, 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.
 
 import 'dart:async';
 // We need to use the 'io' prefix here, otherwise io.exitCode will shadow
 // CommandOutput.exitCode in subclasses of CommandOutput.
 import 'dart:io' as io;
 
 import 'command_output.dart';
@@ skipping 219 matching lines @@
       this._alwaysCompile,
       this._bootstrapDependencies,
       String executable,
       List<String> arguments,
       Map<String, String> environmentOverrides)
       : super._(displayName, executable, arguments, environmentOverrides);
 
   bool get outputIsUpToDate {
     if (_alwaysCompile) return false;
 
-    List<Uri> readDepsFile(String path) {
-      var file = new io.File(new Path(path).toNativePath());
-      if (!file.existsSync()) return null;
+    var file = new io.File(new Path("$_outputFile.deps").toNativePath());
+    if (!file.existsSync()) return false;
 
-      var lines = file.readAsLinesSync();
-      var dependencies = <Uri>[];
-      for (var line in lines) {
-        line = line.trim();
-        if (line.isNotEmpty) {
-          dependencies.add(Uri.parse(line));
-        }
+    var lines = file.readAsLinesSync();
+    var dependencies = <Uri>[];
+    for (var line in lines) {
+      line = line.trim();
+      if (line.isNotEmpty) {
+        dependencies.add(Uri.parse(line));
       }
-
-      return dependencies;
     }
 
-    var dependencies = readDepsFile("$_outputFile.deps");
-    if (dependencies == null) return false;
-
     dependencies.addAll(_bootstrapDependencies);
     var jsOutputLastModified = TestUtils.lastModifiedCache
         .getLastModified(new Uri(scheme: 'file', path: _outputFile));
     if (jsOutputLastModified == null) return false;
 
     for (var dependency in dependencies) {
       var dependencyLastModified =
           TestUtils.lastModifiedCache.getLastModified(dependency);
       if (dependencyLastModified == null ||
           dependencyLastModified.isAfter(jsOutputLastModified)) {
@@ skipping 236 matching lines @@
   }
 
   bool _equal(PubCommand other) =>
       super._equal(other) && command == other.command;
 }
 
 /// [ScriptCommand]s are executed by dart code.
 abstract class ScriptCommand extends Command {
   ScriptCommand._(String displayName) : super._(displayName);
 
-  Future<ScriptCommandOutputImpl> run();
+  Future<ScriptCommandOutput> run();
 }
 
 class CleanDirectoryCopyCommand extends ScriptCommand {
   final String _sourceDirectory;
   final String _destinationDirectory;
 
   CleanDirectoryCopyCommand._(this._sourceDirectory, this._destinationDirectory)
       : super._('dir_copy');
 
   String get reproductionCommand =>
       "Copying '$_sourceDirectory' to '$_destinationDirectory'.";
 
-  Future<ScriptCommandOutputImpl> run() {
+  Future<ScriptCommandOutput> run() {
     var watch = new Stopwatch()..start();
 
     var destination = new io.Directory(_destinationDirectory);
 
     return destination.exists().then((bool exists) {
       Future cleanDirectoryFuture;
       if (exists) {
         cleanDirectoryFuture = TestUtils.deleteDirectory(_destinationDirectory);
       } else {
         cleanDirectoryFuture = new Future.value(null);
       }
       return cleanDirectoryFuture.then((_) {
         return TestUtils.copyDirectory(_sourceDirectory, _destinationDirectory);
       });
     }).then((_) {
-      return new ScriptCommandOutputImpl(
-          this, Expectation.pass, "", watch.elapsed);
+      return new ScriptCommandOutput(this, Expectation.pass, "", watch.elapsed);
     }).catchError((error) {
-      return new ScriptCommandOutputImpl(
+      return new ScriptCommandOutput(
           this, Expectation.fail, "An error occured: $error.", watch.elapsed);
     });
   }
 
   void _buildHashCode(HashCodeBuilder builder) {
     super._buildHashCode(builder);
     builder.addJson(_sourceDirectory);
     builder.addJson(_destinationDirectory);
   }
 
   bool _equal(CleanDirectoryCopyCommand other) =>
       super._equal(other) &&
       _sourceDirectory == other._sourceDirectory &&
       _destinationDirectory == other._destinationDirectory;
 }
 
 /// Makes a symbolic link to another directory.
 class MakeSymlinkCommand extends ScriptCommand {
   String _link;
   String _target;
 
   MakeSymlinkCommand._(this._link, this._target) : super._('make_symlink');
 
   String get reproductionCommand =>
       "Make symbolic link '$_link' (target: $_target)'.";
 
-  Future<ScriptCommandOutputImpl> run() {
+  Future<ScriptCommandOutput> run() {
     var watch = new Stopwatch()..start();
     var targetFile = new io.Directory(_target);
     return targetFile.exists().then((bool targetExists) {
       if (!targetExists) {
         throw new Exception("Target '$_target' does not exist");
       }
       var link = new io.Link(_link);
 
       return link.exists().then((bool exists) {
         if (exists) return link.delete();
       }).then((_) => link.create(_target));
     }).then((_) {
-      return new ScriptCommandOutputImpl(
-          this, Expectation.pass, "", watch.elapsed);
+      return new ScriptCommandOutput(this, Expectation.pass, "", watch.elapsed);
     }).catchError((error) {
-      return new ScriptCommandOutputImpl(
+      return new ScriptCommandOutput(
           this, Expectation.fail, "An error occured: $error.", watch.elapsed);
     });
   }
 
   void _buildHashCode(HashCodeBuilder builder) {
     super._buildHashCode(builder);
     builder.addJson(_link);
     builder.addJson(_target);
   }
 
   bool _equal(MakeSymlinkCommand other) =>
       super._equal(other) && _link == other._link && _target == other._target;
 }