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packages/barback/test/transformer/bad.dart

Index: packages/barback/test/transformer/bad.dart
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+// 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 barback.test.transformer.bad;
+
+import 'package:barback/barback.dart';
+
+import 'mock.dart';
+
+/// A transformer that throws an exception when run, after generating the
+/// given outputs.
+class BadTransformer extends MockTransformer {
+  /// The error it throws.
+  static const ERROR = "I am a bad transformer!";
+
+  /// The list of asset names that it should output.
+  final List<String> outputs;
+
+  BadTransformer(this.outputs);
+
+  bool doIsPrimary(AssetId id) => true;
+
+  void doApply(Transform transform) {
+    // Create the outputs first.
+    for (var output in outputs) {
+      var id = new AssetId.parse(output);
+      transform.addOutput(new Asset.fromString(id, output));
+    }
+
+    // Then fail.
+    throw ERROR;
+  }
+}