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packages/barback/test/transformer/lazy_bad.dart

+// 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.lazy_bad;
+
+import 'package:barback/barback.dart';
+
+import 'mock.dart';
+
+/// A lazy transformer that throws an exception after [declareOutputs].
+class LazyBadTransformer extends MockTransformer implements LazyTransformer {
+  /// The error [this] throws.
+  static const ERROR = "I am a bad transformer!";
+
+  /// The asset name that [this] should output.
+  final String output;
+
+  LazyBadTransformer(this.output);
+
+  bool doIsPrimary(AssetId id) => true;
+
+  void doApply(Transform transform) {
+    var id = new AssetId.parse(output);
+    transform.addOutput(new Asset.fromString(id, output));
+  }
+
+  void declareOutputs(DeclaringTransform transform) {
+    var id = new AssetId.parse(output);
+    transform.declareOutput(id);
+    throw ERROR;
+  }
+}