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packages/barback/test/transformer/declaring_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.declaring_bad;
+
+import 'package:barback/barback.dart';
+
+import 'bad.dart';
+import 'mock.dart';
+
+/// A transformer that throws an exception when run, after generating the
+/// given outputs.
+class DeclaringBadTransformer extends MockTransformer
+    implements DeclaringTransformer {
+  /// Whether this should throw an error in [declareOutputs].
+  final bool declareError;
+
+  /// Whether this should throw an error in [apply].
+  final bool applyError;
+
+  /// The id of the output asset to emit.
+  final AssetId output;
+
+  DeclaringBadTransformer(String output, {bool declareError: true,
+          bool applyError: false})
+      : this.output = new AssetId.parse(output),
+        this.declareError = declareError,
+        this.applyError = applyError;
+
+  bool doIsPrimary(AssetId id) => true;
+
+  void doApply(Transform transform) {
+    transform.addOutput(new Asset.fromString(output, "bad out"));
+    if (applyError) throw BadTransformer.ERROR;
+  }
+
+  void declareOutputs(DeclaringTransform transform) {
+    if (consumePrimary) transform.consumePrimary();
+    transform.declareOutput(output);
+    if (declareError) throw BadTransformer.ERROR;
+  }
+}