Roll Observatory packages and add a roll script

packages/barback/test/package_graph/repetition_test.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.package_graph.transform_test;
+
+import 'package:barback/src/utils.dart';
+import 'package:scheduled_test/scheduled_test.dart';
+
+import '../utils.dart';
+
+// This tests the behavior of barback under many operations happening in quick
+// succession. Since Barback is so asynchronous, it's easy for it to have subtle
+// dependencies on the commonly-used and -tested usage patterns. These tests
+// exist to stress-test less-common usage patterns in order to root out
+// additional bugs.
+
+main() {
+  initConfig();
+
+  test("updates sources many times", () {
+    initGraph(["app|foo.txt"], {
+      "app": [[new RewriteTransformer("txt", "out")]]
+    });
+
+    for (var i = 0; i < 1000; i++) {
+      updateSources(["app|foo.txt"]);
+    }
+
+    expectAsset("app|foo.out", "foo.out");
+    buildShouldSucceed();
+  });
+
+  test("updates and then removes sources many times", () {
+    initGraph(["app|foo.txt"], {
+      "app": [[new RewriteTransformer("txt", "out")]]
+    });
+
+    for (var i = 0; i < 1000; i++) {
+      updateSources(["app|foo.txt"]);
+      removeSources(["app|foo.txt"]);
+    }
+
+    expectNoAsset("app|foo.out");
+    expectNoAsset("app|foo.txt");
+    buildShouldSucceed();
+  });
+
+  test("updates transformers many times", () {
+    var rewrite = new RewriteTransformer("txt", "out");
+    initGraph(["app|foo.txt"], {"app": [[rewrite]]});
+    updateSources(["app|foo.txt"]);
+
+    for (var i = 0; i < 1000; i++) {
+      updateTransformers("app", [[rewrite]]);
+    }
+
+    expectAsset("app|foo.out", "foo.out");
+    buildShouldSucceed();
+  });
+
+  test("updates and removes transformers many times", () {
+    var rewrite = new RewriteTransformer("txt", "out");
+    initGraph(["app|foo.txt"], {"app": [[rewrite]]});
+    updateSources(["app|foo.txt"]);
+
+    for (var i = 0; i < 1000; i++) {
+      updateTransformers("app", [[rewrite]]);
+      updateTransformers("app", [[]]);
+    }
+
+    expectAsset("app|foo.txt", "foo");
+    expectNoAsset("app|foo.out");
+    buildShouldSucceed();
+  });
+}