Roll Observatory packages and add a roll script

packages/csslib/test/visitor_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 visitor_test;
+
+import 'package:csslib/visitor.dart';
+import 'package:test/test.dart';
+
+import 'testing.dart';
+
+class ClassVisitor extends Visitor {
+  final List expectedClasses;
+  final Set<String> foundClasses = new Set();
+
+  ClassVisitor(this.expectedClasses);
+
+  void visitClassSelector(ClassSelector node) {
+    foundClasses.add(node.name);
+  }
+
+  bool get matches {
+    bool match = true;
+    foundClasses.forEach((value) {
+      match = match && expectedClasses.contains(value);
+    });
+    expectedClasses.forEach((value) {
+      match = match && foundClasses.contains(value);
+    });
+
+    return match;
+  }
+}
+
+void testClassVisitors() {
+  var errors = [];
+  var in1 = '.foobar { }';
+
+  var s = parseCss(in1, errors: errors);
+
+  expect(s != null, true);
+  expect(errors.isEmpty, true, reason: errors.toString());
+
+  var clsVisits = new ClassVisitor(['foobar'])..visitTree(s);
+  expect(clsVisits.matches, true);
+
+  in1 = '''
+      .foobar1 { }
+      .xyzzy .foo #my-div { color: red; }
+      div.hello { font: arial; }
+    ''';
+
+  s = parseCss(in1, errors: errors..clear(), opts: simpleOptions);
+
+  expect(s != null, true);
+  expect(errors.isEmpty, true, reason: errors.toString());
+
+  clsVisits = new ClassVisitor(['foobar1', 'xyzzy', 'foo', 'hello'])
+    ..visitTree(s);
+  expect(clsVisits.matches, true);
+
+  expect(prettyPrint(s), r'''
+.foobar1 {
+}
+.xyzzy .foo #my-div {
+  color: #f00;
+}
+div.hello {
+  font: arial;
+}''');
+}
+
+class PolyfillEmitter extends CssPrinter {
+  final String _prefix;
+
+  PolyfillEmitter(this._prefix);
+
+  void visitClassSelector(ClassSelector node) {
+    emit('.${_prefix}_${node.name}');
+  }
+}
+
+String polyfillPrint(String prefix, StyleSheet ss) =>
+    (new PolyfillEmitter(prefix)..visitTree(ss, pretty: true)).toString();
+
+void testPolyFill() {
+  var errors = [];
+  final input = r'''
+.foobar { }
+div.xyzzy { }
+#foo .foo .bar .foobar { }
+''';
+
+  final generated = r'''
+.myComponent_foobar {
+}
+div.myComponent_xyzzy {
+}
+#foo .myComponent_foo .myComponent_bar .myComponent_foobar {
+}''';
+
+  var s = parseCss(input, errors: errors);
+  expect(s != null, true);
+  expect(errors.isEmpty, true, reason: errors.toString());
+
+  final emitted = polyfillPrint('myComponent', s);
+  expect(emitted, generated);
+}
+
+main() {
+  test('Class Visitors', testClassVisitors);
+  test('Polyfill', testPolyFill);
+}