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packages/csslib/test/testing.dart

+// Copyright (c) 2012, 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.
+
+/** Common definitions used for setting up the test environment. */
+library testing;
+
+import 'package:csslib/parser.dart';
+import 'package:csslib/visitor.dart';
+import 'package:csslib/src/messages.dart';
+import 'package:csslib/src/options.dart';
+
+export 'package:csslib/src/options.dart';
+
+const simpleOptionsWithCheckedAndWarningsAsErrors = const PreprocessorOptions(
+    useColors: false,
+    checked: true,
+    warningsAsErrors: true,
+    inputFile: 'memory');
+
+const simpleOptions =
+    const PreprocessorOptions(useColors: false, inputFile: 'memory');
+
+const options = const PreprocessorOptions(
+    useColors: false, warningsAsErrors: true, inputFile: 'memory');
+
+/**
+ * Spin-up CSS parser in checked mode to detect any problematic CSS.  Normally,
+ * CSS will allow any property/value pairs regardless of validity; all of our
+ * tests (by default) will ensure that the CSS is really valid.
+ */
+StyleSheet parseCss(String cssInput,
+    {List<Message> errors, PreprocessorOptions opts}) => parse(cssInput,
+        errors: errors,
+        options: opts == null
+            ? simpleOptionsWithCheckedAndWarningsAsErrors
+            : opts);
+
+/**
+ * Spin-up CSS parser in checked mode to detect any problematic CSS.  Normally,
+ * CSS will allow any property/value pairs regardless of validity; all of our
+ * tests (by default) will ensure that the CSS is really valid.
+ */
+StyleSheet compileCss(String cssInput, {List<Message> errors,
+    PreprocessorOptions opts, bool polyfill: false,
+    List<StyleSheet> includes: null}) => compile(cssInput,
+        errors: errors,
+        options: opts == null
+            ? simpleOptionsWithCheckedAndWarningsAsErrors
+            : opts,
+        polyfill: polyfill,
+        includes: includes);
+
+StyleSheet polyFillCompileCss(input,
+        {List<Message> errors, PreprocessorOptions opts}) =>
+    compileCss(input, errors: errors, polyfill: true, opts: opts);
+
+/** CSS emitter walks the style sheet tree and emits readable CSS. */
+final _emitCss = new CssPrinter();
+
+/** Simple Visitor does nothing but walk tree. */
+final _cssVisitor = new Visitor();
+
+/** Pretty printer for CSS. */
+String prettyPrint(StyleSheet ss) {
+  // Walk the tree testing basic Vistor class.
+  walkTree(ss);
+  return (_emitCss..visitTree(ss, pretty: true)).toString();
+}
+
+/**
+ * Helper function to emit compact (non-pretty printed) CSS for suite test
+ * comparsions.  Spaces, new lines, etc. are reduced for easier comparsions of
+ * expected suite test results.
+ */
+String compactOuptut(StyleSheet ss) {
+  walkTree(ss);
+  return (_emitCss..visitTree(ss, pretty: false)).toString();
+}
+
+/** Walks the style sheet tree does nothing; insures the basic walker works. */
+void walkTree(StyleSheet ss) {
+  _cssVisitor..visitTree(ss);
+}
+
+String dumpTree(StyleSheet ss) => treeToDebugString(ss);