adding HtmlEscape to dart:convert

tests/lib/convert/html_escape_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.
+
+import "package:expect/expect.dart";
+import 'dart:async';
+import 'dart:convert';
+
+const _NOOP = 'Nothing_to_escape';
+
+const _TEST_INPUT = '<A <test> of \u00A0 "double" & \'single\' values>';
+
+const _OUTPUT_UNKNOWN = '&lt;A &lt;test&gt; of &nbsp; &quot;double&quot; &amp; '
+  '&apos;single&apos; values&gt;';
+
+const _OUTPUT_ATTRIBUTE = "<A <test> of &nbsp; &quot;double&quot; &amp; "
+  "\'single\' values>";
+
+const _OUTPUT_ELEMENT = '&lt;A &lt;test&gt; of &nbsp; "double" &amp; '
+  '\'single\' values&gt;';
+
+void _testMode(HtmlEscape escape, String input, String expected) {
+  _testConvert(escape, input, expected);
+  _testTransform(escape, input, expected);
+  _testChunked(escape, input, expected);
+}
+
+void _testChunked(HtmlEscape escape, String input, String expected) {
+  var buffer = new StringBuffer();
+
+  var rootSink = new StringConversionSink.fromStringSink(buffer);
+  var sink = escape.startChunkedConversion(rootSink);
+
+  sink.addSlice("1" + input + "2", 1, input.length + 1, false);
+  sink.close();
+
+  Expect.equals(expected, buffer.toString());
+}
+
+void _testConvert(HtmlEscape escape, String input, String expected) {
+  var output = escape.convert(input);
+  Expect.equals(expected, output);
+}
+
+void _testTransform(HtmlEscape escape, String input, String expected) {
+  var controller = new StreamController(sync: true);
+
+  var stream = controller.stream
+      .transform(escape);
+
+  var done = false;
+  int count = 0;
+
+  void stringData(value) {
+    Expect.equals(expected, value);
+    count++;
+  }
+
+  void streamClosed() {
+    done = true;
+  }
+
+  stream.listen(
+      stringData,
+      onDone: streamClosed);
+
+
+  for(var i = 0; i < _COUNT; i++) {
+    controller.add(input);
+  }
+  controller.close();
+  Expect.isTrue(done);
+  Expect.equals(_COUNT, count);
+}
+
+const _COUNT = 3;
+
+void main() {
+  _testMode(HTML_ESCAPE, _TEST_INPUT, _OUTPUT_UNKNOWN);
+  _testMode(const HtmlEscape(), _TEST_INPUT, _OUTPUT_UNKNOWN);
+  _testMode(const HtmlEscape(HtmlEscapeMode.UNKNOWN), _TEST_INPUT, _OUTPUT_UNKNOWN);
+  _testMode(const HtmlEscape(HtmlEscapeMode.ATTRIBUTE), _TEST_INPUT, _OUTPUT_ATTRIBUTE);
+  _testMode(const HtmlEscape(HtmlEscapeMode.ELEMENT), _TEST_INPUT, _OUTPUT_ELEMENT);
+  _testMode(HTML_ESCAPE, _NOOP, _NOOP);
+}