Reapply "Port regexp tests from V8 to Dart."

tests/corelib/regexp/non-bmp_test.dart

+// Copyright (c) 2014, the Dart project authors. All rights reserved.
+// Copyright 2013 the V8 project authors. All rights reserved.
+// Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1.  Redistributions of source code must retain the above copyright
+//     notice, this list of conditions and the following disclaimer.
+// 2.  Redistributions in binary form must reproduce the above copyright
+//     notice, this list of conditions and the following disclaimer in the
+//     documentation and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+// ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import 'v8_regexp_utils.dart';
+import 'package:expect/expect.dart';
+
+void main() {
+  description(
+  'Tests that regular expressions treat non-BMP characters as two separate characters. '
+  + 'From a Unicode correctness point of view this is wrong, but it is what other browsers do. '
+  + 'And given that we store strings as UTF-16, it is also more efficient to implement. '
+  + 'Also test some other cases related to UTF-8 and UTF-16.'
+  );
+
+  var surrogatePair = new String.fromCharCode(0xD800) + new String.fromCharCode(0xDC00);
+
+  assertEquals(new RegExp(r".").firstMatch(surrogatePair).group(0).length, 1);
+  assertEquals(new RegExp(r"\D").firstMatch(surrogatePair).group(0).length, 1);
+  assertEquals(new RegExp(r"\S").firstMatch(surrogatePair).group(0).length, 1);
+  assertEquals(new RegExp(r"\W").firstMatch(surrogatePair).group(0).length, 1);
+  assertEquals(new RegExp(r"[^x]").firstMatch(surrogatePair).group(0).length, 1);
+
+  assertEquals(new RegExp(r".{1,2}").firstMatch("!!" + new String.fromCharCode(0xA1)).group(0).length, 2);
+  shouldBeNull(new RegExp(r".").firstMatch(""));
+}