Changes to mirrors in support of metadata access at runtime. Assumes VM changes in flight.…

tests/lib/mirrors/library_metadata_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.
+
+@string @symbol
+library test.library_metadata_test;
+
+import 'dart:mirrors';
+
+const string = 'a metadata string';
+
+const symbol = const Symbol('symbol');
+
+const hest = 'hest';
+
+checkMetadata(DeclarationMirror mirror, List expectedMetadata) {
+  List metadata = mirror.metadata.map((m) => m.reflectee).toList();
+  if (metadata == null) {
+    throw 'Null metadata on $mirror';
+  }
+  int expectedLength = expectedMetadata.length;
+  int actualLength = metadata.length;
+  if (expectedLength != actualLength) {
+    throw 'Expected length = $expectedLength, but got length = $actualLength.';
+  }
+  for (int i = 0; i < expectedLength; i++) {
+    if (metadata[i] != expectedMetadata[i]) {
+      throw '${metadata[i]} is not "${expectedMetadata[i]}"'
+          ' in $mirror at index $i';
+    }
+  }
+  print(metadata);
+}
+
+main() {
+  if (MirrorSystem.getName(symbol) != 'symbol') {
+    // This happened in dart2js due to how early library metadata is
+    // computed.
+    throw 'Bad constant: $symbol';
+  }
+
+  MirrorSystem mirrors = currentMirrorSystem();
+  checkMetadata(mirrors.findLibrary(const Symbol('test.library_metadata_test')).first,
+                [string, symbol]); 
+}