Rewrite, document, and test qualifiedNamesIn.

dart/tests/try/poi/qualified_names_test.dart

+// Copyright (c) 2014, 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.
+
+// Test of [qualifiedNamesIn] and [canNamesResolveTo].
+library trydart.qualified_names_test;
+
+import 'package:dart2js_incremental/library_updater.dart' show
+    canNamesResolveTo,
+    qualifiedNamesIn;
+
+import 'compiler_test_case.dart';
+
+typedef Checker(LibraryElement script);
+
+class NameTestCase extends CompilerTestCase {
+  final Checker check;
+
+  NameTestCase(String source, this.check)
+      : super(source);
+
+  Future run() => mainApp.then(check);
+}
+
+main() {
+  runTests(tests.map((l) => new NameTestCase(l.first, l.last)).toList());
+}
+
+final List tests = [
+    ["main() { x; }",
+     (LibraryElement script) {
+       var names = qualifiedNamesIn(script.findLocal("main"));
+       Expect.setEquals(["main", "x"].toSet(), names);
+     }],
+
+    ["main() { x; x.y; }",
+     (LibraryElement script) {
+       var names = qualifiedNamesIn(script.findLocal("main"));
+       Expect.setEquals(["main", "x", "x.y"].toSet(), names);
+     }],
+
+    ["main() { x; x.y; x.y.z; x.y.z.w;}",
+     (LibraryElement script) {
+       var names = qualifiedNamesIn(script.findLocal("main"));
+       // ".w" is skipped.
+       Expect.setEquals(["main", "x", "x.y", "x.y.z"].toSet(), names);
+     }],
+
+
+    ["x() {} y() {} z() {} w() {} main() { x; x.y; x.y.z; x.y.z.w;}",
+     (LibraryElement script) {
+       var main = script.findLocal("main");
+       var names = qualifiedNamesIn(main);
+       var x = script.findLocal("x");
+       var y = script.findLocal("y");
+       var z = script.findLocal("z");
+       var w = script.findLocal("w");
+       Expect.isTrue(canNamesResolveTo(names, main, script));
+       Expect.isTrue(canNamesResolveTo(names, x, script));
+       Expect.isFalse(canNamesResolveTo(names, y, script));
+       Expect.isFalse(canNamesResolveTo(names, z, script));
+       Expect.isFalse(canNamesResolveTo(names, w, script));
+     }],
+];