Implement JsMethodMirror.parameters.

dart/tests/lib/mirrors/parameter_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.
+
+/// Test of [ParameterMirror].
+library test.parameter_test;
+
+@MirrorsUsed(targets: 'test.parameter_test', override: '*')
+import 'dart:mirrors';
+
+import 'stringify.dart';
+
+class B {
+  B();
+  B.foo(int x);
+  B.bar(int z, x);
+}
+
+main() {
+  var constructors = reflectClass(B).constructors;
+
+  expect('{B: Method(s(B) in s(B), constructor), '
+         'B.bar: Method(s(B.bar) in s(B), constructor), '
+         'B.foo: Method(s(B.foo) in s(B), constructor)}',
+         constructors);
+
+  var unnamedConstructor = constructors[new Symbol('B')];
+
+  expect('[]', unnamedConstructor.parameters);
+  expect('Type(s(B) in s(test.parameter_test), top-level)',
+         unnamedConstructor.returnType);
+
+  var fooConstructor = constructors[new Symbol('B.foo')];
+  expect('[Parameter(s(x) in s(B.foo),'
+         ' type = Type(s(int) in s(dart.core), top-level))]',
+         fooConstructor.parameters);
+  expect('Type(s(B) in s(test.parameter_test), top-level)',
+         fooConstructor.returnType);
+
+  var barConstructor = constructors[new Symbol('B.bar')];
+  expect('[Parameter(s(z) in s(B.bar),'
+         ' type = Type(s(int) in s(dart.core), top-level)), '
+         'Parameter(s(x) in s(B.bar),'
+         ' type = Type(s(dynamic), top-level))]',
+         barConstructor.parameters);
+  expect('Type(s(B) in s(test.parameter_test), top-level)',
+         barConstructor.returnType);
+
+  print(constructors);
+}