sdk/lib/_internal/compiler/implementation/lib/mirrors.dart

// Copyright (c) 2012, 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.

library dart_mirrors;

import 'dart:isolate';

part '../../../../mirrors/mirrors.dart';

/**
 * Stub class for the mirror system.
 */
class _Mirrors {
  static MirrorSystem currentMirrorSystem() {
    _ensureEnabled();
    throw new UnsupportedError("MirrorSystem not implemented");
  }

  static Future<MirrorSystem> mirrorSystemOf(SendPort port) {
    _ensureEnabled();
    throw new UnsupportedError("MirrorSystem not implemented");
  }

  static InstanceMirror reflect(Object reflectee) {
    _ensureEnabled();
    return new _InstanceMirror(reflectee);
  }
}

class _InstanceMirror extends InstanceMirror {
  static final Expando<ClassMirror> classMirrors = new Expando<ClassMirror>();

  final reflectee;

  _InstanceMirror(this.reflectee) {
    _ensureEnabled();
  }

  bool get hasReflectee => true;

  ClassMirror get type {
    String className = Primitives.objectTypeName(reflectee);
    var constructor = Primitives.getConstructor(className);
    var mirror = classMirrors[constructor];
    if (mirror == null) {
      mirror = new _ClassMirror(className, constructor);
      classMirrors[constructor] = mirror;
    }
    return mirror;
  }

  Future<InstanceMirror> invoke(String memberName,
                                List<Object> positionalArguments,
                                [Map<String,Object> namedArguments]) {
    if (namedArguments != null && !namedArguments.isEmpty) {
      throw new UnsupportedError('Named arguments are not implemented');
    }
    // Copy the list to ensure that it can safely be passed to
    // JavaScript.
    var jsList = new List.from(positionalArguments);
    var mangledName = '${memberName}\$${positionalArguments.length}';
    var method = JS('var', '#[#]', reflectee, mangledName);
    var completer = new Completer<InstanceMirror>();
    // TODO(ahe): [Completer] or [Future] should have API to create a
    // delayed action.  Simulating with a [Timer].
    new Timer(0, (timer) {
      if (JS('String', 'typeof #', method) == 'function') {
        var result =
            JS('var', '#.apply(#, #)', method, reflectee, jsList);
        completer.complete(new _InstanceMirror(result));
      } else {
        completer.completeException('not a method $memberName');
      }
    });
    return completer.future;
  }

  String toString() => 'InstanceMirror($reflectee)';
}

class _ClassMirror extends ClassMirror {
  final String _name;
  final _jsConstructor;

  _ClassMirror(this._name, this._jsConstructor) {
    _ensureEnabled();
  }

  String toString() => 'ClassMirror($_name)';
}

_ensureEnabled() {
  if (Primitives.mirrorsEnabled) return;
  throw new UnsupportedError('dart:mirrors is an experimental feature');
}