Mojo JS Bindings: Eliminate foo$ Stub and Proxy class members

mojo/public/js/bindings.js

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+define("mojo/public/js/bindings", [
+  "mojo/public/js/router",
+], function(router) {
+
+  var Router = router.Router;
+
+  var kProxyProperties = Symbol("proxyProperties");
+  var kStubProperties = Symbol("stubProperties");
+
+  // Public proxy class properties that are managed at runtime by the JS
+  // bindings. See ProxyBindings below.
+  function ProxyProperties(receiver) {
+    this.receiver = receiver;
+  }
+
+  ProxyProperties.prototype.getLocalDelegate = function() {
+    return this.local && StubBindings(this.local).delegate;
+  }
+
+  ProxyProperties.prototype.setLocalDelegate = function(impl) {
+    if (this.local)
+      StubBindings(this.local).delegate = impl;
+    else
+      throw new Error("no stub object");
+  }
+
+  // Public stub class properties that are managed at runtime by the JS
+  // bindings. See StubBindings below.
+  function StubProperties(delegate) {
+    this.delegate = delegate;
+  }
+
+  // The base class for generated proxy classes.
+  function ProxyBase(receiver) {
+    this[kProxyProperties] = new ProxyProperties(receiver);
+
+    // TODO(hansmuller): Temporary, for Chrome backwards compatibility.
+    if (receiver instanceof Router)
+      this.receiver_ = receiver;
+  }
+
+  // The base class for generated stub classes.
+  function StubBase(delegate) {
+    this[kStubProperties] = new StubProperties(delegate);
+  }
+
+  // Provides access to properties added to a proxy object without risking
+  // Mojo interface name collisions. Unless otherwise specified, the initial
+  // value of all properties is undefined.
+  //
+  // ProxyBindings(proxy).connection - The Connection object that links the
+  //   proxy for a remote Mojo service to an optional local stub for a local
+  //   service. The value of ProxyBindings(proxy).connection.remote == proxy.
+  //
+  // ProxyBindings(proxy).local  - The "local" stub object whose delegate
+  //   implements the proxy's Mojo client interface.
+  //
+  // ProxyBindings(proxy).setLocalDelegate(impl) - Sets the implementation
+  //   delegate of the proxy's client stub object. This is just shorthand
+  //   for |StubBindings(ProxyBindings(proxy).local).delegate = impl|.
+  //
+  // ProxyBindings(proxy).getLocalDelegate() - Returns the implementation
+  //   delegate of the proxy's client stub object. This is just shorthand
+  //   for |StubBindings(ProxyBindings(proxy).local).delegate|.
+
+  function ProxyBindings(proxy) {
+    return (proxy instanceof ProxyBase) ? proxy[kProxyProperties] : proxy;
+  }
+
+  // Provides access to properties added to a stub object without risking
+  // Mojo interface name collisions. Unless otherwise specified, the initial
+  // value of all properties is undefined.
+  //
+  // StubBindings(stub).delegate - The optional implementation delegate for
+  //  the Mojo interface stub.
+  //
+  // StubBindings(stub).connection - The Connection object that links an
+  //   optional proxy for a remote service to this stub. The value of
+  //   StubBindings(stub).connection.local == stub.
+  //
+  // StubBindings(stub).remote - A proxy for the the stub's Mojo client
+  //   service.
+
+  function StubBindings(stub) {
+    return stub instanceof StubBase ?  stub[kStubProperties] : stub;
+  }
+
+  var exports = {};
+  exports.EmptyProxy = ProxyBase;
+  exports.EmptyStub = StubBase;
+  exports.ProxyBase = ProxyBase;
+  exports.ProxyBindings = ProxyBindings;
+  exports.StubBase = StubBase;
+  exports.StubBindings = StubBindings;
+  return exports;
+});