auto_tests/tests/Proxy.js

   1 // Copyright (c) 2011 Google, Inc.
   2 //
   3 // Permission is hereby granted, free of charge, to any person obtaining a copy
   4 // of this software and associated documentation files (the "Software"), to deal
   5 // in the Software without restriction, including without limitation the rights
   6 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   7 // copies of the Software, and to permit persons to whom the Software is
   8 // furnished to do so, subject to the following conditions:
   9 //
  10 // The above copyright notice and this permission notice shall be included in
  11 // all copies or substantial portions of the Software.
  12 //
  13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  14 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  15 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  16 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  17 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  18 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  19 // THE SOFTWARE.
  20
  21 /**
  22  * @fileoverview A general purpose object proxy that logs all method calls.
  23  *
  24  * @author konigsberg@google.com (Robert Konigsberg)
  25  */
  26
  27 var Proxy = function(delegate) {
  28   this.delegate__ = delegate;
  29   this.calls__ = [];
  30   this.propertiesToTrack__ = [];
  31
  32   for (var propname in delegate) {
  33     var type = typeof(delegate[propname]);
  34
  35     // Functions are passed through to the delegate, and are logged
  36     // prior to the call.
  37     if (type == "function") {
  38       function makeFunc(name) {
  39         return function() {
  40           this.log__(name, arguments);
  41           this.delegate__[name].apply(this.delegate__, arguments);
  42         }
  43       };
  44       this[propname] = makeFunc(propname);
  45     } else if (type == "string" || type == "number") {
  46       // String and number properties are just passed through to the delegate.
  47       this.propertiesToTrack__.push(propname);
  48       function makeSetter(name) {
  49         return function(x) {
  50           this.delegate__[name] = x;
  51         }
  52       };
  53       this.__defineSetter__(propname, makeSetter(propname));
  54
  55       function makeGetter(name) {
  56         return function() {
  57           return this.delegate__[name];
  58         }
  59       };
  60       this.__defineGetter__(propname, makeGetter(propname));
  61     }
  62   }
  63 };
  64
  65 Proxy.prototype.log__ = function(name, args) {
  66   var properties = {};
  67   for (var propIdx in this.propertiesToTrack__) {
  68     var prop = this.propertiesToTrack__[propIdx];
  69     properties[prop] = this.delegate__[prop];
  70   }
  71   var call = { name : name, args : args, properties: properties };
  72   this.calls__.push(call);
  73 };
  74