Add more extensive type annotations so we get improved type checking.

src/ascender/ascender_script.js

@@ -10,6 +10,7 @@ goog.provide('webfont.AscenderScript');
  * });
  *
  * @constructor
+ * @implements {webfont.FontModule}
  */
 webfont.AscenderScript = function(domHelper, configuration) {
   this.domHelper_ = domHelper;

src/core/font.js

@@ -27,10 +27,17 @@ goog.scope(function () {
       FontWatcher = webfont.FontWatcher,
       Size = webfont.Size;
 
+  /**
+   * @param {string} name
+   * @param {webfont.FontModuleFactory} factory
+   */
   WebFont.prototype.addModule = function(name, factory) {
     this.fontModuleLoader_.addModuleFactory(name, factory);
   };
 
+  /**
+   * @param {Object} configuration
+   */
   WebFont.prototype.load = function(configuration) {
     var context = configuration['context'] || this.mainWindow_;
     this.domHelper_ = new DomHelper(this.mainWindow_, context);
@@ -45,10 +52,18 @@ goog.scope(function () {
     }
   };
 
+  /**
+   * @param {webfont.FontModule} module
+   * @param {webfont.EventDispatcher} eventDispatcher
+   * @param {webfont.FontWatcher} fontWatcher
+   * @param {boolean} support
+   */
   WebFont.prototype.isModuleSupportingUserAgent_ = function(module, eventDispatcher,
       fontWatcher, support) {
     var fontWatchRunnerCtor = module.getFontWatchRunnerCtor ?
-        module.getFontWatchRunnerCtor() : webfont.FontWatchRunner;
+        module.getFontWatchRunnerCtor() : webfont.FontWatchRunner,
+        that = this;
+
     if (!support) {
       var allModulesLoaded = --this.moduleLoading_ == 0;
 
@@ -63,21 +78,46 @@ goog.scope(function () {
       fontWatcher.watch([], {}, {}, fontWatchRunnerCtor, allModulesLoaded);
       return;
     }
-    module.load(goog.bind(this.onModuleReady_, this, eventDispatcher,
-        fontWatcher, fontWatchRunnerCtor));
+
+    module.load(function (fontFamilies, fontVariations) {
+      that.onModuleReady_(eventDispatcher, fontWatcher, fontWatchRunnerCtor, fontFamilies, fontVariations);
+    });
   };
 
+  /**
+   * @param {webfont.EventDispatcher} eventDispatcher
+   * @param {webfont.FontWatcher} fontWatcher
+   * @param {function(new:webfont.FontWatchRunner,
+   *                  function(string, string),
+   *                  function(string, string),
+   *                  webfont.DomHelper,
+   *                  string,
+   *                  string,
+   *                  webfont.BrowserInfo,
+   *                  number=,
+   *                  Object.<string, boolean>=,
+   *                  string=)} fontWatchRunnerCtor
+   * @param {webfont.FontFamilies} fontFamilies
+   * @param {webfont.FontVariations=} opt_fontVariations
+   * @param {webfont.FontTestStrings=} opt_fontTestStrings
+   */
   WebFont.prototype.onModuleReady_ = function(eventDispatcher, fontWatcher,
-      fontWatchRunnerCtor, fontFamilies, opt_fontDescriptions, opt_fontTestStrings) {
+      fontWatchRunnerCtor, fontFamilies, opt_fontVariations, opt_fontTestStrings) {
     var allModulesLoaded = --this.moduleLoading_ == 0;
 
     if (allModulesLoaded) {
       eventDispatcher.dispatchLoading();
     }
 
-    setTimeout(goog.bind(fontWatcher.watch, fontWatcher, fontFamilies, opt_fontDescriptions || {}, opt_fontTestStrings || {}, fontWatchRunnerCtor, allModulesLoaded), 0);
+    setTimeout(function () {
+      fontWatcher.watch(fontFamilies, opt_fontVariations || {}, opt_fontTestStrings || {}, fontWatchRunnerCtor, allModulesLoaded);
+    }, 0);
   };
 
+  /**
+   * @param {webfont.EventDispatcher} eventDispatcher
+   * @param {Object} configuration
+   */
   WebFont.prototype.load_ = function(eventDispatcher, configuration) {
     var modules = this.fontModuleLoader_.getModules(configuration, this.domHelper_),
         timeout = configuration['timeout'],

src/core/fontmoduleloader.js

@@ -1,19 +1,56 @@
 goog.provide('webfont.FontModuleLoader');
+goog.provide('webfont.FontModule');
+goog.provide('webfont.FontModuleFactory');
+
+/**
+ * @interface
+ */
+webfont.FontModule = function () {};
+
+goog.scope(function () {
+  var FontModule = webfont.FontModule;
+
+  /**
+   * @param {webfont.UserAgent} userAgent
+   * @param {function(boolean)} support
+   */
+  FontModule.prototype.supportUserAgent = function (userAgent, support) {};
+
+  /**
+   * @param {function(webfont.FontFamilies, webfont.FontVariations=, webfont.FontTestStrings=)} onReady
+   */
+  FontModule.prototype.load = function (onReady) {};
+});
+
+/** @typedef {function(Object, webfont.DomHelper): webfont.FontModule} */
+webfont.FontModuleFactory;
 
 /**
  * @constructor
  */
 webfont.FontModuleLoader = function() {
+  /**
+   * @type {Object.<string, webfont.FontModuleFactory>}
+   */
   this.modules_ = {};
 };
 
 goog.scope(function () {
   var FontModuleLoader = webfont.FontModuleLoader;
 
+  /**
+   * @param {string} name
+   * @param {webfont.FontModuleFactory} factory
+   */
   FontModuleLoader.prototype.addModuleFactory = function(name, factory) {
     this.modules_[name] = factory;
   };
 
+  /**
+   * @param {Object} configuration
+   * @param {webfont.DomHelper} domHelper
+   * @return {Array.<webfont.FontModule>}
+   */
   FontModuleLoader.prototype.getModules = function(configuration, domHelper) {
     var modules = [];
 

src/core/fontwatcher.js

@@ -36,9 +36,16 @@ goog.scope(function () {
    *     of each family to watch. Described with FVD.
    * @param {Object.<string, string>} fontTestStrings The font test strings for
    *     each family.
-   * @param {function(new:webfont.FontWatchRunner, function(string, string),
-   *     function(string, string), webfont.DomHelper,
-   *     string, string, webfont.BrowserInfo, number=, Object.<string, boolean>=, string=)} fontWatchRunnerCtor The font watch runner constructor.
+   * @param {function(new:webfont.FontWatchRunner,
+   *                  function(string, string),
+   *                  function(string, string),
+   *                  webfont.DomHelper,
+   *                  string,
+   *                  string,
+   *                  webfont.BrowserInfo,
+   *                  number=,
+   *                  Object.<string, boolean>=,
+   *                  string=)} fontWatchRunnerCtor The font watch runner constructor.
    * @param {boolean} last True if this is the last set of families to watch.
    */
   FontWatcher.prototype.watch = function(fontFamilies, fontDescriptions,

src/core/initialize.js

@@ -4,6 +4,21 @@ goog.require('webfont.UserAgentParser');
 goog.require('webfont.FontModuleLoader');
 goog.require('webfont.WebFont');
 
+/**
+ * @typedef {Array.<string>}
+ */
+webfont.FontFamilies;
+
+/**
+ * @typedef {Object.<string, Array.<string>>}
+ */
+webfont.FontVariations;
+
+/**
+ * @typedef {Object.<string, Array.<string>>}
+ */
+webfont.FontTestStrings;
+
 // Name of the global object.
 var globalName = 'WebFont';
 

src/custom/customcss.js

@@ -9,6 +9,7 @@ goog.provide('webfont.CustomCss');
  * });
  *
  * @constructor
+ * @implements {webfont.FontModule}
  */
 webfont.CustomCss = function(domHelper, configuration) {
   this.domHelper_ = domHelper;

src/fontdeck/fontdeck_script.js

@@ -4,6 +4,7 @@ goog.require('webfont.FontVariationDescription');
 
 /**
  * @constructor
+ * @implements {webfont.FontModule}
  */
 webfont.FontdeckScript = function(domHelper, configuration) {
   this.domHelper_ = domHelper;

src/google/googlefontapi.js

@@ -7,6 +7,7 @@ goog.require('webfont.LastResortWebKitFontWatchRunner');
 
 /**
  * @constructor
+ * @implements {webfont.FontModule}
  */
 webfont.GoogleFontApi = function(userAgent, domHelper, configuration) {
   this.userAgent_ = userAgent;

src/google/lastresortwebkitfontwatchrunner.js

@@ -75,6 +75,9 @@ goog.scope(function () {
     return webKitLastResortFontSizes;
   };
 
+  /**
+   * @override
+   */
   LastResortWebKitFontWatchRunner.prototype.check_ = function() {
     var sizeA = this.fontRulerA_.getSize();
     var sizeB = this.fontRulerB_.getSize();

src/monotype/monotype_script.js

@@ -10,6 +10,7 @@ projectId: 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'//this is your Fonts.com Web fo
 
 /**
  * @constructor
+ * @implements {webfont.FontModule}
  */
 webfont.MonotypeScript = function (userAgent, domHelper, configuration) {
   this.userAgent_ = userAgent;

src/typekit/typekit_script.js

@@ -2,6 +2,7 @@ goog.provide('webfont.TypekitScript');
 
 /**
  * @constructor
+ * @implements {webfont.FontModule}
  */
 webfont.TypekitScript = function(domHelper, configuration) {
   this.domHelper_ = domHelper;