MD Settings: Adding some unit tests for <settings-main>.

chrome/browser/resources/settings/search_settings.js

Index: chrome/browser/resources/settings/search_settings.js
diff --git a/chrome/browser/resources/settings/search_settings.js b/chrome/browser/resources/settings/search_settings.js
index f001427a140d760bf52ada4df340c8a092609fb8..3d2093e15b498bb269487cbb3a5b62067b27422d 100644
--- a/chrome/browser/resources/settings/search_settings.js
+++ b/chrome/browser/resources/settings/search_settings.js
@@ -100,7 +100,7 @@ cr.define('settings', function() {
    * ensures that <settings-section> instances become visible if any matches
    * occurred under their subtree.
    *
-   * @param {!SearchRequest} request
+   * @param {!settings.SearchRequest} request
    * @param {!Node} root The root of the sub-tree to be searched
    * @private
    */
@@ -167,11 +167,11 @@ cr.define('settings', function() {
   /**
    * @constructor
    *
-   * @param {!SearchRequest} request
+   * @param {!settings.SearchRequest} request
    * @param {!Node} node
    */
   function Task(request, node) {
-    /** @protected {!SearchRequest} */
+    /** @protected {!settings.SearchRequest} */
     this.request = request;
 
     /** @protected {!Node} */
@@ -193,7 +193,7 @@ cr.define('settings', function() {
    * @constructor
    * @extends {Task}
    *
-   * @param {!SearchRequest} request
+   * @param {!settings.SearchRequest} request
    * @param {!Node} node
    */
   function RenderTask(request, node) {
@@ -227,7 +227,7 @@ cr.define('settings', function() {
    * @constructor
    * @extends {Task}
    *
-   * @param {!SearchRequest} request
+   * @param {!settings.SearchRequest} request
    * @param {!Node} node
    */
   function SearchAndHighlightTask(request, node) {
@@ -247,7 +247,7 @@ cr.define('settings', function() {
    * @constructor
    * @extends {Task}
    *
-   * @param {!SearchRequest} request
+   * @param {!settings.SearchRequest} request
    * @param {!Node} page
    */
   function TopLevelSearchTask(request, page) {
@@ -454,11 +454,25 @@ cr.define('settings', function() {
     },
   };
 
+  /** @interface */
+  var SearchManager = function() {};
+
+  SearchManager.prototype = {
+    /**
+     * @param {string} text The text to search for.
+     * @param {!Node} page
+     * @return {!Promise<!settings.SearchRequest>} A signal indicating that
+     *     searching finished.
+     */
+    search: function(text, page) {}
+  };
+
   /**
    * @constructor
+   * @implements {SearchManager}
    */
-  var SearchManager = function() {
-    /** @private {?SearchRequest} */
+  var SearchManagerImpl = function() {
+    /** @private {?settings.SearchRequest} */
     this.activeRequest_ = null;
 
     /** @private {!TaskQueue} */
@@ -469,15 +483,10 @@ cr.define('settings', function() {
       this.activeRequest_ = null;
     }.bind(this));
   };
-  cr.addSingletonGetter(SearchManager);
+  cr.addSingletonGetter(SearchManagerImpl);
 
-  SearchManager.prototype = {
-    /**
-     * @param {string} text The text to search for.
-     * @param {!Node} page
-     * @return {!Promise<!SearchRequest>} A signal indicating that searching
-     *     finished.
-     */
+  SearchManagerImpl.prototype = {
+    /** @override */
     search: function(text, page) {
       // Creating a new request only if the |text| changed.
       if (!this.activeRequest_ || !this.activeRequest_.isSame(text)) {
@@ -499,10 +508,20 @@ cr.define('settings', function() {
 
   /** @return {!SearchManager} */
   function getSearchManager() {
-    return SearchManager.getInstance();
+    return SearchManagerImpl.getInstance();
+  }
+
+  /**
+   * Sets the SearchManager singleton instance, useful for testing.
+   * @param {!SearchManager} searchManager
+   */
+  function setSearchManagerForTesting(searchManager) {
+    SearchManagerImpl.instance_ = searchManager;
   }
 
   return {
     getSearchManager: getSearchManager,
+    setSearchManagerForTesting: setSearchManagerForTesting,
+    SearchRequest: SearchRequest,
   };
 });