Add the 'cache' datatype to the clear-site-data WPT

third_party/WebKit/LayoutTests/external/wpt/clear-site-data/support/test_utils.js

 var TestUtils = (function() {
   function randomString() {
     var result = "";
     for (var i = 0; i < 5; i++)
         result += String.fromCharCode(97 + Math.floor(Math.random() * 26));
     return result;
   };
 
+  /** @string The base URL this test. */
+  var base_url = location.origin + "/clear-site-data/";
+
+  /** @string Name of the resource to be tested for cache emptiness. */
+  var cached_resource_name;
+
   /**
    * Representation of one datatype.
    * @typedef Datatype
    * @type{object}
    * @property{string} name Name of the datatype.
    * @method{function():Void} add A function to add an instance of the datatype.
    * @method{function():boolean} isEmpty A function that tests whether
    *     the datatype's storage backend is empty.
    */
   var Datatype;
 
   var TestUtils = {};
 
   /**
+   * Sets the name of the resource used to test cache emptiness.
+   * @param{string} name Name of the resource.
+   */
+  TestUtils.setCachedResourceName = function(name) {
+    cached_resource_name = name;
+  };
+
+  /** Randomly changes the name of the resource used to test cache emptiness. */
+  TestUtils.bustCache = function() {
+    TestUtils.setCachedResourceName(randomString());
+  };
+
+  /**
    * All datatypes supported by Clear-Site-Data.
    * @param{Array.<Datatype>}
    */
   TestUtils.DATATYPES = [
     {
       "name": "cookies",
       "add": function() {
         return new Promise(function(resolve, reject) {
           document.cookie = randomString() + "=" + randomString();
           resolve();
@@ skipping 11 matching lines @@
         return new Promise(function(resolve, reject) {
           localStorage.setItem(randomString(), randomString());
           resolve();
         });
       },
       "isEmpty": function() {
         return new Promise(function(resolve, reject) {
           resolve(!localStorage.length);
         });
       }
-    }
+    },
+    {
+      "name": "cache",
+      "add": function() {
+        // Request a resource from the get_resource_to_cache.py server.
+        // The server is instructed to return a high "Cache-Control: max-age"
+        // header value, to ensure that this resource will really be added
+        // to the cache.
+        return fetch(base_url + "support/get-resource-to-cache.py?" +
+                         cached_resource_name);
+      },
+      "isEmpty": function() {
+        return new Promise(function(resolve, reject) {
+          // Request the resource with the "Cache-Control: only-if-cached"
+          // header. If the request suceeds, the resource must have been found
+          // in the cache. Since not all user agents support this header value,
+          // the get-resource-to-cache.py server is instructed to respond with
+          // status code 500 if it sees such a request.
+          var fetch_options = {
+            "headers": new Headers({ "Cache-Control": "only-if-cached" }),
+          };
+
+          fetch(base_url + "support/get-resource-to-cache.py?" +
+                    cached_resource_name,
+                fetch_options)
+              .then(function(response) {
+                resolve(response.status == 500  /* Internal server error. */);
+              }).catch(function() {
+                resolve(true);
+              });
+        });
+      }
+    },
   ];
 
   /**
    * All possible combinations of datatypes.
    * @property {Array.<Array.<Datatype>>}
    */
   TestUtils.COMBINATIONS = (function() {
     var combinations = [];
     for (var mask = 0; mask < (1 << TestUtils.DATATYPES.length); mask++) {
       var combination = [];
@@ skipping 10 matching lines @@
   })();
 
   /**
    * Get the support server URL that returns a Clear-Site-Data header
    * to clear |datatypes|.
    * @param{Array.<Datatype>} datatypes The list of datatypes to be deleted.
    * @return string The URL to be queried.
    */
   TestUtils.getClearSiteDataUrl = function(datatypes) {
     names = datatypes.map(function(e) { return e.name });
-    return "support/echo-clear-site-data.py?" + names.join("&");
+    return base_url + "support/echo-clear-site-data.py?cached_resource_name=" +
+        cached_resource_name + "&" + names.join("&");
   }
 
   return TestUtils;
 })();