Merge pull request web-platform-tests#132 from w3c/jgraham/message_ev…

…ents

Add ability to subscribe to only certain events via postMessage.

testharness.js

@@ -22,7 +22,8 @@ policies and contribution forms [3].
             "normal":10000,
             "long":60000
         },
-        test_timeout:null
+        test_timeout:null,
+        message_events: ["start", "test_state", "result", "completion"]
     };
 
     var xhtml_ns = "http://www.w3.org/1999/xhtml";
@@ -64,6 +65,40 @@ policies and contribution forms [3].
         this.output_handler = null;
         this.all_loaded = false;
         var this_obj = this;
+        this.message_events = [];
+
+        this.message_functions = {
+            start: [add_start_callback, remove_start_callback,
+                    function (properties) {
+                        this_obj._dispatch("start_callback", [properties],
+                                           {type: "start", properties: properties});
+                    }],
+
+            test_state: [add_test_state_callback, remove_test_state_callback,
+                         function(test) {
+                             this_obj._dispatch("test_state_callback", [test],
+                                                {type: "test_state",
+                                                 test: test.structured_clone()});
+                         }],
+            result: [add_result_callback, remove_result_callback,
+                     function (test) {
+                         this_obj.output_handler.show_status();
+                         this_obj._dispatch("result_callback", [test],
+                                            {type: "result",
+                                             test: test.structured_clone()});
+                     }],
+            completion: [add_completion_callback, remove_completion_callback,
+                         function (tests, harness_status) {
+                             var cloned_tests = map(tests, function(test) {
+                                 return test.structured_clone();
+                             });
+                             this_obj._dispatch("completion_callback", [tests, harness_status],
+                                                {type: "complete",
+                                                 tests: cloned_tests,
+                                                 status: harness_status.structured_clone()});
+                         }]
+        }
+
         on_event(window, 'load', function() {
             this_obj.all_loaded = true;
         });
@@ -150,30 +185,39 @@ policies and contribution forms [3].
         this.output_handler = output;
 
         var this_obj = this;
+
         add_start_callback(function (properties) {
             this_obj.output_handler.init(properties);
-            this_obj._dispatch("start_callback", [properties],
-                           { type: "start", properties: properties });
         });
+
         add_test_state_callback(function(test) {
             this_obj.output_handler.show_status();
-            this_obj._dispatch("test_state_callback", [test],
-                               { type: "test_state", test: test.structured_clone() });
         });
+
         add_result_callback(function (test) {
             this_obj.output_handler.show_status();
-            this_obj._dispatch("result_callback", [test],
-                               { type: "result", test: test.structured_clone() });
         });
+
         add_completion_callback(function (tests, harness_status) {
             this_obj.output_handler.show_results(tests, harness_status);
-            var cloned_tests = map(tests, function(test) { return test.structured_clone(); });
-            this_obj._dispatch("completion_callback", [tests, harness_status],
-                               { type: "complete", tests: cloned_tests,
-                                 status: harness_status.structured_clone() });
         });
+        this.setup_messages(settings.message_events);
     };
 
+    WindowTestEnvironment.prototype.setup_messages = function(new_events) {
+        var this_obj = this;
+        forEach(settings.message_events, function(x) {
+            var current_dispatch = this_obj.message_events.indexOf(x) !== -1;
+            var new_dispatch = new_events.indexOf(x) !== -1;
+            if (!current_dispatch && new_dispatch) {
+                this_obj.message_functions[x][0](this_obj.message_functions[x][2]);
+            } else if (current_dispatch && !new_dispatch) {
+                this_obj.message_functions[x][1](this_obj.message_functions[x][2]);
+            }
+        });
+        this.message_events = new_events;
+    }
+
     WindowTestEnvironment.prototype.next_default_test_name = function() {
         //Don't use document.title to work around an Opera bug in XHTML documents
         var title = document.getElementsByTagName("title")[0];
@@ -185,6 +229,9 @@ policies and contribution forms [3].
 
     WindowTestEnvironment.prototype.on_new_harness_properties = function(properties) {
         this.output_handler.setup(properties);
+        if (properties.hasOwnProperty("message_events")) {
+            this.setup_messages(properties.message_events);
+        }
     };
 
     WindowTestEnvironment.prototype.add_on_loaded_callback = function(callback) {
@@ -1858,21 +1905,42 @@ policies and contribution forms [3].
         tests.test_state_callbacks.push(callback);
     }
 
-    function add_result_callback(callback)
-    {
+    function add_result_callback(callback) {
         tests.test_done_callbacks.push(callback);
     }
 
-    function add_completion_callback(callback)
-    {
-       tests.all_done_callbacks.push(callback);
+    function add_completion_callback(callback) {
+        tests.all_done_callbacks.push(callback);
     }
 
     expose(add_start_callback, 'add_start_callback');
     expose(add_test_state_callback, 'add_test_state_callback');
     expose(add_result_callback, 'add_result_callback');
     expose(add_completion_callback, 'add_completion_callback');
 
+    function remove(array, item) {
+        var index = array.indexOf(item);
+        if (index > -1) {
+            array.splice(index, 1);
+        }
+    }
+
+    function remove_start_callback(callback) {
+        remove(tests.start_callbacks, callback);
+    }
+
+    function remove_test_state_callback(callback) {
+        remove(tests.test_state_callbacks, callback);
+    }
+
+    function remove_result_callback(callback) {
+        remove(tests.test_done_callbacks, callback);
+    }
+
+    function remove_completion_callback(callback) {
+       remove(tests.all_done_callbacks, callback);
+    }
+
     /*
      * Output listener
     */