Bug 494749 - mochitest-browser-chrome: browser_490040.js times out intermittently, refactoring of the test, r=dietrich

browser/components/sessionstore/test/browser/browser_490040.js

@@ -38,51 +38,69 @@
 function test() {
   /** Test for Bug 490040 **/
 
-  let ss = Cc["@mozilla.org/browser/sessionstore;1"].getService(Ci.nsISessionStore);
-  let os = Cc["@mozilla.org/observer-service;1"].getService(Ci.nsIObserverService);
+  let ss = Cc["@mozilla.org/browser/sessionstore;1"].
+           getService(Ci.nsISessionStore);
+  let os = Cc["@mozilla.org/observer-service;1"].
+           getService(Ci.nsIObserverService);
+  let ww = Cc["@mozilla.org/embedcomp/window-watcher;1"].
+           getService(Ci.nsIWindowWatcher);
 
   waitForExplicitFinish();
 
-  function testWithState(aState, aCallback) {
-    // ensure we can store the window if need be
+  function testWithState(aState) {
+    // Ensure we can store the window if needed.
     let curClosedWindowCount = ss.getClosedWindowCount();
-    gPrefService.setIntPref("browser.sessionstore.max_windows_undo", curClosedWindowCount + 1);
+    gPrefService.setIntPref("browser.sessionstore.max_windows_undo",
+                            curClosedWindowCount + 1);
 
-    let theWin = openDialog(location, "_blank", "chrome,all,dialog=no");
-    theWin.addEventListener("load", function(aEvent) {
-      theWin.removeEventListener("load", arguments.callee, true);
+    let windowObserver = {
+      observe: function(aSubject, aTopic, aData) {
+        let theWin = aSubject.QueryInterface(Ci.nsIDOMWindow);
 
-      ss.setWindowState(theWin, JSON.stringify(aState.windowState), true);
+        switch(aTopic) {
+          case "domwindowopened":
+            theWin.addEventListener("load", function () {
+              theWin.removeEventListener("load", arguments.callee, false);
+              executeSoon(function() {
+                // Close the window as soon as the first tab loads, or
+                // immediately if there are no tabs.
+                if (aState.windowState.windows[0].tabs[0].entries.length) {
+                  theWin.gBrowser.addEventListener("load", function() {
+                    theWin.gBrowser.removeEventListener("load",
+                                                        arguments.callee, true);
+                    theWin.close();
+                  }, true);
+                } else {
+                  executeSoon(function() {
+                    theWin.close();
+                  });
+                }
+                ss.setWindowState(theWin, JSON.stringify(aState.windowState),
+                                  true);
+              });
+            }, false);
+            break;
 
-      let observer = {
-        QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver,
-                                               Ci.nsISupportsWeakReference]),
-        observe: function(aSubject, aTopic, aData) {
-          let _this = this;
-          // use executeSoon to ensure this happens after SS observer
-          executeSoon(function() {
-            is(ss.getClosedWindowCount(), curClosedWindowCount + (aState.shouldBeAdded ? 1 : 0),
-               "That window should " + (aState.shouldBeAdded ? "" : "not ") + "be restorable");
-            os.removeObserver(_this, "domwindowclosed");
-            executeSoon(aCallback);
-          });
+          case "domwindowclosed":
+            ww.unregisterNotification(this);
+            // Use executeSoon to ensure this happens after SS observer.
+            executeSoon(function() {
+              is(ss.getClosedWindowCount(),
+                 curClosedWindowCount + (aState.shouldBeAdded ? 1 : 0),
+                 "That window should " + (aState.shouldBeAdded ? "" : "not ") +
+                 "be restorable");
+              executeSoon(runNextTest);
+            });
+            break;
         }
-      };
-      os.addObserver(observer, "domwindowclosed", true);
-
-      // Close the window as soon as the first tab loads, or immediately if
-      // there are no tabs.
-      if (aState.windowState.windows[0].tabs[0].entries.length) {
-        theWin.gBrowser.addEventListener("load", function() {
-          theWin.gBrowser.removeEventListener("load", arguments.callee, true);
-          theWin.close();
-        }, true);
-      } else {
-        executeSoon(function() {
-          theWin.close();
-        });
       }
-    }, true);
+    }
+    ww.registerNotification(windowObserver);
+    ww.openWindow(null,
+                  location,
+                  "_blank",
+                  "chrome,all,dialog=no",
+                  null);
   }
 
   // Only windows with open tabs are restorable. Windows where a lone tab is
@@ -128,15 +146,16 @@ function test() {
     }
   ];
 
-  testWithState(states[0], function() {
-    testWithState(states[1], function() {
-      testWithState(states[2], function() {
-        testWithState(states[3], function() {
-          gPrefService.clearUserPref("browser.sessionstore.max_windows_undo");
-          finish();
-        });
-      });
-    });
-  });
+  function runNextTest() {
+    if (states.length) {
+      let state = states.shift();
+      testWithState(state);
+    }
+    else {
+      gPrefService.clearUserPref("browser.sessionstore.max_windows_undo");
+      finish();
+    }
+  }
+  runNextTest();
 }