1 files changed, 120 insertions, 0 deletions
diff --git a/browser/components/sessionstore/test/browser_491577.js b/browser/components/sessionstore/test/browser_491577.js
new file mode 100644
index 000000000..0e088d702
--- /dev/null
+++ b/browser/components/sessionstore/test/browser_491577.js
@@ -0,0 +1,120 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+function test() {
+  /** Test for Bug 491577 **/
+
+  // test setup
+  waitForExplicitFinish();
+
+  const REMEMBER = Date.now(), FORGET = Math.random();
+  let test_state = {
+    windows: [ { tabs: [{ entries: [{ url: "http://example.com/" }] }], selected: 1 } ],
+    _closedWindows : [
+      // _closedWindows[0]
+      {
+        tabs: [
+          { entries: [{ url: "http://example.com/", title: "title" }] },
+          { entries: [{ url: "http://mozilla.org/", title: "title" }] }
+        ],
+        selected: 2,
+        title: FORGET,
+        _closedTabs: []
+      },
+      // _closedWindows[1]
+      {
+        tabs: [
+         { entries: [{ url: "http://mozilla.org/", title: "title" }] },
+         { entries: [{ url: "http://example.com/", title: "title" }] },
+         { entries: [{ url: "http://mozilla.org/", title: "title" }] },
+        ],
+        selected: 3,
+        title: REMEMBER,
+        _closedTabs: []
+      },
+      // _closedWindows[2]
+      {
+        tabs: [
+          { entries: [{ url: "http://example.com/", title: "title" }] }
+        ],
+        selected: 1,
+        title: FORGET,
+        _closedTabs: [
+          {
+            state: {
+              entries: [
+                { url: "http://mozilla.org/", title: "title" },
+                { url: "http://mozilla.org/again", title: "title" }
+              ]
+            },
+            pos: 1,
+            title: "title"
+          },
+          {
+            state: {
+              entries: [
+                { url: "http://example.com", title: "title" }
+              ]
+            },
+            title: "title"
+          }
+        ]
+      }
+    ]
+  };
+  let remember_count = 1;
+
+  function countByTitle(aClosedWindowList, aTitle) {
+    return aClosedWindowList.filter(aData => aData.title == aTitle).length;
+  }
+
+  function testForError(aFunction) {
+    try {
+      aFunction();
+      return false;
+    }
+    catch (ex) {
+      return ex.name == "NS_ERROR_ILLEGAL_VALUE";
+    }
+  }
+
+  // open a window and add the above closed window list
+  let newWin = openDialog(location, "_blank", "chrome,all,dialog=no");
+  promiseWindowLoaded(newWin).then(() => {
+    gPrefService.setIntPref("browser.sessionstore.max_windows_undo",
+                            test_state._closedWindows.length);
+    ss.setWindowState(newWin, JSON.stringify(test_state), true);
+
+    let closedWindows = JSON.parse(ss.getClosedWindowData());
+    is(closedWindows.length, test_state._closedWindows.length,
+       "Closed window list has the expected length");
+    is(countByTitle(closedWindows, FORGET),
+       test_state._closedWindows.length - remember_count,
+       "The correct amount of windows are to be forgotten");
+    is(countByTitle(closedWindows, REMEMBER), remember_count,
+       "Everything is set up.");
+
+    // all of the following calls with illegal arguments should throw NS_ERROR_ILLEGAL_VALUE
+    ok(testForError(() => ss.forgetClosedWindow(-1)),
+       "Invalid window for forgetClosedWindow throws");
+    ok(testForError(() => ss.forgetClosedWindow(test_state._closedWindows.length + 1)),
+       "Invalid window for forgetClosedWindow throws");
+
+    // Remove third window, then first window
+    ss.forgetClosedWindow(2);
+    ss.forgetClosedWindow(null);
+
+    closedWindows = JSON.parse(ss.getClosedWindowData());
+    is(closedWindows.length, remember_count,
+       "The correct amount of windows were removed");
+    is(countByTitle(closedWindows, FORGET), 0,
+       "All windows specifically forgotten were indeed removed");
+    is(countByTitle(closedWindows, REMEMBER), remember_count,
+       "... and windows not specifically forgetten weren't.");
+
+    // clean up
+    gPrefService.clearUserPref("browser.sessionstore.max_windows_undo");
+    BrowserTestUtils.closeWindow(newWin).then(finish);
+  });
+}