1 files changed, 80 insertions, 0 deletions
diff --git a/browser/components/sessionstore/test/browser_477657.js b/browser/components/sessionstore/test/browser_477657.js
new file mode 100644
index 0000000000..f54c270bf5
--- /dev/null
+++ b/browser/components/sessionstore/test/browser_477657.js
@@ -0,0 +1,80 @@
+/* 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/. */
+
+add_task(async function test_sizemodeDefaults() {
+  /** Test for Bug 477657 **/
+  let newWin = openDialog(location, "_blank", "chrome,all,dialog=no");
+  await promiseWindowLoaded(newWin);
+  let newState = {
+    windows: [
+      {
+        tabs: [{ entries: [] }],
+        _closedTabs: [
+          {
+            state: { entries: [{ url: "about:" }] },
+            title: "About:",
+          },
+        ],
+        sizemode: "maximized",
+      },
+    ],
+  };
+
+  let uniqueKey = "bug 477657";
+  let uniqueValue = "unik" + Date.now();
+
+  ss.setCustomWindowValue(newWin, uniqueKey, uniqueValue);
+  is(
+    ss.getCustomWindowValue(newWin, uniqueKey),
+    uniqueValue,
+    "window value was set before the window was overwritten"
+  );
+
+  await setWindowState(newWin, newState, true);
+  // use newWin.setTimeout(..., 0) to mirror sss_restoreWindowFeatures
+  await new Promise(resolve => newWin.setTimeout(resolve, 0));
+
+  is(
+    ss.getCustomWindowValue(newWin, uniqueKey),
+    "",
+    "window value was implicitly cleared"
+  );
+
+  is(newWin.windowState, newWin.STATE_MAXIMIZED, "the window was maximized");
+
+  is(
+    ss.getClosedTabDataForWindow(newWin).length,
+    1,
+    "the closed tab was added before the window was overwritten"
+  );
+  delete newState.windows[0]._closedTabs;
+  delete newState.windows[0].sizemode;
+
+  await setWindowState(newWin, newState, true);
+  await new Promise(resolve => newWin.setTimeout(resolve, 0));
+
+  is(
+    ss.getClosedTabDataForWindow(newWin).length,
+    0,
+    "closed tabs were implicitly cleared"
+  );
+
+  is(
+    newWin.windowState,
+    newWin.STATE_MAXIMIZED,
+    "the window remains maximized"
+  );
+  newState.windows[0].sizemode = "normal";
+
+  await setWindowState(newWin, newState, true);
+  await new Promise(resolve => newWin.setTimeout(resolve, 0));
+
+  isnot(
+    newWin.windowState,
+    newWin.STATE_MAXIMIZED,
+    "the window was explicitly unmaximized"
+  );
+
+  await BrowserTestUtils.closeWindow(newWin);
+});