1 files changed, 37 insertions, 0 deletions
diff --git a/browser/base/content/test/general/browser_bug623893.js b/browser/base/content/test/general/browser_bug623893.js
new file mode 100644
index 000000000..fa6da1b22
--- /dev/null
+++ b/browser/base/content/test/general/browser_bug623893.js
@@ -0,0 +1,37 @@
+add_task(function* test() {
+  yield BrowserTestUtils.withNewTab("data:text/plain;charset=utf-8,1", function* (browser) {
+    BrowserTestUtils.loadURI(browser, "data:text/plain;charset=utf-8,2");
+    yield BrowserTestUtils.browserLoaded(browser);
+
+    BrowserTestUtils.loadURI(browser, "data:text/plain;charset=utf-8,3");
+    yield BrowserTestUtils.browserLoaded(browser);
+
+    yield duplicate(0, "maintained the original index");
+    yield BrowserTestUtils.removeTab(gBrowser.selectedTab);
+
+    yield duplicate(-1, "went back");
+    yield duplicate(1, "went forward");
+    yield BrowserTestUtils.removeTab(gBrowser.selectedTab);
+    yield BrowserTestUtils.removeTab(gBrowser.selectedTab);
+  });
+});
+
+function promiseGetIndex(browser) {
+  return ContentTask.spawn(browser, null, function() {
+    let shistory = docShell.QueryInterface(Ci.nsIInterfaceRequestor)
+                           .getInterface(Ci.nsISHistory);
+    return shistory.index;
+  });
+}
+
+let duplicate = Task.async(function* (delta, msg, cb) {
+  var startIndex = yield promiseGetIndex(gBrowser.selectedBrowser);
+
+  duplicateTabIn(gBrowser.selectedTab, "tab", delta);
+
+  let tab = gBrowser.selectedTab;
+  yield BrowserTestUtils.waitForEvent(tab, "SSTabRestored");
+
+  let endIndex = yield promiseGetIndex(gBrowser.selectedBrowser);
+  is(endIndex, startIndex + delta, msg);
+});