1 files changed, 64 insertions, 0 deletions
diff --git a/editor/libeditor/tests/test_doc_scrollbar_toggled_designMode_on_mousedown.html b/editor/libeditor/tests/test_doc_scrollbar_toggled_designMode_on_mousedown.html
new file mode 100644
index 0000000000..860e87424a
--- /dev/null
+++ b/editor/libeditor/tests/test_doc_scrollbar_toggled_designMode_on_mousedown.html
@@ -0,0 +1,64 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=620906
+-->
+<head>
+  <title>Test for Bug 620906</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=620906">Mozilla Bug 620906</a>
+<p id="display"></p>
+<div id="content">
+  <iframe srcdoc=
+    "<body contenteditable
+          onmousedown='
+            document.designMode=&quot;on&quot;;
+            document.designMode=&quot;off&quot;;
+          '
+    >
+      <div style='height: 1000px;'></div>
+    </body>">
+    </iframe>
+</div>
+<pre id="test">
+<script type="application/javascript">
+
+/** Test for Bug 620906 **/
+SimpleTest.waitForExplicitFinish();
+SimpleTest.waitForFocus(async () => {
+  const iframe = document.querySelector("iframe");
+  is(iframe.contentWindow.scrollY, 0, "Sanity check");
+  const rect = iframe.getBoundingClientRect();
+  const waitForTick = () => {
+    return new Promise(resolve => requestAnimationFrame(
+      () => requestAnimationFrame(resolve))
+    );
+  };
+  await waitForTick();
+  let scrollEventFired = false;
+  iframe.contentWindow.addEventListener("scroll", () => {
+    scrollEventFired = true;
+  }, {once: true});
+  for (let i = 0; i < 10; i++) {
+    synthesizeMouse(iframe, rect.width - 4, rect.height / 2, { type: "mousemove" });
+    synthesizeMouse(iframe, rect.width - 5, rect.height / 2, { type: "mousemove" });
+    synthesizeMouse(iframe, rect.width - 5, rect.height / 2, {});
+    await waitForTick();
+    if (scrollEventFired) {
+      isnot(iframe.contentWindow.scrollY, 0, "The scrollbar should work");
+      SimpleTest.finish();
+      return;
+    }
+  }
+  ok(false, "The scrollbar didn't work");
+  SimpleTest.finish();
+});
+
+</script>
+</pre>
+</body>
+</html>