mozilla-release/editor/libeditor/tests/test_bug1258085.html

<!DOCTYPE html>
<title>Test for Bug 1186799</title>
<script src="/tests/SimpleTest/SimpleTest.js"></script>
<script src="/tests/SimpleTest/EventUtils.js"></script>
<link rel="stylesheet" href="/tests/SimpleTest/test.css">
<div contenteditable></div>
<script>
var div = document.querySelector("div");

function reset() {
  div.innerHTML = "x<br> y";
  div.focus();
  synthesizeKey("KEY_ArrowDown");
}

function checks(msg) {
  is(div.innerHTML, "x<br><br>",
     msg + ": Should add a second <br> to prevent collapse of first");
  is(div.childNodes.length, 3, msg + ": No empty text nodes allowed");
  ok(getSelection().isCollapsed, msg + ": Selection must be collapsed");
  is(getSelection().focusNode, div, msg + ": Focus must be in div");
  is(getSelection().focusOffset, 2,
     msg + ": Focus must be between the two <br>s");
}

SimpleTest.waitForExplicitFinish();
SimpleTest.waitForFocus(function() {
  // Put selection after the "y" and backspace
  reset();
  synthesizeKey("KEY_ArrowRight");
  synthesizeKey("KEY_Backspace");
  checks("Collapsed backspace");

  // Now do the same with delete
  reset();
  synthesizeKey("KEY_Delete");
  checks("Collapsed delete");

  // Forward selection
  reset();
  synthesizeKey("KEY_ArrowRight", {shiftKey: true});
  synthesizeKey("KEY_Backspace");
  checks("Forward-selected backspace");

  // Backward selection
  reset();
  synthesizeKey("KEY_ArrowRight");
  synthesizeKey("KEY_ArrowLeft", {shiftKey: true});
  synthesizeKey("KEY_Backspace");
  checks("Backward-selected backspace");

  // Make sure we're not deleting if the whitespace isn't actually collapsed
  div.style.whiteSpace = "pre-wrap";
  reset();
  synthesizeKey("KEY_ArrowRight");
  synthesizeKey("KEY_ArrowRight");
  synthesizeKey("KEY_Backspace");
  is(div.innerHTML, "x<br> ", "pre-wrap: Don't delete uncollapsed space");
  ok(getSelection().isCollapsed, "pre-wrap: Selection must be collapsed");
  is(getSelection().focusNode, div.lastChild,
     "pre-wrap: Focus must be in final text node");
  is(getSelection().focusOffset, 1, "pre-wrap: Focus must be at end of node");

  SimpleTest.finish();
});
</script>