third_party/WebKit/LayoutTests/editing/inserting/before-after-input-element.html

<script>
if (window.testRunner)
    testRunner.dumpEditingCallbacks();
</script>
<p>This tests text insertion before/after an input element.</p>
<div id="div" contenteditable="true"><input type="text"></div>

<script>
var div = document.getElementById("div");
var sel = window.getSelection();
sel.collapse(div, 0);

document.execCommand("InsertText", false, "Hello");
sel.collapse(div, div.childNodes.length);

document.execCommand("InsertText", false, "World");
</script>