| <!DOCTYPE html> |
| <html> |
| |
| <body> |
| <input id="field" onbeforeinput=handleBeforeInput(event)></input> |
| <script src="../../resources/dump-as-markup.js"></script> |
| <script> |
| Markup.description(`To manually test this, type some into the input field below and try to undo. The value of the text field should not change after attempting to undo.`); |
| |
| (function() { |
| if (!window.internals || !window.eventSender || !window.testRunner) |
| return; |
| |
| document.querySelector("#field").focus(); |
| |
| eventSender.keyDown("a", []); |
| eventSender.keyDown("b", []); |
| eventSender.keyDown("c", []); |
| Markup.dump("field", "initial value"); |
| |
| testRunner.execCommand("Undo"); |
| Markup.dump("field", "after prevented undo"); |
| })(); |
| |
| function handleBeforeInput(event) |
| { |
| if (event.inputType === "historyUndo") |
| event.preventDefault(); |
| } |
| </script> |
| </body> |
| |
| </html> |
