EventTarget:removeEventListener() does not work #66
Description
Hi all,
Fengari seems like an awesome project. I'm working on integrating a UI library I wrote with it for web support, but I've run into a small issue - it looks like events can't be removed from Elements on-the-fly. I assumed this was a JavaScript limitation, but it appears to work fine in JavaScript in Firefox ("Mozilla/5.0 (X11; Linux x86_64; rv:136.0) Gecko/20100101 Firefox/136.0" ) and Chromium ('Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36')
Here's a demo HTML file:
<html>
<head>
<title>Fengari bug demo</title>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/fengari-web.min.js"></script>
</head>
<body>
<button id="btn-lua">Lua button</button>
<button id="btn-js">JS button</button>
<script type="application/lua" async>
local document = require("js").global.document
local btn = document:querySelector("#btn-lua")
local handler
handler = function ()
print("Button click lua")
btn:removeEventListener("click", handler)
end
btn:addEventListener("click", handler)
</script>
<script>
const btn = document.querySelector("#btn-js")
let handler
handler = function () {
console.log("Button click js")
btn.removeEventListener("click", handler)
}
btn.addEventListener("click", handler)
</script>
</body>
</html>In the lua script, btn:removeEventListener fails to work, which can be checked by clicking the "Lua button" multiple times. I tried to get around this with setTimeout to no avail.
Removing the event listener right after adding it does not work ether:
btn:addEventListener("click", handler)
btn:removeEventListener("click", handler)