[Advanced Select, Dropdown, ...] Memory leak when calling autoInit() repeatedly (e.g. due to ajax)

[oliverhaas]

Summary

Calling autoInit() repeatedly will lead to a memory leak

Steps to Reproduce

1. Have a page with Advanced Select or Dropdown (possibly more)
2. Use autoInit() with ajax like described in the docs https://preline.co/docs/preline-javascript.html
3. With every ajax request, duplicate event listeners are registered on the window
   

Demo Link

None

Expected Behavior

No response

Actual Behavior

No response

Screenshots

No response

[oliverhaas]

The code responsible is (Advanced Select as an example, comments by me)

        // src/plugins/select/index.ts
	static autoInit() {
		if (!window.$hsSelectCollection) window.$hsSelectCollection = [];

		document
			.querySelectorAll('[data-hs-select]:not(.--prevent-on-load-init)')
			.forEach((el: HTMLElement) => {
				if (
					!window.$hsSelectCollection.find(
						(elC) => (elC?.element?.el as HTMLElement) === el,
					)
				) {
					const data = el.getAttribute('data-hs-select');
					const options: ISelectOptions = data ? JSON.parse(data) : {};

					new HSSelect(el, options);
				}
			});

                // this code block is basically always run after the first autoInit(), and registers the same event listeners over and over again.
		if (window.$hsSelectCollection) {
			window.addEventListener('click', (evt) => {
				const evtTarget = evt.target;

				HSSelect.closeCurrentlyOpened(evtTarget as HTMLElement);
			});

			document.addEventListener('keydown', (evt) =>
				HSSelect.accessibility(evt),
			);
		}
	}

From what I can tell, a quick fix would look like this

	static autoInit() {
		if (!window.$hsSelectCollection) {
			window.$hsSelectCollection = [];
			window.addEventListener('click', (evt) => {
				const evtTarget = evt.target;

				HSSelect.closeCurrentlyOpened(evtTarget as HTMLElement);
			});

			document.addEventListener('keydown', (evt) =>
				HSSelect.accessibility(evt),
			);
		}

		document
			.querySelectorAll('[data-hs-select]:not(.--prevent-on-load-init)')
			.forEach((el: HTMLElement) => {
				if (
					!window.$hsSelectCollection.find(
						(elC) => (elC?.element?.el as HTMLElement) === el,
					)
				) {
					const data = el.getAttribute('data-hs-select');
					const options: ISelectOptions = data ? JSON.parse(data) : {};

					new HSSelect(el, options);
				}
			});
	}

Sorry, I can't provide more right now. I hope it's enough for now to get this out of the door.

[oliverhaas]

Here a PR which addresses this issue.

#441

[olegpix]

@oliverhaas Hi,
Thank you for your work, we really appreciate it.
We will check the PR and approve it as soon as possible.