PersistedState: add `remove` to remove persisted state from storage

[ibilux]

Describe the feature in detail (code, mocks, or screenshots encouraged)

Can you add a remove function to remove persisted state from storage like window.localstorage.removeitem ?

What type of pull request would this be?

Enhancement

Provide relevant links or additional information.

No response

[noobmaster19]

would love this!

[huntabyte]

We need to think through what handling this gracefully would look like. Would the state still contain a value it would just be disconnected from local storage persistence?

[ibilux]

We need to think through what handling this gracefully would look like. Would the state still contain a value it would just be disconnected from local storage persistence?

the Storage: removeItem() method will remove and set the item to null.

the remove method can be implemented easily like this:

	remove(): void { // <-- 2. The new remove method
		this.#storage?.removeItem(this.#key);
		this.#version += 1;
	}

and we can handle storage event like this? or should we just deserialize it ? (i'm not sure if the deserialize method can handle null values)

	#handleStorageEvent = (event: StorageEvent): void => {
		if (event.key !== this.#key) return;
		if (event.newValue === null) {
			this.#current = null;
		} else {
			this.#current = this.#deserialize(event.newValue);
		}
		this.#version += 1;
	};

but the biggest problem would be the constructor method. we can do this (but i'm not sure if it's practical?).

	constructor(key: string, initialValue: T | null, options: PersistedStateOptions<T> = {}) {
		...
		if (existingValue !== null) {
			this.#current = this.#deserialize(existingValue);
		} else if (initialValue !== null) {
			this.#serialize(initialValue);
		}
		...
	}

[huntabyte]

I'm more concerned about the storage listener, if we remove something from storage it would be re-added on a refresh or value change no?

[ibilux]

I'm more concerned about the storage listener, if we remove something from storage it would be re-added on a refresh or value change no?

I have tested it in a minimal project and it seems to be working. You can test it furthermore at this link:

https://www.sveltelab.dev/o5fxn97tv62vfco

[huntabyte]

What do you all think about #359 ? Does this meet your needs?

[ibilux]

What do you all think about #359 ? Does this meet your needs?

Yes, the disconnect() method remove the persisted state from storage and it's what I needed.

Thank you.