shelving/store/BusyStore.js

Toolkit for using data in JavaScript.

import { awaitDispose } from "../util/dispose.js";
import { BooleanStore } from "./BooleanStore.js";
import { Store } from "./Store.js";
/**
 * Store that tracks its busy status via a separate `this.busy` store.
 * - "busy" means the store is awaiting a new value.
 */
export class BusyStore extends Store {
    busy = new BooleanStore(false);
    // Overload to set `this.busy` to `true` when we start awaiting a value.
    // Gets set back to `false` when `abort()` is called (this also happens whenever a value or reason is set).
    await(pending) {
        this.busy.value = true;
        return super.await(pending);
    }
    // Override to set busy to false on abort.
    // This also happens whenever a value or reaosn is set.
    abort() {
        this.busy.value = false;
        super.abort();
    }
    // Implement `AsyncDisposable`.
    async [Symbol.asyncDispose]() {
        await awaitDispose(() => this.abort(), this.busy, // Send `done: true` to any iterators of the busy store.
        super[Symbol.asyncDispose]());
    }
}