@graphql-tools/load/esm/utils/queue.js

A set of utils for faster development of GraphQL tools

function isThenable(value) {
    return value != null && typeof value.then === 'function';
}
export function useQueue(options) {
    const tasks = [];
    const concurrency = options?.concurrency;
    return {
        add(fn) {
            tasks.push(fn);
        },
        runAll() {
            const total = tasks.length;
            if (total === 0) {
                return;
            }
            const limit = concurrency ?? total;
            let index = 0;
            let activeCount = 0;
            let settledCount = 0;
            let failed = false;
            let resolveDone;
            let rejectDone;
            let donePromise;
            const ensureDonePromise = () => {
                if (!donePromise) {
                    ({
                        promise: donePromise,
                        resolve: resolveDone,
                        reject: rejectDone,
                    } = Promise.withResolvers());
                }
                return donePromise;
            };
            const onSettle = () => {
                settledCount++;
                if (failed) {
                    return;
                }
                if (settledCount === total) {
                    resolveDone?.();
                    return;
                }
                pump();
            };
            const pump = () => {
                while (!failed && activeCount < limit && index < total) {
                    const task = tasks[index++];
                    activeCount++;
                    let result;
                    try {
                        result = task();
                    }
                    catch (error) {
                        failed = true;
                        activeCount--;
                        // If callers are already awaiting the completion gate, reject it.
                        // Otherwise keep the sync failure synchronous.
                        if (rejectDone) {
                            rejectDone(error);
                            return;
                        }
                        throw error;
                    }
                    if (isThenable(result)) {
                        // Only async work needs a completion gate; sync results stay sync.
                        ensureDonePromise();
                        result.then(() => {
                            activeCount--;
                            onSettle();
                        }, error => {
                            failed = true;
                            activeCount--;
                            rejectDone(error);
                        });
                    }
                    else {
                        activeCount--;
                        settledCount++;
                    }
                }
                if (!failed && settledCount === total) {
                    resolveDone?.();
                }
            };
            pump();
            if (failed) {
                return donePromise;
            }
            if (settledCount === total) {
                return;
            }
            return ensureDonePromise();
        },
    };
}
export function useSyncQueue() {
    const queue = [];
    return {
        add(fn) {
            queue.push(fn);
        },
        runAll() {
            for (const fn of queue) {
                fn();
            }
        },
    };
}