asyncEachOfLimit.js 1.93 KB
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'use strict';

Object.defineProperty(exports, "__esModule", {
    value: true
});
exports.default = asyncEachOfLimit;

var _breakLoop = require('./breakLoop.js');

var _breakLoop2 = _interopRequireDefault(_breakLoop);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

// for async generators
function asyncEachOfLimit(generator, limit, iteratee, callback) {
    let done = false;
    let canceled = false;
    let awaiting = false;
    let running = 0;
    let idx = 0;

    function replenish() {
        //console.log('replenish')
        if (running >= limit || awaiting || done) return;
        //console.log('replenish awaiting')
        awaiting = true;
        generator.next().then(({ value, done: iterDone }) => {
            //console.log('got value', value)
            if (canceled || done) return;
            awaiting = false;
            if (iterDone) {
                done = true;
                if (running <= 0) {
                    //console.log('done nextCb')
                    callback(null);
                }
                return;
            }
            running++;
            iteratee(value, idx, iterateeCallback);
            idx++;
            replenish();
        }).catch(handleError);
    }

    function iterateeCallback(err, result) {
        //console.log('iterateeCallback')
        running -= 1;
        if (canceled) return;
        if (err) return handleError(err);

        if (err === false) {
            done = true;
            canceled = true;
            return;
        }

        if (result === _breakLoop2.default || done && running <= 0) {
            done = true;
            //console.log('done iterCb')
            return callback(null);
        }
        replenish();
    }

    function handleError(err) {
        if (canceled) return;
        awaiting = false;
        done = true;
        callback(err);
    }

    replenish();
}
module.exports = exports['default'];