node_modules/async/internal/DoublyLinkedList.js

+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+// Simple doubly linked list (https://en.wikipedia.org/wiki/Doubly_linked_list) implementation
+// used for queues. This implementation assumes that the node provided by the user can be modified
+// to adjust the next and last properties. We implement only the minimal functionality
+// for queue support.
+class DLL {
+    constructor() {
+        this.head = this.tail = null;
+        this.length = 0;
+    }
+
+    removeLink(node) {
+        if (node.prev) node.prev.next = node.next;else this.head = node.next;
+        if (node.next) node.next.prev = node.prev;else this.tail = node.prev;
+
+        node.prev = node.next = null;
+        this.length -= 1;
+        return node;
+    }
+
+    empty() {
+        while (this.head) this.shift();
+        return this;
+    }
+
+    insertAfter(node, newNode) {
+        newNode.prev = node;
+        newNode.next = node.next;
+        if (node.next) node.next.prev = newNode;else this.tail = newNode;
+        node.next = newNode;
+        this.length += 1;
+    }
+
+    insertBefore(node, newNode) {
+        newNode.prev = node.prev;
+        newNode.next = node;
+        if (node.prev) node.prev.next = newNode;else this.head = newNode;
+        node.prev = newNode;
+        this.length += 1;
+    }
+
+    unshift(node) {
+        if (this.head) this.insertBefore(this.head, node);else setInitial(this, node);
+    }
+
+    push(node) {
+        if (this.tail) this.insertAfter(this.tail, node);else setInitial(this, node);
+    }
+
+    shift() {
+        return this.head && this.removeLink(this.head);
+    }
+
+    pop() {
+        return this.tail && this.removeLink(this.tail);
+    }
+
+    toArray() {
+        return [...this];
+    }
+
+    *[Symbol.iterator]() {
+        var cur = this.head;
+        while (cur) {
+            yield cur.data;
+            cur = cur.next;
+        }
+    }
+
+    remove(testFn) {
+        var curr = this.head;
+        while (curr) {
+            var { next } = curr;
+            if (testFn(curr)) {
+                this.removeLink(curr);
+            }
+            curr = next;
+        }
+        return this;
+    }
+}
+
+exports.default = DLL;
+function setInitial(dll, node) {
+    dll.length = 1;
+    dll.head = dll.tail = node;
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/Heap.js

+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+// Binary min-heap implementation used for priority queue.
+// Implementation is stable, i.e. push time is considered for equal priorities
+class Heap {
+    constructor() {
+        this.heap = [];
+        this.pushCount = Number.MIN_SAFE_INTEGER;
+    }
+
+    get length() {
+        return this.heap.length;
+    }
+
+    empty() {
+        this.heap = [];
+        return this;
+    }
+
+    percUp(index) {
+        let p;
+
+        while (index > 0 && smaller(this.heap[index], this.heap[p = parent(index)])) {
+            let t = this.heap[index];
+            this.heap[index] = this.heap[p];
+            this.heap[p] = t;
+
+            index = p;
+        }
+    }
+
+    percDown(index) {
+        let l;
+
+        while ((l = leftChi(index)) < this.heap.length) {
+            if (l + 1 < this.heap.length && smaller(this.heap[l + 1], this.heap[l])) {
+                l = l + 1;
+            }
+
+            if (smaller(this.heap[index], this.heap[l])) {
+                break;
+            }
+
+            let t = this.heap[index];
+            this.heap[index] = this.heap[l];
+            this.heap[l] = t;
+
+            index = l;
+        }
+    }
+
+    push(node) {
+        node.pushCount = ++this.pushCount;
+        this.heap.push(node);
+        this.percUp(this.heap.length - 1);
+    }
+
+    unshift(node) {
+        return this.heap.push(node);
+    }
+
+    shift() {
+        let [top] = this.heap;
+
+        this.heap[0] = this.heap[this.heap.length - 1];
+        this.heap.pop();
+        this.percDown(0);
+
+        return top;
+    }
+
+    toArray() {
+        return [...this];
+    }
+
+    *[Symbol.iterator]() {
+        for (let i = 0; i < this.heap.length; i++) {
+            yield this.heap[i].data;
+        }
+    }
+
+    remove(testFn) {
+        let j = 0;
+        for (let i = 0; i < this.heap.length; i++) {
+            if (!testFn(this.heap[i])) {
+                this.heap[j] = this.heap[i];
+                j++;
+            }
+        }
+
+        this.heap.splice(j);
+
+        for (let i = parent(this.heap.length - 1); i >= 0; i--) {
+            this.percDown(i);
+        }
+
+        return this;
+    }
+}
+
+exports.default = Heap;
+function leftChi(i) {
+    return (i << 1) + 1;
+}
+
+function parent(i) {
+    return (i + 1 >> 1) - 1;
+}
+
+function smaller(x, y) {
+    if (x.priority !== y.priority) {
+        return x.priority < y.priority;
+    } else {
+        return x.pushCount < y.pushCount;
+    }
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/applyEach.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+
+exports.default = function (eachfn) {
+    return function applyEach(fns, ...callArgs) {
+        const go = (0, _awaitify2.default)(function (callback) {
+            var that = this;
+            return eachfn(fns, (fn, cb) => {
+                (0, _wrapAsync2.default)(fn).apply(that, callArgs.concat(cb));
+            }, callback);
+        });
+        return go;
+    };
+};
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+var _awaitify = require('./awaitify.js');
+
+var _awaitify2 = _interopRequireDefault(_awaitify);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/asyncEachOfLimit.js

+'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;
\ No newline at end of file

node_modules/async/internal/awaitify.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = awaitify;
+// conditionally promisify a function.
+// only return a promise if a callback is omitted
+function awaitify(asyncFn, arity) {
+    if (!arity) arity = asyncFn.length;
+    if (!arity) throw new Error('arity is undefined');
+    function awaitable(...args) {
+        if (typeof args[arity - 1] === 'function') {
+            return asyncFn.apply(this, args);
+        }
+
+        return new Promise((resolve, reject) => {
+            args[arity - 1] = (err, ...cbArgs) => {
+                if (err) return reject(err);
+                resolve(cbArgs.length > 1 ? cbArgs : cbArgs[0]);
+            };
+            asyncFn.apply(this, args);
+        });
+    }
+
+    return awaitable;
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/breakLoop.js

+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+// A temporary value used to identify if the loop should be broken.
+// See #1064, #1293
+const breakLoop = {};
+exports.default = breakLoop;
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/consoleFunc.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = consoleFunc;
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function consoleFunc(name) {
+    return (fn, ...args) => (0, _wrapAsync2.default)(fn)(...args, (err, ...resultArgs) => {
+        /* istanbul ignore else */
+        if (typeof console === 'object') {
+            /* istanbul ignore else */
+            if (err) {
+                /* istanbul ignore else */
+                if (console.error) {
+                    console.error(err);
+                }
+            } else if (console[name]) {
+                /* istanbul ignore else */
+                resultArgs.forEach(x => console[name](x));
+            }
+        }
+    });
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/createTester.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = _createTester;
+
+var _breakLoop = require('./breakLoop.js');
+
+var _breakLoop2 = _interopRequireDefault(_breakLoop);
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function _createTester(check, getResult) {
+    return (eachfn, arr, _iteratee, cb) => {
+        var testPassed = false;
+        var testResult;
+        const iteratee = (0, _wrapAsync2.default)(_iteratee);
+        eachfn(arr, (value, _, callback) => {
+            iteratee(value, (err, result) => {
+                if (err || err === false) return callback(err);
+
+                if (check(result) && !testResult) {
+                    testPassed = true;
+                    testResult = getResult(true, value);
+                    return callback(null, _breakLoop2.default);
+                }
+                callback();
+            });
+        }, err => {
+            if (err) return cb(err);
+            cb(null, testPassed ? testResult : getResult(false));
+        });
+    };
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/eachOfLimit.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+
+var _once = require('./once.js');
+
+var _once2 = _interopRequireDefault(_once);
+
+var _iterator = require('./iterator.js');
+
+var _iterator2 = _interopRequireDefault(_iterator);
+
+var _onlyOnce = require('./onlyOnce.js');
+
+var _onlyOnce2 = _interopRequireDefault(_onlyOnce);
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _asyncEachOfLimit = require('./asyncEachOfLimit.js');
+
+var _asyncEachOfLimit2 = _interopRequireDefault(_asyncEachOfLimit);
+
+var _breakLoop = require('./breakLoop.js');
+
+var _breakLoop2 = _interopRequireDefault(_breakLoop);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+exports.default = limit => {
+    return (obj, iteratee, callback) => {
+        callback = (0, _once2.default)(callback);
+        if (limit <= 0) {
+            throw new RangeError('concurrency limit cannot be less than 1');
+        }
+        if (!obj) {
+            return callback(null);
+        }
+        if ((0, _wrapAsync.isAsyncGenerator)(obj)) {
+            return (0, _asyncEachOfLimit2.default)(obj, limit, iteratee, callback);
+        }
+        if ((0, _wrapAsync.isAsyncIterable)(obj)) {
+            return (0, _asyncEachOfLimit2.default)(obj[Symbol.asyncIterator](), limit, iteratee, callback);
+        }
+        var nextElem = (0, _iterator2.default)(obj);
+        var done = false;
+        var canceled = false;
+        var running = 0;
+        var looping = false;
+
+        function iterateeCallback(err, value) {
+            if (canceled) return;
+            running -= 1;
+            if (err) {
+                done = true;
+                callback(err);
+            } else if (err === false) {
+                done = true;
+                canceled = true;
+            } else if (value === _breakLoop2.default || done && running <= 0) {
+                done = true;
+                return callback(null);
+            } else if (!looping) {
+                replenish();
+            }
+        }
+
+        function replenish() {
+            looping = true;
+            while (running < limit && !done) {
+                var elem = nextElem();
+                if (elem === null) {
+                    done = true;
+                    if (running <= 0) {
+                        callback(null);
+                    }
+                    return;
+                }
+                running += 1;
+                iteratee(elem.value, elem.key, (0, _onlyOnce2.default)(iterateeCallback));
+            }
+            looping = false;
+        }
+
+        replenish();
+    };
+};
+
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/filter.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = _filter;
+
+var _isArrayLike = require('./isArrayLike.js');
+
+var _isArrayLike2 = _interopRequireDefault(_isArrayLike);
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function filterArray(eachfn, arr, iteratee, callback) {
+    var truthValues = new Array(arr.length);
+    eachfn(arr, (x, index, iterCb) => {
+        iteratee(x, (err, v) => {
+            truthValues[index] = !!v;
+            iterCb(err);
+        });
+    }, err => {
+        if (err) return callback(err);
+        var results = [];
+        for (var i = 0; i < arr.length; i++) {
+            if (truthValues[i]) results.push(arr[i]);
+        }
+        callback(null, results);
+    });
+}
+
+function filterGeneric(eachfn, coll, iteratee, callback) {
+    var results = [];
+    eachfn(coll, (x, index, iterCb) => {
+        iteratee(x, (err, v) => {
+            if (err) return iterCb(err);
+            if (v) {
+                results.push({ index, value: x });
+            }
+            iterCb(err);
+        });
+    }, err => {
+        if (err) return callback(err);
+        callback(null, results.sort((a, b) => a.index - b.index).map(v => v.value));
+    });
+}
+
+function _filter(eachfn, coll, iteratee, callback) {
+    var filter = (0, _isArrayLike2.default)(coll) ? filterArray : filterGeneric;
+    return filter(eachfn, coll, (0, _wrapAsync2.default)(iteratee), callback);
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/getIterator.js

+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+
+exports.default = function (coll) {
+    return coll[Symbol.iterator] && coll[Symbol.iterator]();
+};
+
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/initialParams.js

+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+
+exports.default = function (fn) {
+    return function (...args /*, callback*/) {
+        var callback = args.pop();
+        return fn.call(this, args, callback);
+    };
+};
+
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/isArrayLike.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = isArrayLike;
+function isArrayLike(value) {
+    return value && typeof value.length === 'number' && value.length >= 0 && value.length % 1 === 0;
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/iterator.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = createIterator;
+
+var _isArrayLike = require('./isArrayLike.js');
+
+var _isArrayLike2 = _interopRequireDefault(_isArrayLike);
+
+var _getIterator = require('./getIterator.js');
+
+var _getIterator2 = _interopRequireDefault(_getIterator);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function createArrayIterator(coll) {
+    var i = -1;
+    var len = coll.length;
+    return function next() {
+        return ++i < len ? { value: coll[i], key: i } : null;
+    };
+}
+
+function createES2015Iterator(iterator) {
+    var i = -1;
+    return function next() {
+        var item = iterator.next();
+        if (item.done) return null;
+        i++;
+        return { value: item.value, key: i };
+    };
+}
+
+function createObjectIterator(obj) {
+    var okeys = obj ? Object.keys(obj) : [];
+    var i = -1;
+    var len = okeys.length;
+    return function next() {
+        var key = okeys[++i];
+        if (key === '__proto__') {
+            return next();
+        }
+        return i < len ? { value: obj[key], key } : null;
+    };
+}
+
+function createIterator(coll) {
+    if ((0, _isArrayLike2.default)(coll)) {
+        return createArrayIterator(coll);
+    }
+
+    var iterator = (0, _getIterator2.default)(coll);
+    return iterator ? createES2015Iterator(iterator) : createObjectIterator(coll);
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/map.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = _asyncMap;
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function _asyncMap(eachfn, arr, iteratee, callback) {
+    arr = arr || [];
+    var results = [];
+    var counter = 0;
+    var _iteratee = (0, _wrapAsync2.default)(iteratee);
+
+    return eachfn(arr, (value, _, iterCb) => {
+        var index = counter++;
+        _iteratee(value, (err, v) => {
+            results[index] = v;
+            iterCb(err);
+        });
+    }, err => {
+        callback(err, results);
+    });
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/once.js

+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = once;
+function once(fn) {
+    function wrapper(...args) {
+        if (fn === null) return;
+        var callFn = fn;
+        fn = null;
+        callFn.apply(this, args);
+    }
+    Object.assign(wrapper, fn);
+    return wrapper;
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/onlyOnce.js

+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = onlyOnce;
+function onlyOnce(fn) {
+    return function (...args) {
+        if (fn === null) throw new Error("Callback was already called.");
+        var callFn = fn;
+        fn = null;
+        callFn.apply(this, args);
+    };
+}
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/parallel.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+
+var _isArrayLike = require('./isArrayLike.js');
+
+var _isArrayLike2 = _interopRequireDefault(_isArrayLike);
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+var _awaitify = require('./awaitify.js');
+
+var _awaitify2 = _interopRequireDefault(_awaitify);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+exports.default = (0, _awaitify2.default)((eachfn, tasks, callback) => {
+    var results = (0, _isArrayLike2.default)(tasks) ? [] : {};
+
+    eachfn(tasks, (task, key, taskCb) => {
+        (0, _wrapAsync2.default)(task)((err, ...result) => {
+            if (result.length < 2) {
+                [result] = result;
+            }
+            results[key] = result;
+            taskCb(err);
+        });
+    }, err => callback(err, results));
+}, 3);
+module.exports = exports.default;
\ No newline at end of file

node_modules/async/internal/promiseCallback.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+const PROMISE_SYMBOL = Symbol('promiseCallback');
+
+function promiseCallback() {
+    let resolve, reject;
+    function callback(err, ...args) {
+        if (err) return reject(err);
+        resolve(args.length > 1 ? args : args[0]);
+    }
+
+    callback[PROMISE_SYMBOL] = new Promise((res, rej) => {
+        resolve = res, reject = rej;
+    });
+
+    return callback;
+}
+
+exports.promiseCallback = promiseCallback;
+exports.PROMISE_SYMBOL = PROMISE_SYMBOL;
\ No newline at end of file

node_modules/async/internal/queue.js

+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = queue;
+
+var _onlyOnce = require('./onlyOnce.js');
+
+var _onlyOnce2 = _interopRequireDefault(_onlyOnce);
+
+var _setImmediate = require('./setImmediate.js');
+
+var _setImmediate2 = _interopRequireDefault(_setImmediate);
+
+var _DoublyLinkedList = require('./DoublyLinkedList.js');
+
+var _DoublyLinkedList2 = _interopRequireDefault(_DoublyLinkedList);
+
+var _wrapAsync = require('./wrapAsync.js');
+
+var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function queue(worker, concurrency, payload) {
+    if (concurrency == null) {
+        concurrency = 1;
+    } else if (concurrency === 0) {
+        throw new RangeError('Concurrency must not be zero');
+    }
+
+    var _worker = (0, _wrapAsync2.default)(worker);
+    var numRunning = 0;
+    var workersList = [];
+    const events = {
+        error: [],
+        drain: [],
+        saturated: [],
+        unsaturated: [],
+        empty: []
+    };
+
+    function on(event, handler) {
+        events[event].push(handler);
+    }
+
+    function once(event, handler) {
+        const handleAndRemove = (...args) => {
+            off(event, handleAndRemove);
+            handler(...args);
+        };
+        events[event].push(handleAndRemove);
+    }
+
+    function off(event, handler) {
+        if (!event) return Object.keys(events).forEach(ev => events[ev] = []);
+        if (!handler) return events[event] = [];
+        events[event] = events[event].filter(ev => ev !== handler);
+    }
+
+    function trigger(event, ...args) {
+        events[event].forEach(handler => handler(...args));
+    }
+
+    var processingScheduled = false;
+    function _insert(data, insertAtFront, rejectOnError, callback) {
+        if (callback != null && typeof callback !== 'function') {
+            throw new Error('task callback must be a function');
+        }
+        q.started = true;
+
+        var res, rej;
+        function promiseCallback(err, ...args) {
+            // we don't care about the error, let the global error handler
+            // deal with it
+            if (err) return rejectOnError ? rej(err) : res();
+            if (args.length <= 1) return res(args[0]);
+            res(args);
+        }
+
+        var item = q._createTaskItem(data, rejectOnError ? promiseCallback : callback || promiseCallback);
+
+        if (insertAtFront) {
+            q._tasks.unshift(item);
+        } else {
+            q._tasks.push(item);
+        }
+
+        if (!processingScheduled) {
+            processingScheduled = true;
+            (0, _setImmediate2.default)(() => {
+                processingScheduled = false;
+                q.process();
+            });
+        }
+
+        if (rejectOnError || !callback) {
+            return new Promise((resolve, reject) => {
+                res = resolve;
+                rej = reject;
+            });
+        }
+    }
+
+    function _createCB(tasks) {
+        return function (err, ...args) {
+            numRunning -= 1;
+
+            for (var i = 0, l = tasks.length; i < l; i++) {
+                var task = tasks[i];
+
+                var index = workersList.indexOf(task);
+                if (index === 0) {
+                    workersList.shift();
+                } else if (index > 0) {
+                    workersList.splice(index, 1);
+                }
+
+                task.callback(err, ...args);
+
+                if (err != null) {
+                    trigger('error', err, task.data);
+                }
+            }
+
+            if (numRunning <= q.concurrency - q.buffer) {
+                trigger('unsaturated');
+            }
+
+            if (q.idle()) {
+                trigger('drain');
+            }
+            q.process();
+        };
+    }
+
+    function _maybeDrain(data) {
+        if (data.length === 0 && q.idle()) {
+            // call drain immediately if there are no tasks
+            (0, _setImmediate2.default)(() => trigger('drain'));
+            return true;
+        }
+        return false;
+    }
+
+    const eventMethod = name => handler => {
+        if (!handler) {
+            return new Promise((resolve, reject) => {
+                once(name, (err, data) => {
+                    if (err) return reject(err);
+                    resolve(data);
+                });
+            });
+        }
+        off(name);
+        on(name, handler);
+    };
+
+    var isProcessing = false;
+    var q = {
+        _tasks: new _DoublyLinkedList2.default(),
+        _createTaskItem(data, callback) {
+            return {
+                data,
+                callback
+            };
+        },
+        *[Symbol.iterator]() {
+            yield* q._tasks[Symbol.iterator]();
+        },
+        concurrency,
+        payload,
+        buffer: concurrency / 4,
+        started: false,
+        paused: false,
+        push(data, callback) {
+            if (Array.isArray(data)) {
+                if (_maybeDrain(data)) return;
+                return data.map(datum => _insert(datum, false, false, callback));
+            }
+            return _insert(data, false, false, callback);
+        },
+        pushAsync(data, callback) {
+            if (Array.isArray(data)) {
+                if (_maybeDrain(data)) return;
+                return data.map(datum => _insert(datum, false, true, callback));
+            }
+            return _insert(data, false, true, callback);
+        },
+        kill() {
+            off();
+            q._tasks.empty();
+        },
+        unshift(data, callback) {
+            if (Array.isArray(data)) {
+                if (_maybeDrain(data)) return;
+                return data.map(datum => _insert(datum, true, false, callback));
+            }
+            return _insert(data, true, false, callback);
+        },
+        unshiftAsync(data, callback) {
+            if (Array.isArray(data)) {
+                if (_maybeDrain(data)) return;
+                return data.map(datum => _insert(datum, true, true, callback));
+            }
+            return _insert(data, true, true, callback);
+        },
+        remove(testFn) {
+            q._tasks.remove(testFn);
+        },
+        process() {
+            // Avoid trying to start too many processing operations. This can occur
+            // when callbacks resolve synchronously (#1267).
+            if (isProcessing) {
+                return;
+            }
+            isProcessing = true;
+            while (!q.paused && numRunning < q.concurrency && q._tasks.length) {
+                var tasks = [],
+                    data = [];
+                var l = q._tasks.length;
+                if (q.payload) l = Math.min(l, q.payload);
+                for (var i = 0; i < l; i++) {
+                    var node = q._tasks.shift();
+                    tasks.push(node);
+                    workersList.push(node);
+                    data.push(node.data);
+                }
+
+                numRunning += 1;
+
+                if (q._tasks.length === 0) {
+                    trigger('empty');
+                }
+
+                if (numRunning === q.concurrency) {
+                    trigger('saturated');
+                }
+
+                var cb = (0, _onlyOnce2.default)(_createCB(tasks));
+                _worker(data, cb);
+            }
+            isProcessing = false;
+        },
+        length() {
+            return q._tasks.length;
+        },
+        running() {
+            return numRunning;
+        },
+        workersList() {
+            return workersList;
+        },
+        idle() {
+            return q._tasks.length + numRunning === 0;
+        },
+        pause() {
+            q.paused = true;
+        },
+        resume() {
+            if (q.paused === false) {
+                return;
+            }
+            q.paused = false;
+            (0, _setImmediate2.default)(q.process);
+        }
+    };
+    // define these as fixed properties, so people get useful errors when updating
+    Object.defineProperties(q, {
+        saturated: {
+            writable: false,
+            value: eventMethod('saturated')
+        },
+        unsaturated: {
+            writable: false,
+            value: eventMethod('unsaturated')
+        },
+        empty: {
+            writable: false,
+            value: eventMethod('empty')
+        },
+        drain: {
+            writable: false,
+            value: eventMethod('drain')
+        },
+        error: {
+            writable: false,
+            value: eventMethod('error')
+        }
+    });
+    return q;
+}
+module.exports = exports.default;
\ No newline at end of file