vue-hello/node_modules/copy-webpack-plugin/dist/utils.js

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.readFile = readFile;
exports.stat = stat;
exports.throttleAll = throttleAll;

function stat(inputFileSystem, path) {
  return new Promise((resolve, reject) => {
    inputFileSystem.stat(path, (err, stats) => {
      if (err) {
        reject(err);
      }

      resolve(stats);
    });
  });
}

function readFile(inputFileSystem, path) {
  return new Promise((resolve, reject) => {
    inputFileSystem.readFile(path, (err, stats) => {
      if (err) {
        reject(err);
      }

      resolve(stats);
    });
  });
}

const notSettled = Symbol(`not-settled`);
/**
 * Run tasks with limited concurency.
 * @template T
 * @param {number} limit - Limit of tasks that run at once.
 * @param {Task<T>[]} tasks - List of tasks to run.
 * @returns {Promise<T[]>} A promise that fulfills to an array of the results
 */

function throttleAll(limit, tasks) {
  if (!Number.isInteger(limit) || limit < 1) {
    throw new TypeError(`Expected \`limit\` to be a finite number > 0, got \`${limit}\` (${typeof limit})`);
  }

  if (!Array.isArray(tasks) || !tasks.every(task => typeof task === `function`)) {
    throw new TypeError(`Expected \`tasks\` to be a list of functions returning a promise`);
  }

  return new Promise((resolve, reject) => {
    const result = Array(tasks.length).fill(notSettled);
    const entries = tasks.entries();

    const next = () => {
      const {
        done,
        value
      } = entries.next();

      if (done) {
        const isLast = !result.includes(notSettled);

        if (isLast) {
          resolve(
          /** @type{T[]} **/
          result);
        }

        return;
      }

      const [index, task] = value;
      /**
       * @param {T} x
       */

      const onFulfilled = x => {
        result[index] = x;
        next();
      };

      task().then(onFulfilled, reject);
    };

    Array(limit).fill(0).forEach(next);
  });
}