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- 'use strict';
-
- Object.defineProperty(exports, "__esModule", {
- value: true
- });
- exports.default = autoInject;
-
- var _auto = require('./auto');
-
- var _auto2 = _interopRequireDefault(_auto);
-
- var _baseForOwn = require('lodash/_baseForOwn');
-
- var _baseForOwn2 = _interopRequireDefault(_baseForOwn);
-
- var _arrayMap = require('lodash/_arrayMap');
-
- var _arrayMap2 = _interopRequireDefault(_arrayMap);
-
- var _isArray = require('lodash/isArray');
-
- var _isArray2 = _interopRequireDefault(_isArray);
-
- var _trim = require('lodash/trim');
-
- var _trim2 = _interopRequireDefault(_trim);
-
- var _wrapAsync = require('./internal/wrapAsync');
-
- var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
-
- function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
-
- var FN_ARGS = /^(?:async\s+)?(function)?\s*[^\(]*\(\s*([^\)]*)\)/m;
- var FN_ARG_SPLIT = /,/;
- var FN_ARG = /(=.+)?(\s*)$/;
- var STRIP_COMMENTS = /((\/\/.*$)|(\/\*[\s\S]*?\*\/))/mg;
-
- function parseParams(func) {
- func = func.toString().replace(STRIP_COMMENTS, '');
- func = func.match(FN_ARGS)[2].replace(' ', '');
- func = func ? func.split(FN_ARG_SPLIT) : [];
- func = func.map(function (arg) {
- return (0, _trim2.default)(arg.replace(FN_ARG, ''));
- });
- return func;
- }
-
- /**
- * A dependency-injected version of the [async.auto]{@link module:ControlFlow.auto} function. Dependent
- * tasks are specified as parameters to the function, after the usual callback
- * parameter, with the parameter names matching the names of the tasks it
- * depends on. This can provide even more readable task graphs which can be
- * easier to maintain.
- *
- * If a final callback is specified, the task results are similarly injected,
- * specified as named parameters after the initial error parameter.
- *
- * The autoInject function is purely syntactic sugar and its semantics are
- * otherwise equivalent to [async.auto]{@link module:ControlFlow.auto}.
- *
- * @name autoInject
- * @static
- * @memberOf module:ControlFlow
- * @method
- * @see [async.auto]{@link module:ControlFlow.auto}
- * @category Control Flow
- * @param {Object} tasks - An object, each of whose properties is an {@link AsyncFunction} of
- * the form 'func([dependencies...], callback). The object's key of a property
- * serves as the name of the task defined by that property, i.e. can be used
- * when specifying requirements for other tasks.
- * * The `callback` parameter is a `callback(err, result)` which must be called
- * when finished, passing an `error` (which can be `null`) and the result of
- * the function's execution. The remaining parameters name other tasks on
- * which the task is dependent, and the results from those tasks are the
- * arguments of those parameters.
- * @param {Function} [callback] - An optional callback which is called when all
- * the tasks have been completed. It receives the `err` argument if any `tasks`
- * pass an error to their callback, and a `results` object with any completed
- * task results, similar to `auto`.
- * @example
- *
- * // The example from `auto` can be rewritten as follows:
- * async.autoInject({
- * get_data: function(callback) {
- * // async code to get some data
- * callback(null, 'data', 'converted to array');
- * },
- * make_folder: function(callback) {
- * // async code to create a directory to store a file in
- * // this is run at the same time as getting the data
- * callback(null, 'folder');
- * },
- * write_file: function(get_data, make_folder, callback) {
- * // once there is some data and the directory exists,
- * // write the data to a file in the directory
- * callback(null, 'filename');
- * },
- * email_link: function(write_file, callback) {
- * // once the file is written let's email a link to it...
- * // write_file contains the filename returned by write_file.
- * callback(null, {'file':write_file, 'email':'user@example.com'});
- * }
- * }, function(err, results) {
- * console.log('err = ', err);
- * console.log('email_link = ', results.email_link);
- * });
- *
- * // If you are using a JS minifier that mangles parameter names, `autoInject`
- * // will not work with plain functions, since the parameter names will be
- * // collapsed to a single letter identifier. To work around this, you can
- * // explicitly specify the names of the parameters your task function needs
- * // in an array, similar to Angular.js dependency injection.
- *
- * // This still has an advantage over plain `auto`, since the results a task
- * // depends on are still spread into arguments.
- * async.autoInject({
- * //...
- * write_file: ['get_data', 'make_folder', function(get_data, make_folder, callback) {
- * callback(null, 'filename');
- * }],
- * email_link: ['write_file', function(write_file, callback) {
- * callback(null, {'file':write_file, 'email':'user@example.com'});
- * }]
- * //...
- * }, function(err, results) {
- * console.log('err = ', err);
- * console.log('email_link = ', results.email_link);
- * });
- */
- function autoInject(tasks, callback) {
- var newTasks = {};
-
- (0, _baseForOwn2.default)(tasks, function (taskFn, key) {
- var params;
- var fnIsAsync = (0, _wrapAsync.isAsync)(taskFn);
- var hasNoDeps = !fnIsAsync && taskFn.length === 1 || fnIsAsync && taskFn.length === 0;
-
- if ((0, _isArray2.default)(taskFn)) {
- params = taskFn.slice(0, -1);
- taskFn = taskFn[taskFn.length - 1];
-
- newTasks[key] = params.concat(params.length > 0 ? newTask : taskFn);
- } else if (hasNoDeps) {
- // no dependencies, use the function as-is
- newTasks[key] = taskFn;
- } else {
- params = parseParams(taskFn);
- if (taskFn.length === 0 && !fnIsAsync && params.length === 0) {
- throw new Error("autoInject task functions require explicit parameters.");
- }
-
- // remove callback param
- if (!fnIsAsync) params.pop();
-
- newTasks[key] = params.concat(newTask);
- }
-
- function newTask(results, taskCb) {
- var newArgs = (0, _arrayMap2.default)(params, function (name) {
- return results[name];
- });
- newArgs.push(taskCb);
- (0, _wrapAsync2.default)(taskFn).apply(null, newArgs);
- }
- });
-
- (0, _auto2.default)(newTasks, callback);
- }
- module.exports = exports['default'];
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