| /* |
| MIT License http://www.opensource.org/licenses/mit-license.php |
| Author Tobias Koppers @sokra |
| */ |
| "use strict"; |
| |
| /** |
| * Gets the value at path of object |
| * @param {object} obj - object to query |
| * @param {string} path - query path |
| * @returns {any} - if {@param path} requests element from array, then `undefined` will be returned |
| */ |
| const getProperty = (obj, path) => { |
| let name = path.split("."); |
| for (let i = 0; i < name.length - 1; i++) { |
| obj = obj[name[i]]; |
| if (typeof obj !== "object" || !obj || Array.isArray(obj)) return; |
| } |
| return obj[name.pop()]; |
| }; |
| |
| /** |
| * Sets the value at path of object. Stops execution, if {@param path} requests element from array to be set |
| * @param {object} obj - object to query |
| * @param {string} path - query path |
| * @param {any} value - value to be set |
| * @returns {void} |
| */ |
| const setProperty = (obj, path, value) => { |
| let name = path.split("."); |
| for (let i = 0; i < name.length - 1; i++) { |
| if (typeof obj[name[i]] !== "object" && obj[name[i]] !== undefined) return; |
| if (Array.isArray(obj[name[i]])) return; |
| if (!obj[name[i]]) obj[name[i]] = {}; |
| obj = obj[name[i]]; |
| } |
| obj[name.pop()] = value; |
| }; |
| |
| /** |
| * @typedef {'call' | 'make' | 'append'} ConfigType |
| */ |
| /** |
| * @typedef {(options: object) => any} MakeConfigHandler |
| */ |
| /** |
| * @typedef {(value: any, options: object) => any} CallConfigHandler |
| */ |
| /** |
| * @typedef {any[]} AppendConfigValues |
| */ |
| |
| class OptionsDefaulter { |
| constructor() { |
| /** |
| * Stores default options settings or functions for computing them |
| */ |
| this.defaults = {}; |
| /** |
| * Stores configuration for options |
| * @type {{[key: string]: ConfigType}} |
| */ |
| this.config = {}; |
| } |
| |
| /** |
| * Enhancing {@param options} with default values |
| * @param {object} options - provided options |
| * @returns {object} - enhanced options |
| * @throws {Error} - will throw error, if configuration value is other then `undefined` or {@link ConfigType} |
| */ |
| process(options) { |
| options = Object.assign({}, options); |
| for (let name in this.defaults) { |
| switch (this.config[name]) { |
| /** |
| * If {@link ConfigType} doesn't specified and current value is `undefined`, then default value will be assigned |
| */ |
| case undefined: |
| if (getProperty(options, name) === undefined) { |
| setProperty(options, name, this.defaults[name]); |
| } |
| break; |
| /** |
| * Assign result of {@link CallConfigHandler} |
| */ |
| case "call": |
| setProperty( |
| options, |
| name, |
| this.defaults[name].call(this, getProperty(options, name), options) |
| ); |
| break; |
| /** |
| * Assign result of {@link MakeConfigHandler}, if current value is `undefined` |
| */ |
| case "make": |
| if (getProperty(options, name) === undefined) { |
| setProperty(options, name, this.defaults[name].call(this, options)); |
| } |
| break; |
| /** |
| * Adding {@link AppendConfigValues} at the end of the current array |
| */ |
| case "append": { |
| let oldValue = getProperty(options, name); |
| if (!Array.isArray(oldValue)) { |
| oldValue = []; |
| } |
| oldValue.push(...this.defaults[name]); |
| setProperty(options, name, oldValue); |
| break; |
| } |
| default: |
| throw new Error( |
| "OptionsDefaulter cannot process " + this.config[name] |
| ); |
| } |
| } |
| return options; |
| } |
| |
| /** |
| * Builds up default values |
| * @param {string} name - option path |
| * @param {ConfigType | any} config - if {@param def} is provided, then only {@link ConfigType} is allowed |
| * @param {MakeConfigHandler | CallConfigHandler | AppendConfigValues} [def] - defaults |
| * @returns {void} |
| */ |
| set(name, config, def) { |
| if (def !== undefined) { |
| this.defaults[name] = def; |
| this.config[name] = config; |
| } else { |
| this.defaults[name] = config; |
| delete this.config[name]; |
| } |
| } |
| } |
| |
| module.exports = OptionsDefaulter; |