116 lines
3.0 KiB
JavaScript
116 lines
3.0 KiB
JavaScript
|
/**
|
||
|
|
* @fileoverview `Map` to load rules lazily.
|
||
|
|
* @author Toru Nagashima <https://github.com/mysticatea>
|
||
|
|
*/
|
||
|
|
"use strict";
|
||
|
|
|
||
|
|
const debug = require("debug")("eslint:rules");
|
||
|
|
|
||
|
|
/** @typedef {import("./types").Rule} Rule */
|
||
|
|
|
||
|
|
/**
|
||
|
|
* The `Map` object that loads each rule when it's accessed.
|
||
|
|
* @example
|
||
|
|
* const rules = new LazyLoadingRuleMap([
|
||
|
|
* ["eqeqeq", () => require("eqeqeq")],
|
||
|
|
* ["semi", () => require("semi")],
|
||
|
|
* ["no-unused-vars", () => require("no-unused-vars")]
|
||
|
|
* ]);
|
||
|
|
*
|
||
|
|
* rules.get("semi"); // call `() => require("semi")` here.
|
||
|
|
*
|
||
|
|
* @extends {Map<string, () => Rule>}
|
||
|
|
*/
|
||
|
|
class LazyLoadingRuleMap extends Map {
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Initialize this map.
|
||
|
|
* @param {Array<[string, function(): Rule]>} loaders The rule loaders.
|
||
|
|
*/
|
||
|
|
constructor(loaders) {
|
||
|
|
let remaining = loaders.length;
|
||
|
|
|
||
|
|
super(
|
||
|
|
debug.enabled
|
||
|
|
? loaders.map(([ruleId, load]) => {
|
||
|
|
let cache = null;
|
||
|
|
|
||
|
|
return [
|
||
|
|
ruleId,
|
||
|
|
() => {
|
||
|
|
if (!cache) {
|
||
|
|
debug("Loading rule %o (remaining=%d)", ruleId, --remaining);
|
||
|
|
cache = load();
|
||
|
|
}
|
||
|
|
return cache;
|
||
|
|
}
|
||
|
|
];
|
||
|
|
})
|
||
|
|
: loaders
|
||
|
|
);
|
||
|
|
|
||
|
|
// `super(...iterable)` uses `this.set()`, so disable it here.
|
||
|
|
Object.defineProperty(LazyLoadingRuleMap.prototype, "set", {
|
||
|
|
configurable: true,
|
||
|
|
value: void 0
|
||
|
|
});
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Get a rule.
|
||
|
|
* Each rule will be loaded on the first access.
|
||
|
|
* @param {string} ruleId The rule ID to get.
|
||
|
|
* @returns {Rule|undefined} The rule.
|
||
|
|
*/
|
||
|
|
get(ruleId) {
|
||
|
|
const load = super.get(ruleId);
|
||
|
|
|
||
|
|
return load && load();
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Iterate rules.
|
||
|
|
* @returns {IterableIterator<Rule>} Rules.
|
||
|
|
*/
|
||
|
|
*values() {
|
||
|
|
for (const load of super.values()) {
|
||
|
|
yield load();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Iterate rules.
|
||
|
|
* @returns {IterableIterator<[string, Rule]>} Rules.
|
||
|
|
*/
|
||
|
|
*entries() {
|
||
|
|
for (const [ruleId, load] of super.entries()) {
|
||
|
|
yield [ruleId, load()];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Call a function with each rule.
|
||
|
|
* @param {Function} callbackFn The callback function.
|
||
|
|
* @param {any} [thisArg] The object to pass to `this` of the callback function.
|
||
|
|
* @returns {void}
|
||
|
|
*/
|
||
|
|
forEach(callbackFn, thisArg) {
|
||
|
|
for (const [ruleId, load] of super.entries()) {
|
||
|
|
callbackFn.call(thisArg, load(), ruleId, this);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// Forbid mutation.
|
||
|
|
Object.defineProperties(LazyLoadingRuleMap.prototype, {
|
||
|
|
clear: { configurable: true, value: void 0 },
|
||
|
|
delete: { configurable: true, value: void 0 },
|
||
|
|
[Symbol.iterator]: {
|
||
|
|
configurable: true,
|
||
|
|
writable: true,
|
||
|
|
value: LazyLoadingRuleMap.prototype.entries
|
||
|
|
}
|
||
|
|
});
|
||
|
|
|
||
|
|
module.exports = { LazyLoadingRuleMap };
|