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// @ts-check
const {isDeepStrictEqual} = require('util')
/**
* ObjectMap extends Map, but determines key equality using Node.js’ `util.isDeepStrictEqual` rather than using [SameValueZero](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map#key_equality). This makes using objects as keys a bit simpler.
*/
module.exports = class ObjectMap extends Map {
#data
constructor(iterable = []) {
super()
this.#data = iterable
}
clear() {
this.#data = []
}
delete(key) {
if (!this.has(key)) {
return false
}
this.#data = this.#data.filter(([existingKey]) => !isDeepStrictEqual(existingKey, key))
return true
}
entries() {
return this.#data[Symbol.iterator]()
}
forEach(cb) {
for (const [key, value] of this.#data) {
cb(value, key, this.#data)
}
}
get(key) {
return this.#data.find(([existingKey]) => isDeepStrictEqual(existingKey, key))?.[1]
}
has(key) {
return this.#data.findIndex(([existingKey]) => isDeepStrictEqual(existingKey, key)) !== -1
}
keys() {
return this.#data.map(([key]) => key)[Symbol.iterator]()
}
set(key, value) {
this.delete(key)
this.#data.push([key, value])
return this
}
values() {
return this.#data.map(([, value]) => value)[Symbol.iterator]()
}
}