updeep-remeda/lib/freeze.js
2018-02-19 18:01:31 -08:00

57 lines
1.2 KiB
JavaScript

function isFreezable(object) {
if (object === null) return false
if (object instanceof RegExp) return false
if (object instanceof ArrayBuffer) return false
return Array.isArray(object) || typeof object === 'object'
}
function needsFreezing(object) {
return isFreezable(object) && !Object.isFrozen(object)
}
function recur(object) {
Object.freeze(object)
Object.keys(object).forEach(key => {
const value = object[key]
if (needsFreezing(value)) {
recur(value)
}
})
return object
}
/**
* Deeply freeze a plain javascript object.
*
* If `process.env.NODE_ENV === 'production'`, this returns the original object
* without freezing.
*
* Or if `process.env.UPDEEP_MODE === 'dangerously_never_freeze'`, this returns the original object
* without freezing.
*
* @function
* @sig a -> a
* @param {object} object Object to freeze.
* @return {object} Frozen object, unless in production, then the same object.
*/
function freeze(object) {
if (process.env.NODE_ENV === 'production') {
return object
}
if (process.env.UPDEEP_MODE === 'dangerously_never_freeze') {
return object
}
if (needsFreezing(object)) {
recur(object)
}
return object
}
export default freeze