-
Notifications
You must be signed in to change notification settings - Fork 0
/
fixd.js
70 lines (68 loc) · 2.19 KB
/
fixd.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
'use strict'
const clone = require('lodash.clonedeep')
const fixd = {
/**
* Deeply freezes an object
* @param {*} obj The object to freeze
* @returns {*}
*/
freeze: (obj) => {
Object.freeze(obj)
/* istanbul ignore else */
if (obj) {
Object.getOwnPropertyNames(obj).forEach((prop) => {
if (obj.hasOwnProperty(prop) &&
obj[prop] !== null &&
(typeof obj[prop] === 'object' || typeof obj[prop] === 'function') &&
!Object.isFrozen(obj[prop])) {
fixd.freeze(obj[prop])
}
})
}
return obj
},
/**
* Retrieves a value from the fixd library
* @param {Object} target Target object to retrieve from
* @param {String} name Property name to retrieve
* @returns {*} The value of the property
*/
get: (target, name) => {
if (typeof name === 'symbol') return target
if (['freeze', 'get', 'set', 'create'].includes(name)) return target[name]
if (!fixd[name] || !fixd[name].$fixdVal) throw new Error(`Namespace '${name}' does not exist`)
return fixd[name].$fixdVal
},
/**
* Add a property to the fixd library and freezes if not in namespace
* @param {Object} obj The object to set
* @param {String} prop A string name to represent the fixture
* @param {*} value The value to set
* @returns {Boolean}
*/
set: (obj, prop, value) => {
if (fixd[prop]) {
throw new Error(`Cannot add fixture to already reserved namespace '${prop}'.`)
}
fixd[prop] = fixd.freeze({ $fixdVal: clone(value) })
return true
},
/**
* Returns a fixture and allows for (option) modification
* @param {String} name The namespace of the fixture to mutate
* @param {Function} modifier A function to modify the fixture
* @returns {*} Unreferenced, immutable copy of object
*/
create: (name, modifier) => {
if (typeof modifier !== 'function') {
throw new Error('Modifier must be a function')
}
if (!fixd[name]) {
throw new Error(`Namespace '${name}' does not exist`)
}
const newObj = modifier(clone(fixd[name].$fixdVal))
if (newObj) return fixd.freeze(newObj)
throw new Error('Modifier should return a value')
}
}
module.exports = new Proxy(fixd, fixd)