index.ts
1.07 KB
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
export function shallowEqual<T>(
objA: T,
objB: T,
compare?: (a: T, b: T, key?: string) => boolean | void,
compareContext?: any,
) {
let compareResult = compare
? compare.call(compareContext, objA, objB)
: void 0
if (compareResult !== void 0) {
return !!compareResult
}
if (objA === objB) {
return true
}
if (typeof objA !== 'object' || !objA || typeof objB !== 'object' || !objB) {
return false
}
const keysA = Object.keys(objA)
const keysB = Object.keys(objB)
if (keysA.length !== keysB.length) {
return false
}
const bHasOwnProperty = Object.prototype.hasOwnProperty.bind(objB)
// Test for A's keys different from B.
for (let idx = 0; idx < keysA.length; idx++) {
const key = keysA[idx] as string
if (!bHasOwnProperty(key)) {
return false
}
const valueA = (objA as any)[key]
const valueB = (objB as any)[key]
compareResult = compare
? compare.call(compareContext, valueA, valueB, key)
: void 0
if (
compareResult === false ||
(compareResult === void 0 && valueA !== valueB)
) {
return false
}
}
return true
}