1- interface IOptions {
2- strict : boolean ;
3- }
1+ import { v3 as hash } from 'murmurhash'
42
5- const makeCopy = ( jsonValue : any ) => {
6- let copyJson : any ;
3+ const EMPTY_OBJECT = '__empty__obj'
4+ const EMPTY_ARRAY = '__empty__arr'
75
8- if ( Array . isArray ( jsonValue ) ) {
9- copyJson = [ ...jsonValue ]
10- } else {
11- copyJson = { ...jsonValue }
6+ class Node {
7+ public children : any
8+ public hash : number
9+ constructor ( ) {
10+ this . children = [ ]
11+ this . hash = 0
1212 }
13-
14- return copyJson
1513}
1614
17- const atLeastSatisfySource = ( objSource : any , objDest : any , strict : boolean = false ) => {
18- let satisfied : boolean = true
19-
20- if ( typeof objSource === 'object' ) {
21- // handle json object
22- for ( const key of Object . keys ( objSource ) ) {
23- if ( strict ) {
24- satisfied = satisfied && objSource [ key ] === objDest [ key ]
25- } else {
26- // tslint:disable-next-line: triple-equals
27- satisfied = satisfied && objSource [ key ] == objDest [ key ]
28- }
29- }
30- } else {
31- // handle primitive type
32- if ( strict ) {
33- satisfied = satisfied && objSource === objDest
34- } else {
35- // tslint:disable-next-line: triple-equals
36- satisfied = satisfied && objSource == objDest
37- }
38- }
39-
40- return satisfied
15+ const hasher = ( thing : any , prefix : string = '' ) => {
16+ const stringThing = prefix + ( typeof thing ) + '::' + thing
17+ return hash ( stringThing )
4118}
4219
43- const compareObject = ( objMaster : any , objToCompare : any , opt ?: IOptions ) : boolean => {
44- let satisfied : boolean = true ;
45-
46- if ( Array . isArray ( objMaster ) ) {
47- satisfied = satisfied && compareArray ( objMaster , objToCompare , opt ) ;
48- } else {
49- satisfied = satisfied && atLeastSatisfySource ( objMaster , objToCompare , opt ?. strict )
50- }
51-
52- return satisfied ;
20+ const combineHashes = ( parentHash : any , child : any ) => {
21+ /* tslint:disable:no-bitwise */
22+ return ( parentHash + child . hash ) & 0xFFFFFFFF
5323}
5424
55- const compareArray = ( jsonArrMaster : any , jsonArrToCompare : any , opt ?: IOptions ) : boolean => {
56- const arrComparison : any = makeCopy ( jsonArrToCompare )
57- let satisfied : boolean = true ;
58- for ( const key of Object . keys ( jsonArrMaster ) ) {
59- // check key is number
60- const isKeyNumber = Number . NaN !== Number ( key )
25+ const newNode = ( thing : any , prefix : string ) => {
26+ const node = new Node ( )
27+ node . hash = hasher ( thing , prefix )
28+ return node
29+ }
6130
62- if ( isKeyNumber ) {
63- let foundSatisfy = false
64- for ( const keyOnComp of Object . keys ( arrComparison ) ) {
65- foundSatisfy = compareObject ( jsonArrMaster [ key ] , arrComparison [ keyOnComp ] )
31+ const createTree = ( currNode : Node , currentInput : any , prefix : string = '' ) => {
32+ const isObject = typeof currentInput === 'object'
33+ const isNil = currentInput === null || typeof currentInput === 'undefined'
34+ const isArray = Array . isArray ( currentInput )
35+ const keys : any = ! isNil ? Object . keys ( currentInput ) : [ ]
6636
67- if ( foundSatisfy ) {
68- foundSatisfy = true
69- delete arrComparison [ keyOnComp ]
70- break
71- }
72- }
73- satisfied = satisfied && foundSatisfy
74- } else {
75- satisfied = satisfied && compareObject ( jsonArrMaster [ key ] , arrComparison [ key ] , opt ) ;
76- delete arrComparison [ key ]
77- }
37+ // we're at a weird value
38+ if ( currentInput instanceof Date || currentInput instanceof RegExp ) {
39+ return newNode ( currentInput , prefix )
7840 }
79- return satisfied
80- }
8141
82- export const compare = ( jsonMaster : any , jsonToCompare : any , opt ?: IOptions ) : boolean => {
83- if ( ! jsonMaster || ! jsonToCompare ) return false
42+ // if we're at a value
43+ if ( ! isObject && ! isArray ) {
44+ return newNode ( currentInput , prefix )
45+ }
8446
85- if ( Array . isArray ( jsonMaster ) || Array . isArray ( jsonToCompare ) ) {
86- if ( Array . isArray ( jsonMaster ) && ! Array . isArray ( jsonToCompare ) ||
87- ! Array . isArray ( jsonMaster ) && Array . isArray ( jsonToCompare ) ) {
88- return false
47+ // if we're at an iterable
48+ if ( ! keys . length ) {
49+ return isArray ? newNode ( EMPTY_ARRAY , prefix ) : newNode ( EMPTY_OBJECT , prefix )
50+ }
51+ for ( const key of keys ) {
52+ let pfx
53+ if ( ! isArray && isObject ) { // if we're dealing with an object prefix the key
54+ pfx = key
8955 }
56+
57+ const node = createTree ( new Node ( ) , currentInput [ key ] , pfx )
58+ currNode . children . push ( node )
9059 }
60+ // iterable's hash is combined hash of all children
61+ const combined = currNode . children . reduce ( combineHashes , 0 )
62+ currNode . hash = hasher ( combined )
63+ return currNode
64+ }
9165
92- let satisfied : boolean = true ;
66+ const createFinalHash = ( input : any ) => {
67+ const tree = createTree ( new Node ( ) , input )
68+ return tree . hash
69+ }
9370
94- if ( Array . isArray ( jsonMaster ) ) {
95- satisfied = satisfied && compareArray ( jsonMaster , jsonToCompare , opt ) ;
96- } else {
97- satisfied = satisfied && compareObject ( jsonMaster , jsonToCompare , opt ) ;
71+ export const compare = ( a : any , b : any ) => {
72+ if ( a && b && ( ( Array . isArray ( a ) && Array . isArray ( b ) ) || ( typeof a === 'object' && typeof b === 'object' ) ) && ( a . length === b . length ) ) {
73+ return createFinalHash ( a ) === createFinalHash ( b )
9874 }
99-
100- return satisfied ;
101- } ;
75+ return false
76+ }
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