assert,util: improve array comparison

Sparse arrays and arrays containing undefined are now compared faster
using assert.deepStrictEqual() or util.isDeepStrictEqual().
PR-URL: #57619
Reviewed-By: Jordan Harband <ljharb@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Edy Silva <edigleyssonsilva@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Rafael Gonzaga <rafael.nunu@hotmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>

Author: BridgeAR

benchmark/assert/deepequal-simple-array-and-set.js

@@ -11,6 +11,8 @@ const bench = common.createBenchmark(main, {
 method: [
 'deepEqual_Array',
 'notDeepEqual_Array',
+'deepEqual_sparseArray',
+'notDeepEqual_sparseArray',
 'deepEqual_Set',
 'notDeepEqual_Set',
 ],
@@ -25,18 +27,30 @@ function run(fn, n, actual, expected) {
 }
 
 functionmain({ n, len, method, strict }){
-constactual=[];
-constexpected=[];
+letactual=Array.from({length: len},(_,i)=>i);
+// Contain one undefined value to trigger a specific code path
+actual[0]=undefined;
+letexpected=actual.slice(0);
 
-for(leti=0;i<len;i++){
-actual.push(i);
-expected.push(i);
-}
 if(method.includes('not')){
 expected[len-1]+=1;
 }
 
 switch(method){
+case'deepEqual_sparseArray':
+case'notDeepEqual_sparseArray':
+actual=newArray(len);
+for(leti=0;i<len;i+=2){
+actual[i]=i;
+}
+expected=actual.slice(0);
+if(method.includes('not')){
+expected[len-2]+=1;
+run(strict ? notDeepStrictEqual : notDeepEqual,n,actual,expected);
+}else{
+run(strict ? deepStrictEqual : deepEqual,n,actual,expected);
+}
+break;
 case'deepEqual_Array':
 run(strict ? deepStrictEqual : deepEqual,n,actual,expected);
 break;

lib/internal/assert/myers_diff.js

@@ -29,6 +29,7 @@ function myersDiff(actual, expected, checkCommaDisparity = false) {
 constactualLength=actual.length;
 constexpectedLength=expected.length;
 constmax=actualLength+expectedLength;
+// TODO(BridgeAR): Cap the input in case the values go beyond the limit of 2^31 - 1.
 constv=newInt32Array(2*max+1);
 consttrace=[];
 

lib/internal/util/comparisons.js

@@ -196,11 +196,9 @@ function innerDeepEqual(val1, val2, mode, memos) {
 }
 }else{
 if(val1===null||typeofval1!=='object'){
-if(val2===null||typeofval2!=='object'){
-// eslint-disable-next-line eqeqeq
-returnval1==val2||(NumberIsNaN(val1)&&NumberIsNaN(val2));
-}
-returnfalse;
+return(val2===null||typeofval2!=='object')&&
+// eslint-disable-next-line eqeqeq
+(val1==val2||(NumberIsNaN(val1)&&NumberIsNaN(val2)));
 }
 if(val2===null||typeofval2!=='object'){
 returnfalse;
@@ -384,9 +382,7 @@ function keyCheck(val1, val2, mode, memos, iterationType, keys2) {
 }
 }elseif(keys2.length!==ObjectKeys(val1).length){
 returnfalse;
-}
-
-if(mode===kStrict){
+}elseif(mode===kStrict){
 constsymbolKeysA=getOwnSymbols(val1);
 if(symbolKeysA.length!==0){
 letcount=0;
@@ -761,9 +757,9 @@ function sparseArrayEquiv(a, b, mode, memos, i) {
 if(keysA.length!==keysB.length){
 returnfalse;
 }
-for(;i<keysA.length;i++){
-constkey=keysA[i];
-if(!hasOwn(b,key)||!innerDeepEqual(a[key],b[key],mode,memos)){
+for(;i<keysB.length;i++){
+constkey=keysB[i];
+if((a[key]===undefined&&!hasOwn(a,key))||!innerDeepEqual(a[key],b[key],mode,memos)){
 returnfalse;
 }
 }
@@ -785,17 +781,14 @@ function objEquiv(a, b, mode, keys2, memos, iterationType) {
 returnpartialArrayEquiv(a,b,mode,memos);
 }
 for(leti=0;i<a.length;i++){
-if(!innerDeepEqual(a[i],b[i],mode,memos)){
-returnfalse;
-}
-constisSparseA=a[i]===undefined&&!hasOwn(a,i);
-constisSparseB=b[i]===undefined&&!hasOwn(b,i);
-if(isSparseA!==isSparseB){
+if(b[i]===undefined){
+if(!hasOwn(b,i))
+returnsparseArrayEquiv(a,b,mode,memos,i);
+if(a[i]!==undefined||!hasOwn(a,i))
+returnfalse;
+}elseif(a[i]===undefined||!innerDeepEqual(a[i],b[i],mode,memos)){
 returnfalse;
 }
-if(isSparseA){
-returnsparseArrayEquiv(a,b,mode,memos,i);
-}
 }
 }elseif(iterationType===kIsSet){
 if(!setEquiv(a,b,mode,memos)){