path: simplify normalizeString

This improves the `path.normalize()` and `path.resolve()` performance a tiny bit. One statement could never be truthy, another check could be simplified and `code` is now monomorphic. PR-URL: #27240 Reviewed-By: Yongsheng Zhang <[email protected]> Reviewed-By: Luigi Pinca <[email protected]>

Author: BridgeAR

lib/path.js

@@ -50,11 +50,11 @@ function isWindowsDeviceRoot(code){
 
 // Resolves . and .. elements in a path with directory names
 functionnormalizeString(path,allowAboveRoot,separator,isPathSeparator){
-varres='';
-varlastSegmentLength=0;
-varlastSlash=-1;
-vardots=0;
-varcode;
+letres='';
+letlastSegmentLength=0;
+letlastSlash=-1;
+letdots=0;
+letcode=0;
 for(vari=0;i<=path.length;++i){
 if(i<path.length)
 code=path.charCodeAt(i);
@@ -66,7 +66,7 @@ function normalizeString(path, allowAboveRoot, separator, isPathSeparator){
 if(isPathSeparator(code)){
 if(lastSlash===i-1||dots===1){
 // NOOP
-}elseif(lastSlash!==i-1&&dots===2){
+}elseif(dots===2){
 if(res.length<2||lastSegmentLength!==2||
 res.charCodeAt(res.length-1)!==CHAR_DOT||
 res.charCodeAt(res.length-2)!==CHAR_DOT){
@@ -82,7 +82,7 @@ function normalizeString(path, allowAboveRoot, separator, isPathSeparator){
 lastSlash=i;
 dots=0;
 continue;
-}elseif(res.length===2||res.length===1){
+}elseif(res.length!==0){
 res='';
 lastSegmentLength=0;
 lastSlash=i;