tools: consolidate update-authors.js logic

Use a single regex and fewer logical branches in the code.
PR-URL: #41255
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Mohammed Keyvanzadeh <mohammadkeyvanzade94@gmail.com>

Author: Trott

tools/update-authors.js

@@ -39,25 +39,13 @@ const mailmap = new CaseIndifferentMap();
 line=line.trim();
 if(line.startsWith('#')||line==='')continue;
 
-letmatch;
-// Replaced Name <original@example.com>
-if(match=line.match(/^([^<]+)\s+(<[^>]+>)$/)){
-mailmap.set(match[2].toLowerCase(),{
-author: match[1],email: match[2]
-});
-// <replaced@example.com> <original@example.com>
-}elseif(match=line.match(/^<([^>]+)>\s+(<[^>]+>)$/)){
-mailmap.set(match[2].toLowerCase(),{email: match[1]});
-// Replaced Name <replaced@example.com> <original@example.com>
-}elseif(match=line.match(/^([^<]+)\s+(<[^>]+>)\s+(<[^>]+>)$/)){
-mailmap.set(match[3].toLowerCase(),{
-author: match[1],email: match[2]
-});
-// Replaced Name <replaced@example.com> Original Name <original@example.com>
-}elseif(match=
-line.match(/^([^<]+)\s+(<[^>]+>)\s+([^<]+)\s+(<[^>]+>)$/)){
-mailmap.set(match[3]+'\0'+match[4].toLowerCase(),{
-author: match[1],email: match[2]
+constmatch=line.match(/^(?:([^<]+)\s+)?(?:(<[^>]+>)\s+)?(?:([^<]+)\s+)?(<[^>]+>)$/);
+if(match){
+const[,replaceName,replaceEmail,originalName,originalEmail]=match;
+constkey=originalName ? `${originalName}\0${originalEmail.toLocaleLowerCase()}` : originalEmail.toLowerCase();
+mailmap.set(key,{
+author: replaceName||originalName,
+email: replaceEmail||originalEmail,
 });
 }else{
 console.warn('Unknown .mailmap format:',line);
@@ -73,8 +61,8 @@ const previousAuthors = new CaseIndifferentMap();
 line=line.trim();
 if(line.startsWith('#')||line==='')continue;
 
-letmatch;
-if(match=line.match(/^([^<]+)\s+(<[^>]+>)$/)){
+constmatch=line.match(/^([^<]+)\s+(<[^>]+>)$/);
+if(match){
 constname=match[1];
 constemail=match[2];
 if(previousAuthors.has(name)){