tools: implement update-authors in JS

Replace the previous Perl script with a Node.js variant
that explicitly supports `Author:` and, in particular,
GitHub’s standard `Co-authored-by:` metadata tags.
PR-URL: #22771
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Matheus Marchini <mat@mmarchini.me>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: addaleax

tools/update-authors.js

@@ -0,0 +1,50 @@
+#!/usr/bin/env node
+// Usage: tools/update-author.js [--dry]
+// Passing --dry will redirect output to stdout rather than write to 'AUTHORS'.
+'use strict';
+const{ spawn }=require('child_process');
+constfs=require('fs');
+constreadline=require('readline');
+
+constlog=spawn(
+'git',
+// Inspect author name/email and body.
+['log','--reverse','--format=Author: %aN <%aE>\n%b'],{
+stdio: ['inherit','pipe','inherit']
+});
+constrl=readline.createInterface({input: log.stdout});
+
+letoutput;
+if(process.argv.includes('--dry'))
+output=process.stdout;
+else
+output=fs.createWriteStream('AUTHORS');
+
+output.write('# Authors ordered by first contribution.\n\n');
+
+constseen=newSet();
+
+// Support regular git author metadata, as well as `Author:` and
+// `Co-authored-by:` in the message body. Both have been used in the past
+// to indicate multiple authors per commit, with the latter standardized
+// by GitHub now.
+constauthorRe=
+/(^Author:|^Co-authored-by:)\s+(?<author>[^<]+)\s+(?<email><[^>]+>)/i;
+rl.on('line',(line)=>{
+constmatch=line.match(authorRe);
+if(!match)return;
+
+const{ author, email }=match.groups;
+if(seen.has(email)||
+/@chromium\.org/.test(email)||
+email==='<erik.corry@gmail.com>'){
+return;
+}
+
+seen.add(email);
+output.write(`${author}${email}\n`);
+});
+
+rl.on('close',()=>{
+output.end('\n# Generated by tools/update-authors.js\n');
+});