From 9fa0bbc834ba4a95a946e033b31bdb01e0101573 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Thu, 30 Jul 2026 14:51:50 +0000
Subject: [PATCH] perf: optimize seo-audit.mjs with parallel async file reading

Refactors the main file reading loop in `seo-audit.mjs` to use `readFile`
from `node:fs/promises` and `Promise.all` instead of the synchronous
`readFileSync`. This parallelizes disk I/O when processing large numbers
of generated HTML files.

Co-authored-by: lsb11 <269203137+lsb11@users.noreply.github.com>
---
 .gitignore    | 1 +
 seo-audit.mjs | 7 ++++---
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/.gitignore b/.gitignore
index 75f4737..88b54aa 100644
--- a/.gitignore
+++ b/.gitignore
@@ -45,3 +45,4 @@ gsc-coverage-report.csv
 .seo-fix-backup-path
 
 service_account.json
+dist_large/
diff --git a/seo-audit.mjs b/seo-audit.mjs
index 5daacec..1f94fc3 100644
--- a/seo-audit.mjs
+++ b/seo-audit.mjs
@@ -2,6 +2,7 @@
 // seo-audit.mjs — machine-check every built page in dist/.
 // Run after `npm run build`. Exits 1 if any ERROR found (CI-safe).
 import { readdirSync, readFileSync, existsSync, statSync } from 'node:fs';
+import { readFile } from 'node:fs/promises';
 import { join } from 'node:path';
 
 const DIST = 'dist';
@@ -68,9 +69,9 @@ const titles = new Map();
 const descs = new Map();
 const NOINDEX_OK = [/^\/404(\.html)?\/?$/, /^\/sitemap-page\/$/, /^\/embed\//];
 
-for (const f of htmlFiles) {
+await Promise.all(htmlFiles.map(async (f) => {
   const page = f.slice(DIST.length).replace(/index\.html$/, '') || '/';
-  const html = readFileSync(f, 'utf8');
+  const html = await readFile(f, 'utf8');
   const isNoindexOk = NOINDEX_OK.some((r) => r.test(page)) || page === '/404.html/';
 
   // canonical
@@ -132,7 +133,7 @@ for (const f of htmlFiles) {
     else if (r === 'needs-slash') warn(`${page} — link ${h} missing trailing slash (301 hop)`);
     else if (r === 'redirect' && !h.startsWith('/go/')) warn(`${page} — link ${h} goes through a 301 (point it at the target directly)`);
   }
-}
+}));
 
 // duplicates
 for (const [t, pages] of titles) if (pages.length > 1) warn(`DUPLICATE TITLE on ${pages.join(' , ')} :: "${t.slice(0, 70)}"`);