fix: prevent hooks.server code being imported into client during build (#12195)

* fix hooks.server matching hooks

* changeset

* unit test

* Update .changeset/slimy-eyes-pull.md

---------

Co-authored-by: Tee Ming <[email protected]>

Author: CaptainCodeman

.changeset/slimy-eyes-pull.md

@@ -0,0 +1,5 @@
+---
+"@sveltejs/kit": patch
+---
+
+fix: prevent client import error when a `hooks.server` file imports a private environment variable

packages/kit/src/utils/filesystem.js

@@ -181,7 +181,7 @@ export function resolve_entry(entry) {
 			const base = path.basename(entry);
 			const files = fs.readdirSync(dir);
 
-			const found = files.find((file) => file.replace(/\.[^.]+$/, '') === base);
+			const found = files.find((file) => file.replace(/\.(js|ts)$/, '') === base);
 
 			if (found) return path.join(dir, found);
 		}

packages/kit/src/utils/filesystem.spec.js

@@ -2,7 +2,7 @@ import { mkdtempSync, writeFileSync, readdirSync, mkdirSync, readFileSync } from
 import { tmpdir } from 'node:os';
 import { dirname, join } from 'node:path';
 import { assert, expect, beforeEach, test } from 'vitest';
-import { copy, mkdirp } from './filesystem.js';
+import { copy, mkdirp, resolve_entry } from './filesystem.js';
 
 /** @type {string} */
 let source_dir;
@@ -99,3 +99,9 @@ test('replaces strings', () => {
 		'the quick brown fox jumps over the lazy dog'
 	);
 });
+
+test('ignores hooks.server folder when resolving hooks', () => {
+	write('hooks.server/index.js', '');
+
+	expect(resolve_entry(source_dir + '/hooks')).null;
+});