Ignore line anchor links with leading zeroes (#21728) (#21776)

Backport #21728
Fixes: https://github.com/go-gitea/gitea/issues/21722

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

web_src/js/features/repo-code.js

@@ -4,6 +4,9 @@ import {invertFileFolding} from './file-fold.js';
 import {createTippy} from '../modules/tippy.js';
 import {copyToClipboard} from './clipboard.js';
 
+export const singleAnchorRegex = /^#(L|n)([1-9][0-9]*)$/;
+export const rangeAnchorRegex = /^#(L[1-9][0-9]*)-(L[1-9][0-9]*)$/;
+
 function changeHash(hash) {
   if (window.history.pushState) {
     window.history.pushState(null, null, hash);
@@ -135,7 +138,7 @@ export function initRepoCodeView() {
     });
 
     $(window).on('hashchange', () => {
-      let m = window.location.hash.match(/^#(L\d+)-(L\d+)$/);
+      let m = window.location.hash.match(rangeAnchorRegex);
       let $list;
       if ($('div.blame').length) {
         $list = $('.code-view td.lines-code.blame-code');
@@ -145,6 +148,7 @@ export function initRepoCodeView() {
       let $first;
       if (m) {
         $first = $list.filter(`[rel=${m[1]}]`);
+        if ($first.length) {
           selectRange($list, $first, $list.filter(`[rel=${m[2]}]`));
 
           // show code view menu marker (don't show in blame page)
@@ -155,9 +159,11 @@ export function initRepoCodeView() {
           $('html, body').scrollTop($first.offset().top - 200);
           return;
         }
-      m = window.location.hash.match(/^#(L|n)(\d+)$/);
+      }
+      m = window.location.hash.match(singleAnchorRegex);
       if (m) {
         $first = $list.filter(`[rel=L${m[2]}]`);
+        if ($first.length) {
           selectRange($list, $first);
 
           // show code view menu marker (don't show in blame page)
@@ -167,6 +173,7 @@ export function initRepoCodeView() {
 
           $('html, body').scrollTop($first.offset().top - 200);
         }
+      }
     }).trigger('hashchange');
   }
   $(document).on('click', '.fold-file', ({currentTarget}) => {

web_src/js/features/repo-code.test.js

@@ -0,0 +1,18 @@
+import {test, expect} from 'vitest';
+import {singleAnchorRegex, rangeAnchorRegex} from './repo-code.js';
+
+test('singleAnchorRegex', () => {
+  expect(singleAnchorRegex.test('#L0')).toEqual(false);
+  expect(singleAnchorRegex.test('#L1')).toEqual(true);
+  expect(singleAnchorRegex.test('#L01')).toEqual(false);
+  expect(singleAnchorRegex.test('#n0')).toEqual(false);
+  expect(singleAnchorRegex.test('#n1')).toEqual(true);
+  expect(singleAnchorRegex.test('#n01')).toEqual(false);
+});
+
+test('rangeAnchorRegex', () => {
+  expect(rangeAnchorRegex.test('#L0-L10')).toEqual(false);
+  expect(rangeAnchorRegex.test('#L1-L10')).toEqual(true);
+  expect(rangeAnchorRegex.test('#L01-L10')).toEqual(false);
+  expect(rangeAnchorRegex.test('#L1-L01')).toEqual(false);
+});