From 37e80730eced938dbd75241d2d1b8184be583e83 Mon Sep 17 00:00:00 2001
From: silverwind <me@silverwind.io>
Date: Fri, 24 Jul 2026 21:25:38 +0200
Subject: [PATCH] fix: abort superseded issue suggestion requests (#38620)

Fix regression from https://github.com/go-gitea/gitea/pull/38610

`perfect-debounce` allowed only one request in flight; `debounce` does
not, so a slow older request can resolve after a newer one and leave a
stale suggestion menu. Superseded requests are now aborted.
---
 web_src/js/features/comp/TextExpander.ts | 21 +++++++++++++++------
 web_src/js/utils/match.ts                |  4 ++--
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/web_src/js/features/comp/TextExpander.ts b/web_src/js/features/comp/TextExpander.ts
index a01598086e..2eb79fc8ec 100644
--- a/web_src/js/features/comp/TextExpander.ts
+++ b/web_src/js/features/comp/TextExpander.ts
@@ -4,11 +4,12 @@ import {svg} from '../../svg.ts';
 import {parseIssueHref, parseRepoOwnerPathInfo} from '../../utils.ts';
 import {createElementFromAttrs, createElementFromHTML} from '../../utils/dom.ts';
 import {getIssueColorClass, getIssueIcon} from '../issue.ts';
+import {errorName} from '../../modules/errors.ts';
 import {debounce} from '../../utils/func.ts';
 import type TextExpanderElement from '@github/text-expander-element';
 import type {TextExpanderChangeEvent, TextExpanderResult} from '@github/text-expander-element';
 
-async function fetchIssueSuggestions(key: string, text: string): Promise<TextExpanderResult> {
+async function fetchIssueSuggestions(key: string, text: string, signal: AbortSignal): Promise<TextExpanderResult> {
   const issuePathInfo = parseIssueHref(window.location.href);
   if (!issuePathInfo.ownerName) {
     const repoOwnerPathInfo = parseRepoOwnerPathInfo(window.location.pathname);
@@ -18,7 +19,7 @@ async function fetchIssueSuggestions(key: string, text: string): Promise<TextExp
   }
   if (!issuePathInfo.ownerName) return {matched: false};
 
-  const matches = await matchIssue(issuePathInfo.ownerName, issuePathInfo.repoName, issuePathInfo.indexString, text);
+  const matches = await matchIssue(issuePathInfo.ownerName, issuePathInfo.repoName, issuePathInfo.indexString, text, signal);
   if (!matches.length) return {matched: false};
 
   const ul = createElementFromAttrs('ul', {class: 'suggestions'});
@@ -48,6 +49,7 @@ export function initTextExpander(expander: TextExpanderElement) {
     return keyStart > lineStart;
   };
 
+  let suggestionsController = new AbortController();
   const debouncedIssueSuggestions = debounce(async (key: string, text: string): Promise<TextExpanderResult> => {
     // https://github.com/github/text-expander-element/issues/71
     // Upstream bug: when using "multiword+promise", TextExpander will get wrong "key" position.
@@ -58,10 +60,17 @@ export function initTextExpander(expander: TextExpanderElement) {
     // check the input before the request, to avoid emitting empty query to backend (still related to the upstream bug)
     if (!shouldShowIssueSuggestions()) return {matched: false};
     // await sleep(Math.random() * 1000); // help to reproduce the text-expander bug
-    const ret = await fetchIssueSuggestions(key, text);
-    // check the input again to avoid text-expander using incorrect position (upstream bug)
-    if (!shouldShowIssueSuggestions()) return {matched: false};
-    return ret;
+    suggestionsController.abort(); // only the newest request may answer
+    suggestionsController = new AbortController();
+    try {
+      const ret = await fetchIssueSuggestions(key, text, suggestionsController.signal);
+      // check the input again to avoid text-expander using incorrect position (upstream bug)
+      if (!shouldShowIssueSuggestions()) return {matched: false};
+      return ret;
+    } catch (err) {
+      if (errorName(err) !== 'AbortError') throw err;
+      return {matched: false};
+    }
   }, 300); // to match onInputDebounce delay
 
   expander.addEventListener('text-expander-change', (e: TextExpanderChangeEvent) => {
diff --git a/web_src/js/utils/match.ts b/web_src/js/utils/match.ts
index ac8ff16c56..6d25f3d141 100644
--- a/web_src/js/utils/match.ts
+++ b/web_src/js/utils/match.ts
@@ -71,8 +71,8 @@ export async function matchMention(mentionsUrl: string, queryText: string): Prom
   return sortAndReduce(results);
 }
 
-export async function matchIssue(owner: string, repo: string, issueIndexStr: string, query: string): Promise<Issue[]> {
-  const res = await GET(`${window.config.appSubUrl}/${owner}/${repo}/issues/suggestions?q=${encodeURIComponent(query)}`);
+export async function matchIssue(owner: string, repo: string, issueIndexStr: string, query: string, signal: AbortSignal): Promise<Issue[]> {
+  const res = await GET(`${window.config.appSubUrl}/${owner}/${repo}/issues/suggestions?q=${encodeURIComponent(query)}`, {signal});
 
   const issues: Issue[] = await res.json();
   const issueNumber = parseInt(issueIndexStr);