From 89d83adb43c8b15de072c8c52e62145fd69abfd7 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Wed, 15 Apr 2026 11:28:29 +0000
Subject: [PATCH] fix: skip headline overwrite when content already has
 headline
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ドラフトPRのbodyからヘッドラインを埋め込む処理で、すでにファイル側に
ヘッドラインが書かれている場合は上書きしないようにする。

Co-authored-by: azu <azu@users.noreply.github.com>
---
 actions/update-draft-pr/src/rename.ts | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/actions/update-draft-pr/src/rename.ts b/actions/update-draft-pr/src/rename.ts
index cc627dfa519..d36e081d6e9 100644
--- a/actions/update-draft-pr/src/rename.ts
+++ b/actions/update-draft-pr/src/rename.ts
@@ -20,11 +20,25 @@ interface EmbedHeadlineParams {
     headline?: string;
 }
 
+const HEADLINE_SECTION_PATTERN = /---\s+JSer\.info #\d+(?:\s+-\s+)?\s*([\s\S]*?)\s*----/;
+
+const hasExistingHeadline = (content: string): boolean => {
+    const match = content.match(HEADLINE_SECTION_PATTERN);
+    if (!match) {
+        return false;
+    }
+    return match[1].trim().length > 0;
+};
+
 const embedHeadline = ({ content, headline }: EmbedHeadlineParams): string => {
     if (!headline) {
         console.log("headline is not defined");
         return content;
     }
+    if (hasExistingHeadline(content)) {
+        console.log("headline is already written in content; skip overwrite");
+        return content;
+    }
     console.log("# headline")
     console.log(headline);
     console.log("# content")