fix: get diffs properly

mcp/checkout.ts

@@ -27,6 +27,28 @@ export type DiffFile = {
   patch?: string | undefined;
 };
 
+/**
+ * Parse raw `git diff` output into per-file DiffFile objects.
+ * Used as a fallback when the Gitea API doesn't return patch data.
+ */
+export function parseDiffToFiles(rawDiff: string): DiffFile[] {
+  const files: DiffFile[] = [];
+  const parts = rawDiff.split(/^(?=diff --git )/m);
+  for (const part of parts) {
+    if (!part.trim()) continue;
+    const headerMatch = part.match(/^diff --git a\/.+ b\/(.+)\n/);
+    if (!headerMatch) continue;
+    const filename = headerMatch[1].trim();
+    const patchStart = part.indexOf("\n@@");
+    if (patchStart === -1) {
+      files.push({ filename });
+    } else {
+      files.push({ filename, patch: part.slice(patchStart + 1) });
+    }
+  }
+  return files;
+}
+
 export function formatFilesWithLineNumbers(files: DiffFile[]): FormatFilesResult {
   const output: string[] = [];
   const tocEntries: Array<{ filename: string; startLine: number; endLine: number }> = [];
@@ -136,14 +158,13 @@ export async function fetchAndFormatPrDiff(
   ctx: ToolContext,
   pullNumber: number
 ): Promise<FetchAndFormatPrDiffResult> {
-  const r = await ctx.gitea.request(
-    "GET /repos/{owner}/{repo}/pulls/{index}/files",
-    { owner: ctx.repo.owner, repo: ctx.repo.name, index: pullNumber, limit: 50 }
-  );
-  const files: DiffFile[] = (r.data as Array<{ filename?: string; patch?: string }>).map((f) => ({
-    filename: f.filename,
-    patch: f.patch,
-  }));
+  const r = await ctx.gitea.rest.repository.repoDownloadPullDiffOrPatch({
+    owner: ctx.repo.owner,
+    repo: ctx.repo.name,
+    index: pullNumber,
+    diffType: "diff",
+  });
+  const files = parseDiffToFiles(r.data);
   return { ...formatFilesWithLineNumbers(files), files };
 }