Add graph_exists check to repo_info endpoints, fix test cleanup assertion

- Replace ineffective 'if stats is None' guard in repo_info with
  g.graph_exists() check in both api/index.py and tests/index.py
- Add missing mock_db.aclose assertion in test_async_get_repos_empty

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: gkorland

api/index.py

@@ -178,12 +178,15 @@ async def repo_info(data: RepoRequest, _=Depends(public_or_auth)):
 
     g = AsyncGraphQuery(data.repo)
     try:
+        if not await g.graph_exists():
+            return JSONResponse({"status": f'Missing repository "{data.repo}"'}, status_code=400)
+
         stats = await g.stats()
     finally:
         await g.close()
     info = await async_get_repo_info(data.repo)
 
-    if stats is None or info is None:
+    if info is None:
         return JSONResponse({"status": f'Missing repository "{data.repo}"'}, status_code=400)
 
     stats |= info

tests/index.py

@@ -142,11 +142,14 @@ async def list_repos(_=Depends(token_required)):
     async def repo_info(data: RepoRequest, _=Depends(token_required)):
         g = AsyncGraphQuery(data.repo)
         try:
+            if not await g.graph_exists():
+                return JSONResponse({"status": f'Missing repository "{data.repo}"'}, status_code=400)
+
             stats = await g.stats()
         finally:
             await g.close()
         info = await async_get_repo_info(data.repo)
-        if stats is None or info is None:
+        if info is None:
             return JSONResponse({"status": f'Missing repository "{data.repo}"'}, status_code=400)
         stats |= info
         return {"status": "success", "info": stats}

tests/test_async_graph.py

@@ -82,6 +82,7 @@ async def test_async_get_repos_empty():
         repos = await async_get_repos()
 
     assert repos == []
+    mock_db.aclose.assert_awaited_once()
 
 
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