fix empty mind map issue (infiniflow#1991)

### What problem does this PR solve? ### Type of change - [x] Bug Fix (non-breaking change which fixes an issue)
ckldy · Aug 19, 2024 · 2302a6b · 2302a6b
1 parent a74c0cc
commit 2302a6b
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/graphrag/mind_map_extractor.py b/graphrag/mind_map_extractor.py
@@ -105,6 +105,9 @@ def __call__(
             for i, _ in enumerate(threads):
                 res.append(_.result())
 
+            if not res:
+                return MindMapResult(output={"root":{}})
+
             merge_json = reduce(self._merge, res)
             if len(merge_json.keys()) > 1:
                 keyset = set(