Treat null set fields as empty in DatasetEntry.from_dict

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: J03D03

tests/test_dataset_entry.py

@@ -158,6 +158,20 @@ def test_lists_converted_to_sets(self):
         assert isinstance(e.cve_ids, set)
         assert isinstance(e.files_changed, set)
 
+    def test_null_set_fields_treated_as_empty(self):
+        data = {
+            "project_url": "https://github.com/owner/repo",
+            "commit_id": "abcdef12345",
+            "src_datasets": ["ds"],
+            "cve_ids": None,
+            "cwe_ids": None,
+            "files_changed": None,
+        }
+        e = DatasetEntry.from_dict(data)
+        assert e.cve_ids == set()
+        assert e.cwe_ids == set()
+        assert e.files_changed == set()
+
     def test_owasp_categories_converted_to_owasp_category_set(self):
         data = {
             "project_url": "https://github.com/owner/repo",

vfc_datasets/dataset_entry.py

@@ -105,7 +105,7 @@ def from_dict(cls, data: dict[str, Any]) -> Self:
         """Create a DatasetEntry from a serialized dict (e.g. loaded from JSON)."""
         set_fields = {"src_datasets", "cve_ids", "cwe_ids", "files_changed"}
         converted: dict[str, Any] = {
-            k: set(v) if k in set_fields and isinstance(v, list) else v
+            k: set(v or []) if k in set_fields else v
             for k, v in data.items()
         }
         if converted.get("owasp_categories") is not None: