Prevent batch_size usage when overwrite is set to True in bulk_import

arango/collection.py

@@ -1992,12 +1992,17 @@ def import_bulk(
             IMPORTANT NOTE: this parameter may go through breaking changes
             in the future where the return type may not be a list of result
             objects anymore. Use it at your own risk, and avoid
-            depending on the return value if possible.
+            depending on the return value if possible. Cannot be used with
+            parameter **overwrite**.
         :type batch_size: int
         :return: Result of the bulk import.
         :rtype: dict | list[dict]
         :raise arango.exceptions.DocumentInsertError: If import fails.
         """
+        if overwrite and batch_size is not None:
+            msg = "Cannot use parameter 'batch_size' if 'overwrite' is set to True"
+            raise ValueError(msg)
+
         documents = [self._ensure_key_from_id(doc) for doc in documents]
 
         params: Params = {"type": "array", "collection": self.name}

tests/test_document.py

@@ -1843,6 +1843,10 @@ def test_document_import_bulk(col, bad_col, docs):
     assert len(result) == 1
     empty_collection(col)
 
+    # Test import bulk with overwrite and batch_size
+    with pytest.raises(ValueError):
+        col.import_bulk(docs, overwrite=True, batch_size=1)
+
     # Test import bulk on_duplicate actions
     doc = docs[0]
     doc_key = doc["_key"]