Merge c524dd41e0 into 460f8d2cc8

fastapi/dependencies/utils.py

@@ -937,7 +937,10 @@ async def _extract_form_body(
             assert isinstance(value, sequence_types)
             results: list[bytes | str] = []
             for sub_value in value:
-                results.append(await sub_value.read())
+                if isinstance(sub_value, UploadFile):
+                    results.append(await sub_value.read())
+                else:
+                    results.append(sub_value)
             value = serialize_sequence_value(field=field, value=results)
         if value is not None:
             values[get_validation_alias(field)] = value

tests/test_optional_file_list.py

@@ -26,3 +26,13 @@ def test_optional_bytes_list_no_files():
     response = client.post("/files")
     assert response.status_code == 200
     assert response.json() == {"files_count": 0}
+
+
+def test_optional_bytes_list_send_empty_str():
+    client = TestClient(app)
+    response = client.post(
+        "/files",
+        data={"files": ""},
+    )
+    assert response.status_code == 200
+    assert response.json() == {"files_count": 1, "sizes": [0]}