Add minimal GAP reproduction package

1 files changed, 13 insertions, 0 deletions

diff --git a/tests/test_store.py b/tests/test_store.py
new file mode 100644
index 0000000..f944130
--- /dev/null
+++ b/tests/test_store.py
@@ -0,0 +1,13 @@
+from __future__ import annotations
+
+import pytest
+
+from gap_pipeline.store import RunStore
+
+
+def test_store_refuses_conflicting_overwrite(tmp_path) -> None:
+    store = RunStore(tmp_path, "item")
+    store.write_json("artifact.json", {"value": 1})
+    store.write_json("artifact.json", {"value": 1})
+    with pytest.raises(FileExistsError, match="refusing to overwrite"):
+        store.write_json("artifact.json", {"value": 2})