Added utils module, ref #14

git_history/utils.py

@@ -0,0 +1,19 @@
+import re
+
+RESERVED = ("_id", "_item", "_version", "_commit", "rowid")
+reserved_with_suffix_re = re.compile("^({})_*$".format("|".join(RESERVED)))
+
+
+def fix_reserved_columns(item):
+    if not any(reserved_with_suffix_re.match(key) for key in item):
+        return item
+
+    return {_fix_key(key): item[key] for key in item}
+
+
+def _fix_key(key):
+    # Add a trailing _ if it's reserved or reserved with _ suffix
+    if reserved_with_suffix_re.match(key):
+        return key + "_"
+    else:
+        return key

tests/test_utils.py

@@ -0,0 +1,27 @@
+from git_history.utils import fix_reserved_columns
+import pytest
+
+
+@pytest.mark.parametrize(
+    "column,expected",
+    (
+        ("_id", "_id_"),
+        ("_item", "_item_"),
+        ("_version", "_version_"),
+        ("_commit", "_commit_"),
+        ("rowid", "rowid_"),
+        ("rowid_", "rowid__"),
+        ("_id__", "_id___"),
+    ),
+)
+def test_fix_reserved_columns(column, expected):
+    item = {column: 1}
+    fixed = fix_reserved_columns(item)
+    assert fixed == {expected: 1}
+    assert item is not fixed
+
+
+def test_fix_reserved_columns_unchanged_if_no_reserved():
+    item = {"id": 1, "version": "v2"}
+    fixed = fix_reserved_columns(item)
+    assert item is fixed