Tests for rows_from_file, refs #440

tests/test_rows_from_file.py

@@ -0,0 +1,46 @@
+from sqlite_utils.utils import rows_from_file, Format, RowError
+from io import BytesIO
+import pytest
+
+
+@pytest.mark.parametrize(
+    "input,expected_format",
+    (
+        (b"id,name\n1,Cleo", Format.CSV),
+        (b"id\tname\n1\tCleo", Format.TSV),
+        (b'[{"id": "1", "name": "Cleo"}]', Format.JSON),
+    ),
+)
+def test_rows_from_file_detect_format(input, expected_format):
+    rows, format = rows_from_file(BytesIO(input))
+    assert format == expected_format
+    rows_list = list(rows)
+    assert rows_list == [{"id": "1", "name": "Cleo"}]
+
+
+@pytest.mark.parametrize(
+    "ignore_extras,restkey,expected",
+    (
+        (True, None, [{"id": "1", "name": "Cleo"}]),
+        (False, "_rest", [{"id": "1", "name": "Cleo", "_rest": ["oops"]}]),
+        # expected of None means expect an error:
+        (False, False, None),
+    ),
+)
+def test_rows_from_file_extra_fields_strategies(ignore_extras, restkey, expected):
+    try:
+        rows, format = rows_from_file(
+            BytesIO(b"id,name\r\n1,Cleo,oops"),
+            format=Format.CSV,
+            ignore_extras=ignore_extras,
+            restkey=restkey,
+        )
+        list_rows = list(rows)
+    except RowError:
+        if expected is None:
+            # This is fine,
+            return
+        else:
+            # We did not expect an error
+            raise
+    assert list_rows == expected