Issue #18219: Optimize csv.DictWriter for large number of columns.
Patch by Mariatta Wijaya.
diff --git a/Lib/test/test_csv.py b/Lib/test/test_csv.py
index 7dcea9c..03ab184 100644
--- a/Lib/test/test_csv.py
+++ b/Lib/test/test_csv.py
@@ -626,6 +626,24 @@
self.assertNotIn("'f2'", exception)
self.assertIn("1", exception)
+ def test_typo_in_extrasaction_raises_error(self):
+ fileobj = StringIO()
+ self.assertRaises(ValueError, csv.DictWriter, fileobj, ['f1', 'f2'],
+ extrasaction="raised")
+
+ def test_write_field_not_in_field_names_raise(self):
+ fileobj = StringIO()
+ writer = csv.DictWriter(fileobj, ['f1', 'f2'], extrasaction="raise")
+ dictrow = {'f0': 0, 'f1': 1, 'f2': 2, 'f3': 3}
+ self.assertRaises(ValueError, csv.DictWriter.writerow, writer, dictrow)
+
+ def test_write_field_not_in_field_names_ignore(self):
+ fileobj = StringIO()
+ writer = csv.DictWriter(fileobj, ['f1', 'f2'], extrasaction="ignore")
+ dictrow = {'f0': 0, 'f1': 1, 'f2': 2, 'f3': 3}
+ csv.DictWriter.writerow(writer, dictrow)
+ self.assertEqual(fileobj.getvalue(), "1,2\r\n")
+
def test_read_dict_fields(self):
with TemporaryFile("w+") as fileobj:
fileobj.write("1,2,abc\r\n")