should be it

external/duckdb/test/sql/copy/csv/test_12596.test

@@ -0,0 +1,24 @@
+# name: test/sql/copy/csv/test_12596.test
+# description: CSV reader: combination of null_padding = true and parallel = false introduces extra row #12596
+# group: [csv]
+
+statement ok
+PRAGMA enable_verification
+
+query III
+from read_csv('data/csv/bug_12596.csv', skip=1, delim=',', header=false, columns={'c1': 'INTEGER', 'c2': 'INTEGER', 'column2': 'VARCHAR'}, null_padding = true);
+----
+1	2	NULL
+3	4	NULL
+
+query III
+from read_csv('data/csv/bug_12596.csv', skip=1, delim=',', header=false, columns={'c1': 'INTEGER', 'c2': 'INTEGER', 'column2': 'VARCHAR'}, null_padding = true, parallel = false, auto_detect = false);
+----
+1	2	NULL
+3	4	NULL
+
+query III
+from read_csv('data/csv/bug_12596.csv', skip=1, delim=',', header=false, columns={'c1': 'INTEGER', 'c2': 'INTEGER', 'column2': 'VARCHAR'}, null_padding = true, parallel = false);
+----
+1	2	NULL
+3	4	NULL