Added/Updated tests\bugs\gh_7879_test.py: Checked 6.0.0.154, 5.0.0.1280

tests/bugs/gh_7879_test.py

@@ -0,0 +1,43 @@
+#coding:utf-8
+
+"""
+ID:          issue-7879
+ISSUE:       7879
+TITLE:       Unexpected Results when Using Natural Right Join
+DESCRIPTION:
+NOTES:
+    [27.11.2023] pzotov
+    Checked 6.0.0.154, 5.0.0.1280
+"""
+
+import pytest
+from firebird.qa import *
+
+db = db_factory()
+
+test_script = """
+    recreate table t0(c0 int, c1 int);
+    recreate table t1(c0 int);
+
+    insert into t0(c0, c1) values (1, 2);
+    insert into t1( c0) values (3);
+
+    set list on;
+    set count on;
+
+    select * from t0 natural right join t1 where ((c0 in (c0, c1))); 
+"""
+
+act = isql_act('db', test_script)
+
+expected_stdout = """
+    C0                              3
+    C1                              <null>
+    Records affected: 1
+"""
+
+@pytest.mark.version('>=5.0')
+def test_1(act: Action):
+    act.expected_stdout = expected_stdout
+    act.execute(combine_output = True)
+    assert act.clean_stdout == act.clean_expected_stdout