Added/Updated tests\bugs\gh_7094_test.py: Checked on 5.0.0.1163, 4.0.4.2978. Test fails on 3.0.12 with 'invalid collation attribute', thus min_version was set to 4.0.2.

tests/bugs/gh_7094_test.py

@@ -0,0 +1,77 @@
+#coding:utf-8
+
+"""
+ID:          issue-7094
+ISSUE:       https://github.com/FirebirdSQL/firebird/issues/7094
+TITLE:       Incorrect indexed lookup of strings when the last keys characters are part of collated contractions and there is multi-segment insensitive descending index
+DESCRIPTION:
+NOTES:
+    [15.08.2023] pzotov
+    Confirmed problem on 5.0.0.425.
+    Checked on 5.0.0.1163, 4.0.4.2978.
+    Test fails on 3.0.12 with 'invalid collation attribute', thus min_version was set to 4.0.2.
+"""
+
+import pytest
+from firebird.qa import *
+
+db = db_factory()
+
+test_script = """
+    create collation unicode_ci_cz for utf8 from unicode case insensitive 'LOCALE=cs_CZ';
+
+    create table t1 (
+        c1 varchar(10) character set utf8 collate unicode_ci_cz,
+        c2 varchar(10) character set utf8 collate unicode_ci_cz
+    );
+
+    insert into t1 (c1) values ('a');
+    insert into t1 (c1) values ('b');
+    insert into t1 (c1) values ('c');
+    insert into t1 (c1) values ('ch');
+    insert into t1 (c1) values ('d');
+    insert into t1 (c1) values ('e');
+    insert into t1 (c1) values ('f');
+    update t1 set c2 = c1;
+    commit;
+
+    create desc index t1_c1_c2_desc on t1 (c1, c2);
+
+    set list on;
+    set plan on;
+
+    -- no data was displayed here before fix:
+    select t1.* from t1 where c1 > 'c' order by c1, c2;
+
+    select t1.* from t1 where c1 > 'c' plan (t1 natural) order by c1, c2;
+"""
+
+act = isql_act('db', test_script)
+
+expected_stdout = """
+    PLAN SORT (T1 INDEX (T1_C1_C2_DESC))
+    C1                              d
+    C2                              d
+    C1                              e
+    C2                              e
+    C1                              f
+    C2                              f
+    C1                              ch
+    C2                              ch
+
+    PLAN SORT (T1 NATURAL)
+    C1                              d
+    C2                              d
+    C1                              e
+    C2                              e
+    C1                              f
+    C2                              f
+    C1                              ch
+    C2                              ch
+"""
+
+@pytest.mark.version('>=4.0.2')
+def test_1(act: Action):
+    act.expected_stdout = expected_stdout
+    act.execute(combine_output = True)
+    assert act.clean_stdout == act.clean_expected_stdout