Added/Updated tests\bugs\gh_7237_test.py: Cheched on 5.0.0.958; 4.0.3.2903; 3.0.11.33664 - all fine.

tests/bugs/gh_7237_test.py

@@ -0,0 +1,52 @@
+#coding:utf-8
+
+"""
+ID:          issue-7237
+ISSUE:       7237
+TITLE:       Starting operator become unstable on indexed varchar fields
+NOTES:
+    [22.02.2023] pzotov
+	Confirmed bug on 3.0.10.33601
+    Cheched on 5.0.0.958; 4.0.3.2903; 3.0.11.33664 - all fine.
+"""
+
+import pytest
+from firebird.qa import *
+
+db = db_factory(charset = 'utf8')
+
+test_script = """
+    set list on;
+    create table test(id int, str_field varchar(10) character set utf8 collate unicode_ci);
+    create index test_idx1 on test (str_field);
+    insert into test(id, str_field) values(1, 'ПАПА');
+
+    -- Tests
+    set count on;
+    select id from test where str_field starting 'П';    -- Found
+    select id from test where str_field starting 'ПА';   -- Not found
+    select id from test where str_field starting 'ПАП';  -- Found
+    select id from test where str_field starting 'ПАПА'; -- Not found
+"""
+
+expected_stdout = """
+    ID                              1
+    Records affected: 1
+
+    ID                              1
+    Records affected: 1
+
+    ID                              1
+    Records affected: 1
+
+    ID                              1
+    Records affected: 1
+"""
+
+act = isql_act('db', test_script)
+
+@pytest.mark.version('>=3.0.10')
+def test_1(act: Action):
+    act.expected_stdout = expected_stdout
+    act.execute(combine_output = True, charset = 'utf8')
+    assert act.clean_stdout == act.clean_expected_stdout