Added/Updated tests\bugs\gh_8589_test.py: Checked on 6.0.0.797-bc305e6; 5.0.3.1369-fe53465; 4.0.6.3206-9580691

Author: pavel-zotov

tests/bugs/gh_8589_test.py

@@ -0,0 +1,83 @@
+#coding:utf-8
+
+"""
+ID:          issue-8589
+ISSUE:       https://github.com/FirebirdSQL/firebird/issues/8589
+TITLE:       PERCENT_RANK may return NaN instead of 0
+DESCRIPTION:
+NOTES:
+    [07.06.2025] pzotov
+    Confirmed bug on 6.0.0.797-0-303e8d4
+    Checked on 6.0.0.797-bc305e6; 5.0.3.1369-fe53465; 4.0.6.3206-9580691
+"""
+
+import pytest
+from firebird.qa import *
+
+db = db_factory()
+
+test_script = """
+
+    set list on;
+    recreate table test(
+        id integer not null,
+        the_int integer,
+        primary key (id)
+    );
+
+    insert into test(the_int, id) values (5, 1);
+    insert into test(the_int, id) values (6, 2);
+    insert into test(the_int, id) values (7, 3);
+    insert into test(the_int, id) values (13, 4);
+    insert into test(the_int, id) values (5, 5);
+
+    select
+        id,
+        the_int,
+        row_number() over(partition by t.the_int order by t.id),
+        percent_rank() over(partition by t.the_int order by t.id),
+        cume_dist() over(partition by t.the_int order by t.id) 
+    from test t 
+    order by 1;
+"""
+
+act = isql_act('db', test_script, substitutions = [('[\t ]+', ' ')])
+
+expected_stdout = """
+    ID 1
+    THE_INT 5
+    ROW_NUMBER 1
+    PERCENT_RANK 0.000000000000000
+    CUME_DIST 0.5000000000000000
+
+    ID 2
+    THE_INT 6
+    ROW_NUMBER 1
+    PERCENT_RANK 0.000000000000000
+    CUME_DIST 1.000000000000000
+
+    ID 3
+    THE_INT 7
+    ROW_NUMBER 1
+    PERCENT_RANK 0.000000000000000
+    CUME_DIST 1.000000000000000
+
+    ID 4
+    THE_INT 13
+    ROW_NUMBER 1
+    PERCENT_RANK 0.000000000000000
+    CUME_DIST 1.000000000000000
+
+    ID 5
+    THE_INT 5
+    ROW_NUMBER 2
+    PERCENT_RANK 1.000000000000000
+    CUME_DIST 1.000000000000000
+"""
+
+@pytest.mark.version('>=4.0.6')
+def test_1(act: Action):
+    act.expected_stdout = expected_stdout
+    act.execute(combine_output = True)
+    assert act.clean_stdout == act.clean_expected_stdout
+