diff --git a/tests/bugs/gh_8115_test.py b/tests/bugs/gh_8115_test.py
new file mode 100644
index 00000000..99b68e96
--- /dev/null
+++ b/tests/bugs/gh_8115_test.py
@@ -0,0 +1,99 @@
+#coding:utf-8
+
+"""
+ID:          issue-8115
+ISSUE:       https://github.com/FirebirdSQL/firebird/issues/8115
+TITLE:       Avoid reading/hashing the inner stream(s) if the leader stream is empty
+DESCRIPTION:
+    Original title: "FB 5.0.0.1306 - unexpected results using LEFT JOIN with When "
+NOTES:
+    [16.09.2024] pzotov
+    Confirmed bug in 5.0.1.1369-8c31082 (17.03.2024)
+    Bug was fixed in 5.0.1.1369-bbd35ab (20.03.2024)
+    Commit:
+        https://github.com/FirebirdSQL/firebird/commit/bbd35ab07c129e9735f081fcd29172a8187aa8ab
+        Avoid reading/hashing the inner stream(s) if the leader stream is empty
+
+    Checked on 6.0.0.457, 5.0.2.1499
+"""
+import zipfile
+from pathlib import Path
+import locale
+import re
+
+from firebird.driver import DatabaseError
+import pytest
+from firebird.qa import *
+
+db = db_factory()
+
+substitutions = [('INDEX_\\d+', 'INDEX_nn'),] 
+
+act = python_act('db', substitutions = substitutions)
+tmp_fbk = temp_file('gh_8115.tmp.fbk')
+
+#-----------------------------------------------------------
+
+def replace_leading(source, char="."):
+    stripped = source.lstrip()
+    return char * (len(source) - len(stripped)) + stripped
+
+#-----------------------------------------------------------
+
+@pytest.mark.version('>=5.0.1')
+def test_1(act: Action, tmp_fbk: Path, capsys):
+    zipped_fbk_file = zipfile.Path(act.files_dir / 'gh_8115.zip', at = 'gh_8115.fbk')
+    tmp_fbk.write_bytes(zipped_fbk_file.read_bytes())
+
+    act.gbak(switches = ['-rep', str(tmp_fbk), act.db.db_path], combine_output = True, io_enc = locale.getpreferredencoding())
+    print(act.stdout) # must be empty
+
+    test_sql = """
+        select aa.id, ab.CNP_USER, ab.ID_USER
+        from sal_inperioada2('7DC51501-0DF2-45BE-93E5-382A541505DE', '15.05.2024') aa
+        left join user_cnp(aa.cnp, '15.05.2024') ab on ab.CNP_USER = aa.cnp
+        where ab.ID_USER = '04B23787-2C7F-451A-A12C-309F79D6F13A'
+    """
+
+    with act.db.connect() as con:
+        cur = con.cursor()
+        ps = cur.prepare(test_sql)
+        print( '\n'.join([replace_leading(s) for s in ps.detailed_plan.split('\n')]) )
+
+        try:
+            cur.execute(ps)
+            for r in cur:
+                for p in r:
+                    print(p)
+        except DatabaseError as e:
+            print(e.__str__())
+            print(e.gds_codes)
+
+    expected_stdout_5x = """
+        Select Expression
+        ....-> Nested Loop Join (inner)
+        ........-> Procedure "SAL_INPERIOADA2" as "AA" Scan
+        ........-> Filter
+        ............-> Filter
+        ................-> Procedure "USER_CNP" as "AB" Scan
+
+        000DD4E1-B4D0-4D6E-9D9F-DE9A7D0D6492
+        E574F734-CECB-4A8F-B9BE-FAF51BC61FAD
+        04B23787-2C7F-451A-A12C-309F79D6F13A
+    """
+
+    expected_stdout_6x = """
+        Select Expression
+        ....-> Filter
+        ........-> Nested Loop Join (inner)
+        ............-> Procedure "SAL_INPERIOADA2" as "AA" Scan
+        ............-> Filter
+        ................-> Procedure "USER_CNP" as "AB" Scan
+        000DD4E1-B4D0-4D6E-9D9F-DE9A7D0D6492
+        E574F734-CECB-4A8F-B9BE-FAF51BC61FAD
+        04B23787-2C7F-451A-A12C-309F79D6F13A
+    """
+    
+    act.expected_stdout = expected_stdout_5x if act.is_version('<6') else expected_stdout_6x
+    act.stdout = capsys.readouterr().out
+    assert act.clean_stdout == act.clean_expected_stdout