Added/Updated tests\bugs\gh_8112_test.py: Checked on 6.0.0.351, 5.0.1.1399.

tests/bugs/gh_8112_test.py

@@ -0,0 +1,45 @@
+#coding:utf-8
+
+"""
+ID:          issue-8112
+ISSUE:       https://github.com/FirebirdSQL/firebird/issues/8112
+TITLE:       Error isc_read_only_trans (335544361) should report SQLSTATE 25006.
+DESCRIPTION:
+NOTES:
+    Confirmed problem on 6.0.0.345,  5.0.1.1395.
+    Checked on 6.0.0.351, 5.0.1.1399.
+"""
+import pytest
+from firebird.qa import *
+from firebird.driver import tpb, Isolation, TraLockResolution, TraAccessMode, DatabaseError
+
+init_sql = """
+    recreate table test(id int default current_transaction);
+"""
+db = db_factory(init = init_sql)
+act = python_act('db', substitutions = [('[ \t]+', ' ')])
+
+@pytest.mark.version('>=5.0.1')
+def test_1(act: Action, capsys):
+
+    try:
+        custom_tpb = tpb(isolation = Isolation.SERIALIZABLE, access_mode = TraAccessMode.READ)
+        with act.db.connect() as con:
+            tx = con.transaction_manager(custom_tpb)
+            cur = tx.cursor()
+            cur.execute('insert into test default values')
+            con.commit()
+            
+    except DatabaseError as e:
+        print(e.sqlstate) # must be '25006' after fix.
+        print(e.__str__())
+        for g in e.gds_codes:
+            print(g)
+
+    act.expected_stdout = f"""
+        25006
+        attempted update during read-only transaction
+        335544361
+    """
+    act.stdout = capsys.readouterr().out
+    assert act.clean_stdout == act.clean_expected_stdout