Fix(clickhouse): traverse_scope with FINAL modifier (#4263)

Fixes #4262

sqlglot/optimizer/scope.py

@@ -679,6 +679,8 @@ def _traverse_tables(scope):
     expressions.extend(scope.expression.args.get("laterals") or [])
 
     for expression in expressions:
+        if isinstance(expression, exp.Final):
+            expression = expression.this
         if isinstance(expression, exp.Table):
             table_name = expression.name
             source_name = expression.alias_or_name

tests/dialects/test_clickhouse.py

@@ -2,6 +2,7 @@
 from sqlglot import exp, parse_one
 from sqlglot.dialects import ClickHouse
 from sqlglot.expressions import convert
+from sqlglot.optimizer import traverse_scope
 from tests.dialects.test_dialect import Validator
 from sqlglot.errors import ErrorLevel
 
@@ -1123,3 +1124,9 @@ def test_array_join(self):
         self.validate_identity(
             "SELECT * FROM arrays_test ARRAY JOIN [1, 2, 3] AS arr_external1, ['a', 'b', 'c'] AS arr_external2, splitByString(',', 'asd,qwerty,zxc') AS arr_external3"
         )
+
+    def test_traverse_scope(self):
+        sql = "SELECT * FROM t FINAL"
+        scopes = traverse_scope(parse_one(sql, dialect=self.dialect))
+        self.assertEqual(len(scopes), 1)
+        self.assertEqual(set(scopes[0].sources), {"t"})