Explicitly test for Connection in dialect.has_table()

The :meth:`_engine.Dialect.has_table` method now raises an informative
exception if a non-Connection is passed to it, as this incorrect behavior
seems to be common.  This method is not intended for external use outside
of a dialect.  Please use the :meth:`.Inspector.has_table` method
or for cross-compatibility with older SQLAlchemy versions, the
:meth:`_engine.Engine.has_table` method.

Fixes: #5780
Fixes: #6062
Fixes: #6260
Change-Id: I9b2439675167019b68d682edee3dcdcfce836987

1 files changed, 7 insertions, 0 deletions

diff --git a/test/engine/test_execute.py b/test/engine/test_execute.py
index 0de5ed124..0b65b3055 100644
--- a/test/engine/test_execute.py
+++ b/test/engine/test_execute.py
@@ -261,6 +261,13 @@ class ExecuteTest(fixtures.TablesTest):
             (4, "sally"),
         ]
 
+    def test_dialect_has_table_assertion(self):
+        with expect_raises_message(
+            tsa.exc.ArgumentError,
+            r"The argument passed to Dialect.has_table\(\) should be a",
+        ):
+            testing.db.dialect.has_table(testing.db, "some_table")
+
     def test_exception_wrapping_dbapi(self):
         with testing.db.connect() as conn:
             # engine does not have exec_driver_sql