Report the type of unexpected expression objects

diff --git a/lib/sqlalchemy/sql/elements.py b/lib/sqlalchemy/sql/elements.py
index 734f78632b69ef036bda447ae7ff168a6f04020a..4c66061c83376a5b86e3d83fe36ce75ea12d5338 100644 (file)
--- a/lib/sqlalchemy/sql/elements.py
+++ b/lib/sqlalchemy/sql/elements.py
@@ -3732,7 +3732,8 @@ def _literal_as_text(element, warn=False):
         return _const_expr(element)
     else:
         raise exc.ArgumentError(
-            "SQL expression object or string expected."
+            "SQL expression object or string expected, got object of type %r "
+            "instead" % type(element)
         )
 
 

diff --git a/test/sql/test_defaults.py b/test/sql/test_defaults.py
index 10e557b76cf6f185b740be9118d4d673ce8df622..21d04ea38511649a6ad2554b918792eff98c74d5 100644 (file)
--- a/test/sql/test_defaults.py
+++ b/test/sql/test_defaults.py
@@ -368,7 +368,8 @@ class DefaultTest(fixtures.TestBase):
         ):
             assert_raises_message(
                 sa.exc.ArgumentError,
-                "SQL expression object or string expected.",
+                "SQL expression object or string expected, got object of type "
+                "<type 'list'> instead",
                 t.select, [const]
             )
             assert_raises_message(