Allow Grouping to pass along proxy_set of element

Repaired an issue where the "ORDER BY" clause rendering a label name rather
than a complete expression, which is particularly important for SQL Server,
would fail to occur if the expression were enclosed in a parenthesized
grouping in some cases.   This case has been added to test support.

Fixes: #5470
Change-Id: Ie0e27c39e5d53be78b32f7810f93d2d0536375e7

1 files changed, 20 insertions, 0 deletions

diff --git a/test/sql/test_text.py b/test/sql/test_text.py
index 58de41709..1a7ee6f34 100644
--- a/test/sql/test_text.py
+++ b/test/sql/test_text.py
@@ -15,6 +15,7 @@ from sqlalchemy import MetaData
 from sqlalchemy import select
 from sqlalchemy import String
 from sqlalchemy import Table
+from sqlalchemy import testing
 from sqlalchemy import text
 from sqlalchemy import union
 from sqlalchemy import util
@@ -710,6 +711,25 @@ class OrderByLabelResolutionTest(fixtures.TestBase, AssertsCompiledSQL):
             "FROM mytable AS mytable_1 ORDER BY mytable_1.name",
         )
 
+    @testing.combinations(
+        ((column("q") + 5).label("a"), "a", ()),
+        (column("q").op("+")(5).label("a"), "a", ()),
+        ((column("q") + 5).label("a"), "a DESC", (desc,)),
+        (column("q").op("+")(5).label("a"), "a DESC", (desc,)),
+    )
+    def test_order_by_expr(self, case, expected, modifiers):
+
+        order_by = case
+        for mod in modifiers:
+            order_by = mod(order_by)
+
+        stmt = select([case]).order_by(order_by)
+
+        col_expr = str(case)
+        self.assert_compile(
+            stmt, "SELECT %s AS a ORDER BY %s" % (col_expr, expected)
+        )
+
     def test_order_by_named_label_from_anon_label(self):
         s1 = select([table1.c.myid.label(None).label("foo"), table1.c.name])
         stmt = s1.order_by("foo")