establish consistency for RETURNING column labels

The RETURNING clause now renders columns using the routine as that of the
:class:`.Select` to generate labels, which will include disambiguating
labels, as well as that a SQL function surrounding a named column will be
labeled using the column name itself. This is a more comprehensive change
than a similar one made for the 1.4 series that adjusted the function label
issue only.

includes 1.4's changelog for the backported version which also
fixes an Oracle issue independently of the 2.0 series.

Fixes: #8770
Change-Id: I2ab078a214a778ffe1720dbd864ae4c105a0691d

1 files changed, 29 insertions, 0 deletions

diff --git a/test/dialect/mssql/test_compiler.py b/test/dialect/mssql/test_compiler.py
index 8605ea9c0..b575595ac 100644
--- a/test/dialect/mssql/test_compiler.py
+++ b/test/dialect/mssql/test_compiler.py
@@ -36,6 +36,7 @@ from sqlalchemy.testing import eq_
 from sqlalchemy.testing import fixtures
 from sqlalchemy.testing import is_
 from sqlalchemy.testing.assertions import eq_ignore_whitespace
+from sqlalchemy.types import TypeEngine
 
 tbl = table("t", column("a"))
 
@@ -119,6 +120,34 @@ class CompileTest(fixtures.TestBase, AssertsCompiledSQL):
             "Latin1_General_CS_AS_KS_WS_CI ASC",
         )
 
+    @testing.fixture
+    def column_expression_fixture(self):
+        class MyString(TypeEngine):
+            def column_expression(self, column):
+                return func.lower(column)
+
+        return table(
+            "some_table", column("name", String), column("value", MyString)
+        )
+
+    @testing.combinations("columns", "table", argnames="use_columns")
+    def test_plain_returning_column_expression(
+        self, column_expression_fixture, use_columns
+    ):
+        """test #8770"""
+        table1 = column_expression_fixture
+
+        if use_columns == "columns":
+            stmt = insert(table1).returning(table1)
+        else:
+            stmt = insert(table1).returning(table1.c.name, table1.c.value)
+
+        self.assert_compile(
+            stmt,
+            "INSERT INTO some_table (name, value) OUTPUT inserted.name, "
+            "lower(inserted.value) AS value VALUES (:name, :value)",
+        )
+
     def test_join_with_hint(self):
         t1 = table(
             "t1",