Allow NUMERIC()/DECIMAL() IDENTITY columns

Fixed issue where :class:`.Table` objects that made use of IDENTITY columns
with a :class:`.Numeric` datatype would produce errors when attempting to
reconcile the "autoincrement" column, preventing construction of the
:class:`.Column` from using the :paramref:`.Column.autoincrement` parameter
as well as emitting errors when attempting to invoke an :class:`.Insert`
construct.

Fixes: #8111
Change-Id: Iaacc4eebfbafb42fa18f9a1a4f43cb2b6b91d28a

1 files changed, 17 insertions, 0 deletions

diff --git a/test/dialect/mssql/test_query.py b/test/dialect/mssql/test_query.py
index 3576a9fc2..29bf4c812 100644
--- a/test/dialect/mssql/test_query.py
+++ b/test/dialect/mssql/test_query.py
@@ -1,4 +1,6 @@
 # -*- encoding: utf-8
+import decimal
+
 from sqlalchemy import and_
 from sqlalchemy import Column
 from sqlalchemy import DDL
@@ -9,6 +11,7 @@ from sqlalchemy import func
 from sqlalchemy import Identity
 from sqlalchemy import Integer
 from sqlalchemy import literal
+from sqlalchemy import Numeric
 from sqlalchemy import or_
 from sqlalchemy import PrimaryKeyConstraint
 from sqlalchemy import select
@@ -39,6 +42,13 @@ class IdentityInsertTest(fixtures.TablesTest, AssertsCompiledSQL):
             Column("description", String(50)),
             PrimaryKeyConstraint("id", name="PK_cattable"),
         )
+        Table(
+            "numeric_identity",
+            metadata,
+            Column("id", Numeric(18, 0), autoincrement=True),
+            Column("description", String(50)),
+            PrimaryKeyConstraint("id", name="PK_numeric_identity"),
+        )
 
     def test_compiled(self):
         cattable = self.tables.cattable
@@ -61,6 +71,13 @@ class IdentityInsertTest(fixtures.TablesTest, AssertsCompiledSQL):
         lastcat = conn.execute(cattable.select().order_by(desc(cattable.c.id)))
         eq_((10, "PHP"), lastcat.first())
 
+        numeric_identity = self.tables.numeric_identity
+        # for some reason, T-SQL does not like .values(), but this works
+        result = conn.execute(
+            numeric_identity.insert(), dict(description="T-SQL")
+        )
+        eq_(result.inserted_primary_key, (decimal.Decimal("1"),))
+
     def test_executemany(self, connection):
         conn = connection
         cattable = self.tables.cattable