From ac20c3d34bf0127972acae8c712b98b1187b98f9 Mon Sep 17 00:00:00 2001
From: MajorDallas <79329882+MajorDallas@users.noreply.github.com>
Date: Tue, 22 Jun 2021 15:34:09 -0400
Subject: [PATCH] Add impl property to PostgreSQL / Oracle INTERVAL class

Fixed issue where the ``INTERVAL`` datatype on PostgreSQL and Oracle would
produce an ``AttributeError`` when used in the context of a comparison
operation against a ``timedelta()`` object. Pull request courtesy
MajorDallas.

Fixes: #6649
Closes: #6650
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/6650
Pull-request-sha: dd217a975e5f0d3157e81c731791225b6a32889f

Change-Id: I773caf2673294fdb3c92b42895ad714e944d1bf8
---
 doc/build/changelog/unreleased_14/6649.rst | 8 ++++++++
 lib/sqlalchemy/dialects/oracle/base.py     | 3 +++
 lib/sqlalchemy/dialects/postgresql/base.py | 3 +++
 test/dialect/oracle/test_types.py          | 4 ++++
 test/dialect/postgresql/test_types.py      | 4 ++++
 5 files changed, 22 insertions(+)
 create mode 100644 doc/build/changelog/unreleased_14/6649.rst

diff --git a/doc/build/changelog/unreleased_14/6649.rst b/doc/build/changelog/unreleased_14/6649.rst
new file mode 100644
index 0000000000..70ec64216d
--- /dev/null
+++ b/doc/build/changelog/unreleased_14/6649.rst
@@ -0,0 +1,8 @@
+.. change::
+    :tags: bug, postgresql, oracle
+    :tickets: 6649
+
+    Fixed issue where the ``INTERVAL`` datatype on PostgreSQL and Oracle would
+    produce an ``AttributeError`` when used in the context of a comparison
+    operation against a ``timedelta()`` object. Pull request courtesy
+    MajorDallas.
diff --git a/lib/sqlalchemy/dialects/oracle/base.py b/lib/sqlalchemy/dialects/oracle/base.py
index 57f55c1824..a72088a461 100644
--- a/lib/sqlalchemy/dialects/oracle/base.py
+++ b/lib/sqlalchemy/dialects/oracle/base.py
@@ -702,6 +702,9 @@ class INTERVAL(sqltypes.NativeForEmulated, sqltypes._AbstractInterval):
             day_precision=self.day_precision,
         )
 
+    def coerce_compared_value(self, op, value):
+        return self
+
 
 class ROWID(sqltypes.TypeEngine):
     """Oracle ROWID type.
diff --git a/lib/sqlalchemy/dialects/postgresql/base.py b/lib/sqlalchemy/dialects/postgresql/base.py
index deb6243296..4c78981329 100644
--- a/lib/sqlalchemy/dialects/postgresql/base.py
+++ b/lib/sqlalchemy/dialects/postgresql/base.py
@@ -1655,6 +1655,9 @@ class INTERVAL(sqltypes.NativeForEmulated, sqltypes._AbstractInterval):
     def python_type(self):
         return dt.timedelta
 
+    def coerce_compared_value(self, op, value):
+        return self
+
 
 PGInterval = INTERVAL
 
diff --git a/test/dialect/oracle/test_types.py b/test/dialect/oracle/test_types.py
index 4b11960257..70b00c06f2 100644
--- a/test/dialect/oracle/test_types.py
+++ b/test/dialect/oracle/test_types.py
@@ -183,6 +183,10 @@ class DialectTypesTest(fixtures.TestBase, AssertsCompiledSQL):
     def test_interval(self, type_, expected):
         self.assert_compile(type_, expected)
 
+    def test_interval_coercion_literal(self):
+        expr = column("bar", oracle.INTERVAL) == datetime.timedelta(days=1)
+        eq_(expr.right.type._type_affinity, sqltypes.Interval)
+
 
 class TypesTest(fixtures.TestBase):
     __only_on__ = "oracle"
diff --git a/test/dialect/postgresql/test_types.py b/test/dialect/postgresql/test_types.py
index c83fe0f8a1..3fdb31b7cb 100644
--- a/test/dialect/postgresql/test_types.py
+++ b/test/dialect/postgresql/test_types.py
@@ -2427,6 +2427,10 @@ class TimestampTest(fixtures.TestBase, AssertsExecutionResults):
         eq_(expr.type._type_affinity, types.Interval)
         assert isinstance(expr.type, postgresql.INTERVAL)
 
+    def test_interval_coercion_literal(self):
+        expr = column("bar", postgresql.INTERVAL) == datetime.timedelta(days=1)
+        eq_(expr.right.type._type_affinity, types.Interval)
+
 
 class SpecialTypesCompileTest(fixtures.TestBase, AssertsCompiledSQL):
     __dialect__ = "postgresql"
-- 
2.47.2