From 845667f2d1eb7063c568764a01fc9ee633ec5817 Mon Sep 17 00:00:00 2001
From: Nick Pope <nick@nickpope.me.uk>
Date: Tue, 20 Jul 2021 16:28:25 +0100
Subject: [PATCH] Refs #32948 -- Simplified and optimized Q._combine() and
 __invert__().

- Removed use of Q.deconstruct() in Q._combine().
- Simplified and optimized Q.__invert__() by taking a shallow copy and
  swapping the negated attribute only.
- Simplified construction in Q._combine().
- Simplified conditions in Q._combine() as Q.conditional = True the
  first isinstance() check is unnecessary.
- Removed copy.copy() branch in Q._combine().

Co-authored-by: Keryn Knight <keryn@kerynknight.com>
---
 django/db/models/query_utils.py | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/django/db/models/query_utils.py b/django/db/models/query_utils.py
index 9b5824f89fe..d566cc18838 100644
--- a/django/db/models/query_utils.py
+++ b/django/db/models/query_utils.py
@@ -5,7 +5,6 @@ Factored out from django.db.models.query to avoid making the main module very
 large and/or so that they can be used by other modules without getting into
 circular import difficulties.
 """
-import copy
 import functools
 import inspect
 import logging
@@ -54,17 +53,14 @@ class Q(tree.Node):
         )
 
     def _combine(self, other, conn):
-        if not (isinstance(other, Q) or getattr(other, "conditional", False) is True):
+        if getattr(other, "conditional", False) is False:
             raise TypeError(other)
-
         if not self:
-            return other.copy() if hasattr(other, "copy") else copy.copy(other)
-        elif isinstance(other, Q) and not other:
-            _, args, kwargs = self.deconstruct()
-            return type(self)(*args, **kwargs)
+            return other.copy()
+        if not other and isinstance(other, Q):
+            return self.copy()
 
-        obj = type(self)()
-        obj.connector = conn
+        obj = self.create(connector=conn)
         obj.add(self, conn)
         obj.add(other, conn)
         return obj
@@ -79,8 +75,7 @@ class Q(tree.Node):
         return self._combine(other, self.XOR)
 
     def __invert__(self):
-        obj = type(self)()
-        obj.add(self, self.AND)
+        obj = self.copy()
         obj.negate()
         return obj