id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
32455	Q(...) & Exists(...) raises a TypeError	john-parton	Hasan Ramezani	"Exists(...) & Q(...) works, but Q(...) & Exists(...) raise a TypeError

Here's a minimal example:


{{{
In [3]: Exists(Product.objects.all()) & Q()
Out[3]: <Q: (AND: <django.db.models.expressions.Exists object at 0x7fc18dd0ed90>, (AND: ))>

In [4]: Q() & Exists(Product.objects.all())
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-4-21d3dea0fcb9> in <module>
----> 1 Q() & Exists(Product.objects.all())

~/Code/venv/ecom/lib/python3.8/site-packages/django/db/models/query_utils.py in __and__(self, other)
     90 
     91     def __and__(self, other):
---> 92         return self._combine(other, self.AND)
     93 
     94     def __invert__(self):

~/Code/venv/ecom/lib/python3.8/site-packages/django/db/models/query_utils.py in _combine(self, other, conn)
     71     def _combine(self, other, conn):
     72         if not isinstance(other, Q):
---> 73             raise TypeError(other)
     74 
     75         # If the other Q() is empty, ignore it and just use `self`.

TypeError: <django.db.models.expressions.Exists object at 0x7fc18dd21400>
}}}



The & (and |) operators should be commutative on Q-Exists pairs, but it's not

I think there's a missing definition of `__rand__` somewhere."	Bug	closed	Database layer (models, ORM)	3.1	Normal	fixed		Matthew Schinckel	Ready for checkin	1	0	0	0	0	0