Handle Coalesce in updates

Modeled on #534, which
I see came out of a similar issue as I've been seeing now:
"AttributeError: 'Coalesce' object has no attribute 'rhs'

djmoney/models/managers.py

@@ -4,7 +4,7 @@
 from django.db.models import NOT_PROVIDED, Case, F, Q
 from django.db.models.constants import LOOKUP_SEP
 from django.db.models.expressions import BaseExpression
-from django.db.models.functions import Cast
+from django.db.models.functions import Cast, Coalesce
 from django.utils.encoding import smart_str
 
 from ..utils import MONEY_CLASSES, get_currency_field_name, prepare_expression
@@ -142,7 +142,7 @@ def _expand_money_kwargs(model, args=(), kwargs=None, exclusions=()):
             kwargs[currency_field_name] = smart_str(value.currency)
         else:
             if isinstance(field, MoneyField):
-                if isinstance(value, (BaseExpression, F)) and not isinstance(value, (Case, Cast)):
+                if isinstance(value, (BaseExpression, F)) and not isinstance(value, (Case, Cast, Coalesce)):
                     clean_name = _get_clean_name(model, name)
                     if not isinstance(value, F):
                         value = prepare_expression(value)

docs/changes.rst

@@ -1,6 +1,13 @@
 Changelog
 =========
 
+`Unreleased`_ - TBA
+-------------------
+
+**Fixed**
+
+- Support for ``Money`` type with ``Coalesce`` in ``QuerySet.update()`` `#678`_ (`stianjensen`_)
+
 
 `3.0`_ - 2022-06-20
 --------------------
@@ -737,6 +744,7 @@ wrapping with ``money_manager``.
 
 - Initial public release
 
+.. _Unreleased: https:///github.com/django-money/django-money/compare/3.0...HEAD
 .. _3.0: https:///github.com/django-money/django-money/compare/2.1.1...3.0
 .. _2.1.1: https:///github.com/django-money/django-money/compare/2.1...2.1.1
 .. _2.1: https:///github.com/django-money/django-money/compare/2.0.3...2.1
@@ -915,6 +923,7 @@ wrapping with ``money_manager``.
 .. _#519: https://github.com/django-money/django-money/issues/519
 .. _#521: https://github.com/django-money/django-money/issues/521
 .. _#522: https://github.com/django-money/django-money/issues/522
+.. _#678: https://github.com/django-money/django-money/pull/678
 
 
 .. _77cc33: https://github.com/77cc33
@@ -983,6 +992,7 @@ wrapping with ``money_manager``.
 .. _sjdines: https://github.com/sjdines
 .. _snbuchholz: https://github.com/snbuchholz
 .. _spookylukey: https://github.com/spookylukey
+.. _stianjensen: https://github.com/stianjensen
 .. _stinovlas: https://github.com/stinovlas
 .. _synotna: https://github.com/synotna
 .. _tned73: https://github.com/tned73

tests/test_models.py

@@ -12,6 +12,7 @@
 from django.db import IntegrityError, models
 from django.db.migrations.writer import MigrationWriter
 from django.db.models import Case, F, Func, Q, Value, When
+from django.db.models.functions import Coalesce
 from django.utils.translation import override
 
 import pytest
@@ -624,6 +625,14 @@ def test_conditional_update(self):
         assert ModelWithVanillaMoneyField.objects.get(integer=0).money == Money(10, "USD")
         assert ModelWithVanillaMoneyField.objects.get(integer=1).money == Money(0, "USD")
 
+    def test_update_with_coalesce(self):
+        ModelWithVanillaMoneyField.objects.create(money=Money(1, "USD"), second_money=Money(2, "USD"), integer=0)
+        ModelWithVanillaMoneyField.objects.update(
+            money=Coalesce(F("second_money"), 0, output_field=models.DecimalField())
+        )
+        instance = ModelWithVanillaMoneyField.objects.get()
+        assert instance.money == Money("2", "USD")
+
     def test_create_func(self):
         instance = ModelWithVanillaMoneyField.objects.create(
             money=Func(Value(-10), function="ABS"), money_currency="USD"