Improved Model.__init__() properties loop.

This improves readability, accumulates unrecognized arguments raise an
exception with all of them, and avoids refetching the values.

django/db/models/base.py

@@ -513,18 +513,27 @@ class Model(metaclass=ModelBase):
 
         if kwargs:
             property_names = opts._property_names
-            for prop in tuple(kwargs):
-                try:
-                    # Any remaining kwargs must correspond to properties or
-                    # virtual fields.
-                    if prop in property_names or opts.get_field(prop):
-                        if kwargs[prop] is not _DEFERRED:
-                            _setattr(self, prop, kwargs[prop])
-                        del kwargs[prop]
-                except (AttributeError, FieldDoesNotExist):
-                    pass
-            for kwarg in kwargs:
-                raise TypeError("%s() got an unexpected keyword argument '%s'" % (cls.__name__, kwarg))
+            unexpected = ()
+            for prop, value in kwargs.items():
+                # Any remaining kwargs must correspond to properties or virtual
+                # fields.
+                if prop in property_names:
+                    if value is not _DEFERRED:
+                        _setattr(self, prop, value)
+                else:
+                    try:
+                        opts.get_field(prop)
+                    except FieldDoesNotExist:
+                        unexpected += (prop,)
+                    else:
+                        if value is not _DEFERRED:
+                            _setattr(self, prop, value)
+            if unexpected:
+                unexpected_names = ', '.join(repr(n) for n in unexpected)
+                raise TypeError(
+                    f'{cls.__name__}() got unexpected keyword arguments: '
+                    f'{unexpected_names}'
+                )
         super().__init__()
         post_init.send(sender=cls, instance=self)
 

tests/basic/tests.py

@@ -78,13 +78,23 @@ class ModelInstanceCreationTests(TestCase):
             Article(None, 'Seventh article', datetime(2021, 3, 1), pub_date=None)
 
     def test_cannot_create_instance_with_invalid_kwargs(self):
-        with self.assertRaisesMessage(TypeError, "Article() got an unexpected keyword argument 'foo'"):
+        msg = "Article() got unexpected keyword arguments: 'foo'"
+        with self.assertRaisesMessage(TypeError, msg):
             Article(
                 id=None,
                 headline='Some headline',
                 pub_date=datetime(2005, 7, 31),
                 foo='bar',
             )
+        msg = "Article() got unexpected keyword arguments: 'foo', 'bar'"
+        with self.assertRaisesMessage(TypeError, msg):
+            Article(
+                id=None,
+                headline='Some headline',
+                pub_date=datetime(2005, 7, 31),
+                foo='bar',
+                bar='baz',
+            )
 
     def test_can_leave_off_value_for_autofield_and_it_gets_value_on_save(self):
         """

tests/properties/tests.py

@@ -18,7 +18,7 @@ class PropertyTests(TestCase):
             setattr(self.a, 'full_name', 'Paul McCartney')
 
         # And cannot be used to initialize the class.
-        with self.assertRaisesMessage(TypeError, "Person() got an unexpected keyword argument 'full_name'"):
+        with self.assertRaises(AttributeError):
             Person(full_name='Paul McCartney')
 
         # But "full_name_2" has, and it can be used to initialize the class.