Respect limit_choices_to for ForeignKey relations (fixes iommirocks#441)

Author: boxed

iommi/_db_compat.py

@@ -176,6 +176,16 @@ def setup_db_compat_iommi():
     register_edit_column_factory(SortOrderField, shortcut_name='reorder_handle')
 
 
+def choices_from_model_field(model, model_field):
+    queryset = model.objects.all()
+    limit_choices_to = model_field.remote_field.limit_choices_to
+    if limit_choices_to:
+        if callable(limit_choices_to):
+            limit_choices_to = limit_choices_to()
+        queryset = queryset.complex_filter(limit_choices_to)
+    return queryset
+
+
 def base_defaults_factory(model_field):
     from iommi.base import capitalize
 

iommi/form.py

@@ -46,7 +46,10 @@
 from django.utils.translation import gettext_lazy
 from django.templatetags.static import static
 
-from iommi._db_compat import field_defaults_factory
+from iommi._db_compat import (
+    choices_from_model_field,
+    field_defaults_factory,
+)
 from iommi._web_compat import (
     csrf,
     format_html,
@@ -1517,7 +1520,7 @@ def foreign_key(cls, model_field, model, **kwargs):
         del model
         setdefaults_path(
             kwargs,
-            choices=model_field.foreign_related_fields[0].model.objects.all(),
+            choices=choices_from_model_field(model_field.foreign_related_fields[0].model, model_field),
         )
         return cls.choice_queryset(model_field=model_field, **kwargs)
 
@@ -1541,7 +1544,7 @@ def foreign_key_reverse(cls, *, model_field, **kwargs):
     def many_to_many(cls, model_field, **kwargs):
         setdefaults_path(
             kwargs,
-            choices=model_field.remote_field.model.objects.all(),
+            choices=choices_from_model_field(model_field.remote_field.model, model_field),
             read_from_instance=many_to_many_factory_read_from_instance,
             write_to_instance=many_to_many_factory_write_to_instance,
             extra__django_related_field=True,

iommi/form__tests.py

@@ -1591,6 +1591,47 @@ class MyForm(Form):
     assert set(choices) == set(Foo.objects.all())
 
 
+@pytest.mark.django_db
+def test_field_from_model_foreign_key_limit_choices_to():
+    from tests.models import Foo, LimitChoicesToFKTest
+
+    Foo.objects.create(foo=2)
+    b = Foo.objects.create(foo=3)
+    c = Foo.objects.create(foo=5)
+
+    class MyForm(Form):
+        foo_fk = Field.from_model(LimitChoicesToFKTest, 'foo_fk')
+
+    form = MyForm().bind(request=req('get'))
+    assert set(form.fields.foo_fk.choices) == {b, c}
+
+
+@pytest.mark.django_db
+def test_field_from_model_many_to_many_limit_choices_to():
+    from tests.models import Foo, LimitChoicesToM2MTest
+
+    Foo.objects.create(foo=2)
+    b = Foo.objects.create(foo=3)
+    c = Foo.objects.create(foo=5)
+
+    class MyForm(Form):
+        foo_m2m = Field.from_model(LimitChoicesToM2MTest, 'foo_m2m')
+
+    form = MyForm().bind(request=req('get'))
+    assert set(form.fields.foo_m2m.choices) == {b, c}
+
+
+@pytest.mark.django_db
+def test_field_from_model_foreign_key_to_proxy_model():
+    from tests.models import FKToFooProxyTest, Foo
+
+    class MyForm(Form):
+        foo_fk = Field.from_model(FKToFooProxyTest, 'foo_fk')
+
+    form = MyForm().bind(request=req('get'))
+    assert form.fields.foo_fk.choices.model is Foo
+
+
 @pytest.mark.django_db
 def test_field_from_model_many_to_many():
     from django.db.models import QuerySet

iommi/query.py

@@ -39,6 +39,7 @@
     ZeroOrMore
 )
 
+from iommi._db_compat import choices_from_model_field
 from iommi._web_compat import (
     render_template,
     Template,
@@ -546,7 +547,7 @@ def duration(cls, **kwargs):
     def foreign_key(cls, model_field, **kwargs):
         setdefaults_path(
             kwargs,
-            choices=model_field.foreign_related_fields[0].model.objects.all(),
+            choices=choices_from_model_field(model_field.foreign_related_fields[0].model, model_field),
         )
         return cls.choice_queryset(model_field=model_field, **kwargs)
 
@@ -569,7 +570,7 @@ def foreign_key_reverse(cls, *, model_field, **kwargs):
     def many_to_many(cls, model_field, **kwargs):
         setdefaults_path(
             kwargs,
-            choices=model_field.remote_field.model.objects.all(),
+            choices=choices_from_model_field(model_field.remote_field.model, model_field),
             extra__django_related_field=True,
         )
         return cls.multi_choice_queryset(model_field=model_field, **kwargs)

iommi/table.py

@@ -44,6 +44,7 @@
 )
 from django.utils.translation import gettext_lazy
 
+from iommi._db_compat import choices_from_model_field
 from iommi._web_compat import (
     HttpResponse,
     HttpResponseRedirect,
@@ -1008,7 +1009,7 @@ def duration(cls, **kwargs):
     def many_to_many(cls, model_field, **kwargs):
         setdefaults_path(
             kwargs,
-            choices=model_field.remote_field.model.objects.all(),
+            choices=choices_from_model_field(model_field.remote_field.model, model_field),
             model_field=model_field,
         )
         return cls.multi_choice_queryset(**kwargs)
@@ -1038,7 +1039,7 @@ def foreign_key(cls, model_field, **kwargs):
             )
         setdefaults_path(
             kwargs,
-            choices=remote_model.objects.all(),
+            choices=choices_from_model_field(remote_model, model_field),
         )
         return cls.choice_queryset(model_field=model_field, **kwargs)
 

tests/models.py

@@ -327,3 +327,20 @@ class UuidPKModel(Model):
 
 class AttachmentModel(Model):
     file = FileField(null=True)
+
+
+class LimitChoicesToFKTest(Model):
+    foo_fk = ForeignKey(Foo, on_delete=CASCADE, limit_choices_to={'foo__gte': 3})
+
+
+class LimitChoicesToM2MTest(Model):
+    foo_m2m = ManyToManyField(Foo, limit_choices_to={'foo__gte': 3})
+
+
+class FooProxy(Foo):
+    class Meta:
+        proxy = True
+
+
+class FKToFooProxyTest(Model):
+    foo_fk = ForeignKey(FooProxy, on_delete=CASCADE)