From 4ca64f2bd52dea691e33473dc97f8ee9e2a1130d Mon Sep 17 00:00:00 2001
From: Tim Graham <timograham@gmail.com>
Date: Tue, 29 May 2018 21:43:38 -0400
Subject: [PATCH] [2.1.x] Refs #28748 -- Reallowed lazy model field choices.
Regression in 3aa9ab39cce6b2a27d6334ad0148c8f37b6f5986.
Backport of c03e41712b2274f524d32bc2aef455ed82c9e3b4 from master
---
django/db/models/fields/__init__.py | 6 +++---
tests/invalid_models_tests/test_ordinary_fields.py | 7 +++++++
2 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/django/db/models/fields/__init__.py b/django/db/models/fields/__init__.py
index f21a6df7f7..50d22bef0c 100644
--- a/django/db/models/fields/__init__.py
+++ b/django/db/models/fields/__init__.py
@@ -244,10 +244,10 @@ class Field(RegisterLookupMixin):
if not self.choices:
return []
- def is_value(value):
- return isinstance(value, (str, Promise)) or not is_iterable(value)
+ def is_value(value, accept_promise=True):
+ return isinstance(value, (str, Promise) if accept_promise else str) or not is_iterable(value)
- if is_value(self.choices):
+ if is_value(self.choices, accept_promise=False):
return [
checks.Error(
"'choices' must be an iterable (e.g., a list or tuple).",
diff --git a/tests/invalid_models_tests/test_ordinary_fields.py b/tests/invalid_models_tests/test_ordinary_fields.py
index fb222edad3..546c16a976 100644
--- a/tests/invalid_models_tests/test_ordinary_fields.py
+++ b/tests/invalid_models_tests/test_ordinary_fields.py
@@ -4,6 +4,7 @@ from django.core.checks import Error, Warning as DjangoWarning
from django.db import connection, models
from django.test import SimpleTestCase, TestCase, skipIfDBFeature
from django.test.utils import isolate_apps, override_settings
+from django.utils.functional import lazy
from django.utils.timezone import now
from django.utils.translation import gettext_lazy as _
@@ -188,6 +189,12 @@ class CharFieldTests(TestCase):
self.assertEqual(Model._meta.get_field('field').check(), [])
+ def test_lazy_choices(self):
+ class Model(models.Model):
+ field = models.CharField(max_length=10, choices=lazy(lambda: [[1, '1'], [2, '2']], tuple)())
+
+ self.assertEqual(Model._meta.get_field('field').check(), [])
+
def test_choices_named_group(self):
class Model(models.Model):
field = models.CharField(