Push User.language choices callable to the model

as per the comment: possible from Django 5.0 up

users/forms.py

@@ -9,8 +9,7 @@ from django.core.exceptions import ValidationError
 from django.contrib.auth import password_validation
 from django.forms import ModelForm
 from django.utils.html import escape, mark_safe
-from django.utils.translation import gettext_lazy as _, get_language_info
+from django.utils.translation import gettext_lazy as _
-from django.conf import settings
 
 
 TRUE_FALSE_CHOICES = (
@@ -133,18 +132,6 @@ class SetPasswordForm(BaseSetPasswordForm):
         self.fields['new_password2'].help_text = None  # "Confirm password" is descriptive enough
 
 
-def language_choices():
-    items = [("auto", _("Auto (browser preference)"))]
-
-    for code, _label in settings.LANGUAGES:
-        info = get_language_info(code)
-        label = info["name_local"] \
-            if info["name_local"] == info["name_translated"] \
-            else f"{info['name_local']} ({info['name_translated']})"
-        items.append((code, label))
-    return items
-
-
 class PreferencesForm(ModelForm):
     # I haven't gotten a decent display for checkboxes in forms yet; the quickest hack around this is a ChoiceField
     send_email_alerts = forms.ChoiceField(
@@ -155,12 +142,6 @@ class PreferencesForm(ModelForm):
         required=True,
         widget=forms.Select(),
     )
-    language = forms.ChoiceField(
-        label=_("Language"),
-        choices=language_choices,
-        required=True,
-        widget=forms.Select(),
-    )
 
     class Meta:
         model = User

users/migrations/0004_alter_user_language.py

@@ -0,0 +1,19 @@
+import users.models
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("users", "0003_user_language"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="user",
+            name="language",
+            field=models.CharField(
+                choices=users.models.language_choices, default="auto", max_length=10
+            ),
+        ),
+    ]

users/models.py

@@ -3,7 +3,19 @@ import secrets
 from django.db import models
 from django.contrib.auth.models import AbstractUser
 from django.conf import settings
-from django.utils.translation import gettext_lazy as _
+from django.utils.translation import gettext_lazy as _, get_language_info
+
+
+def language_choices():
+    items = [("auto", _("Auto (browser preference)"))]
+
+    for code, _label in settings.LANGUAGES:
+        info = get_language_info(code)
+        label = info["name_local"] \
+            if info["name_local"] == info["name_translated"] \
+            else f"{info['name_local']} ({info['name_translated']})"
+        items.append((code, label))
+    return items
 
 
 class User(AbstractUser):
@@ -30,10 +42,9 @@ class User(AbstractUser):
         blank=False,
     )
     language = models.CharField(
+        _("Language"),
         max_length=10,
-        # choices intentionally not set, we don't want changes to trigger migrations; the actual choices are set in
+        choices=language_choices,
-        # forms.py; in Django 5.0 and up we can instead used a callable here
-        # choices=...
         default="auto",
         blank=False,
     )