[Django 4.1+] Make i18n works for LANGUAGE_CODE with a country code

CONTRIBUTING.rst

@@ -13,7 +13,7 @@ To install the package and its dependencies for development
 including tests dependencies, please do:
 
     python -m pip install -e .[test]
-    
+
 You may ran the tests via::
 
     python -m pytest

django_select2/forms.py

@@ -54,12 +54,11 @@
 
 import django
 from django import forms
-from django.contrib.admin.widgets import SELECT2_TRANSLATIONS, AutocompleteMixin
+from django.contrib.admin.widgets import AutocompleteMixin
 from django.core import signing
 from django.db.models import Q
 from django.forms.models import ModelChoiceIterator
 from django.urls import reverse
-from django.utils.translation import get_language
 
 from .cache import cache
 from .conf import settings
@@ -89,7 +88,15 @@ class Select2Mixin:
     @property
     def i18n_name(self):
         """Name of the i18n file for the current language."""
-        return SELECT2_TRANSLATIONS.get(get_language())
+        if django.VERSION < (4, 1):
+            from django.contrib.admin.widgets import SELECT2_TRANSLATIONS
+            from django.utils.translation import get_language
+
+            return SELECT2_TRANSLATIONS.get(get_language())
+        else:
+            from django.contrib.admin.widgets import get_select2_language
+
+            return get_select2_language()
 
     def build_attrs(self, base_attrs, extra_attrs=None):
         """Add select2 data attributes."""
@@ -258,7 +265,7 @@ def __init__(self, attrs=None, choices=(), **kwargs):
         if dependent_fields is not None:
             self.dependent_fields = dict(dependent_fields)
         if not (self.data_view or self.data_url):
-            raise ValueError('You must ether specify "data_view" or "data_url".')
+            raise ValueError('You must either specify "data_view" or "data_url".')
         self.userGetValTextFuncName = kwargs.pop("userGetValTextFuncName", "null")
 
     def get_url(self):

tests/test_forms.py

@@ -2,6 +2,7 @@
 import os
 from collections.abc import Iterable
 
+import django
 import pytest
 from django.db.models import QuerySet
 from django.urls import reverse
@@ -822,3 +823,73 @@ def test_dependent_fields_clear_after_change_parent(
             )
         )
         assert city2_container.text == ""
+
+
+@pytest.fixture(
+    name="widget",
+    params=[
+        (Select2Widget, {}),
+        (HeavySelect2Widget, {"data_view": "heavy_data_1"}),
+        (HeavySelect2MultipleWidget, {"data_view": "heavy_data_1"}),
+        (ModelSelect2Widget, {}),
+        (ModelSelect2TagWidget, {}),
+    ],
+    ids=lambda p: p[0],
+)
+def widget_fixture(request):
+    widget_class, widget_kwargs = request.param
+    return widget_class(**widget_kwargs)
+
+
+@pytest.mark.skipif(django.VERSION < (4, 1), reason="Only for Django 4.1+")
+@pytest.mark.parametrize(
+    "locale,expected",
+    [
+        ("fr-FR", "fr"),
+        # Some locales with a country code are natively supported by select2's i18n
+        ("pt-BR", "pt-BR"),
+        ("sr-Cyrl", "sr-Cyrl"),
+    ],
+    ids=repr,
+)
+def test_i18n_name_property_with_country_code_in_locale(widget, locale, expected):
+    """Test we fall back to the language code if the locale contain an unsupported country code."""
+    with translation.override(locale):
+        assert widget.i18n_name == expected
+
+
+@pytest.mark.skipif(django.VERSION < (4, 1), reason="Only for Django 4.1+")
+def test_i18n_media_js_with_country_code_in_locale(widget):
+    translation.activate("fr-FR")
+    assert tuple(widget.media._js) == (
+        "admin/js/vendor/select2/select2.full.min.js",
+        "admin/js/vendor/select2/i18n/fr.js",
+        "django_select2/django_select2.js",
+    )
+
+
+@pytest.mark.skipif(django.VERSION >= (4, 1), reason="Only for Django 4.0 and previous")
+@pytest.mark.parametrize(
+    "locale,expected",
+    [
+        ("fr-FR", None),
+        # Some locales with a country code are natively supported by select2's i18n
+        ("pt-BR", "pt-BR"),
+        ("sr-Cyrl", "sr-Cyrl"),
+    ],
+)
+def test_i18n_name_property_with_country_code_in_locale_for_older_django(
+    widget, locale, expected
+):
+    """No fallback for locale with an unsupported country code."""
+    with translation.override(locale):
+        assert widget.i18n_name == expected
+
+
+@pytest.mark.skipif(django.VERSION >= (4, 1), reason="Only for Django 4.0 and previous")
+def test_i18n_media_js_with_country_code_in_locale_for_older_django(widget):
+    translation.activate("fr-FR")
+    assert tuple(widget.media._js) == (
+        "admin/js/vendor/select2/select2.full.min.js",
+        "django_select2/django_select2.js",
+    )