Handle invalid locale

src/backend/InvenTree/InvenTree/format.py

@@ -5,10 +5,12 @@ import string
 from typing import Optional
 
 from django.conf import settings
+from django.core.exceptions import ValidationError
 from django.utils import translation
 from django.utils.translation import gettext_lazy as _
 
 from babel import Locale
+from babel.core import UnknownLocaleError
 from babel.numbers import parse_pattern
 from djmoney.money import Money
 
@@ -205,7 +207,10 @@ def format_money(
         ValueError: format string is incorrectly specified
     """
     language = locale or settings.LANGUAGE_CODE
-    locale = Locale.parse(translation.to_locale(language))
+    try:
+        locale = Locale.parse(translation.to_locale(language))
+    except (UnknownLocaleError, ValueError) as e:
+        raise ValidationError(f"format_money: Invalid locale '{language}' - {e}")
 
     if fmt:
         pattern = parse_pattern(fmt)

src/backend/InvenTree/report/test_tags.py

@@ -571,6 +571,10 @@ class ReportTagTest(PartImageTestMixin, InvenTreeTestCase):
                 report_tags.render_currency(m, locale='en-us'), '$1,234.56'
             )
 
+        # Invalid locale raises ValidationError
+        with self.assertRaises(ValidationError):
+            report_tags.render_currency(m, locale='xx-zz')
+
     def test_create_currency(self):
         """Test the create_currency template tag."""
         m = report_tags.create_currency(1000, 'USD')