Fixed #30439 - Translations issues on upgrade due to unexpected changes in plural forms

AUTHORS

@@ -766,6 +766,7 @@ answer newbie questions, and generally made Django that much better:
     Rob Hudson <https://rob.cogit8.org/>
     Rob Nguyen <tienrobertnguyenn@gmail.com>
     Robin Munn <http://www.geekforgod.com/>
+    Rodrigo Gadea <matematica.a3k@gmail.com>
     Rodrigo Pinheiro Marques de Araújo <fenrrir@gmail.com>
     Romain Garrigues <romain.garrigues.cs@gmail.com>
     Ronny Haryanto <https://ronny.haryan.to/>

django/conf/global_settings.py

@@ -151,6 +151,11 @@ def gettext_noop(s):
 USE_I18N = True
 LOCALE_PATHS = []
 
+# If you set this to True, Django will issue a warning when merging a message
+# file for translations with different plural forms than the main ones of the
+# locale.
+PLURAL_FORMS_CONSISTENCY = False
+
 # Settings for language cookie
 LANGUAGE_COOKIE_NAME = 'django_language'
 LANGUAGE_COOKIE_AGE = None

django/contrib/admin/locale/en/LC_MESSAGES/djangojs.po

@@ -12,6 +12,7 @@ msgstr ""
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
+"Plural-Forms: nplurals=2; plural=(n != 1);\n"
 
 #: contrib/admin/static/admin/js/SelectFilter2.js:47
 #, javascript-format

django/contrib/admin/locale/kn/LC_MESSAGES/django.po

@@ -15,7 +15,7 @@ msgstr ""
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
 "Language: kn\n"
-"Plural-Forms: nplurals=1; plural=0;\n"
+"Plural-Forms: nplurals=2; plural=(n > 1);\n"
 
 #, python-format
 msgid "Successfully deleted %(count)d %(items)s."
@@ -221,11 +221,13 @@ msgstr "ದತ್ತಸಂಚಯದ ದೋಷ"
 msgid "%(count)s %(name)s was changed successfully."
 msgid_plural "%(count)s %(name)s were changed successfully."
 msgstr[0] ""
+msgstr[1] ""
 
 #, python-format
 msgid "%(total_count)s selected"
 msgid_plural "All %(total_count)s selected"
 msgstr[0] ""
+msgstr[1] ""
 
 #, python-format
 msgid "0 of %(cnt)s selected"
@@ -511,6 +513,7 @@ msgstr ""
 msgid "%(counter)s result"
 msgid_plural "%(counter)s results"
 msgstr[0] ""
+msgstr[1] ""
 
 #, python-format
 msgid "%(full_result_count)s total"

django/contrib/admin/locale/kn/LC_MESSAGES/djangojs.po

@@ -16,7 +16,7 @@ msgstr ""
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
 "Language: kn\n"
-"Plural-Forms: nplurals=1; plural=0;\n"
+"Plural-Forms: nplurals=2; plural=(n > 1);\n"
 
 #, javascript-format
 msgid "Available %s"
@@ -68,6 +68,7 @@ msgstr ""
 msgid "%(sel)s of %(cnt)s selected"
 msgid_plural "%(sel)s of %(cnt)s selected"
 msgstr[0] ""
+msgstr[1] ""
 
 msgid ""
 "You have unsaved changes on individual editable fields. If you run an "
@@ -92,11 +93,13 @@ msgstr ""
 msgid "Note: You are %s hour ahead of server time."
 msgid_plural "Note: You are %s hours ahead of server time."
 msgstr[0] ""
+msgstr[1] ""
 
 #, javascript-format
 msgid "Note: You are %s hour behind server time."
 msgid_plural "Note: You are %s hours behind server time."
 msgstr[0] ""
+msgstr[1] ""
 
 msgid "Now"
 msgstr "ಈಗ"