Fixed prepopulated fields only work on the first defined field and made function aware of the current language. Added a unittest to verify. Resolves issue #57.

modeltranslation/admin.py

@@ -11,7 +11,8 @@ from django.contrib.contenttypes import generic
 import modeltranslation.models  # NOQA
 from modeltranslation.settings import DEFAULT_LANGUAGE
 from modeltranslation.translator import translator
-from modeltranslation.utils import get_translation_fields, build_css_class
+from modeltranslation.utils import (
+    get_translation_fields, build_css_class, build_localized_fieldname, get_language)
 
 
 class TranslationBaseModelAdmin(BaseModelAdmin):
@@ -129,11 +130,15 @@ class TranslationBaseModelAdmin(BaseModelAdmin):
 
     def _patch_prepopulated_fields(self):
         if self.prepopulated_fields:
+            # TODO: Perhaps allow to configure which language the slug should be based on?
+            lang = get_language()
             prepopulated_fields_new = dict(self.prepopulated_fields)
-            for (k, v) in self.prepopulated_fields.items():
-                if v[0] in self.trans_opts.fields:
-                    translation_fields = get_translation_fields(v[0])
-                    prepopulated_fields_new[k] = tuple([translation_fields[0]])
+            translation_fields = []
+            for k, v in self.prepopulated_fields.items():
+                for i in v:
+                    if i in self.trans_opts.fields.keys():
+                        translation_fields.append(build_localized_fieldname(i, lang))
+                prepopulated_fields_new[k] = tuple(translation_fields)
             self.prepopulated_fields = prepopulated_fields_new
 
     def _do_get_form_or_formset(self, request, obj, **kwargs):

modeltranslation/tests/__init__.py

@@ -227,7 +227,7 @@ class ModeltranslationTest(ModeltranslationTestBase):
         self.failUnless(translator.translator)
 
         # Check that all models are registered for translation
-        self.assertEqual(len(translator.translator.get_registered_models()), 20)
+        self.assertEqual(len(translator.translator.get_registered_models()), 21)
 
         # Try to unregister a model that is not registered
         self.assertRaises(translator.NotRegistered,
@@ -1615,6 +1615,33 @@ class TranslationAdminTest(ModeltranslationTestBase):
         self.assertEqual(ma.get_fieldsets(request), fieldsets)
         self.assertEqual(ma.get_fieldsets(request, self.test_obj), fieldsets)
 
+    def test_prepopulated_fields(self):
+        trans_real.activate('de')
+        self.failUnlessEqual(get_language(), 'de')
+
+        class NameModelAdmin(admin.TranslationAdmin):
+            prepopulated_fields = {'slug': ('firstname',)}
+        ma = NameModelAdmin(models.NameModel, self.site)
+        self.assertEqual(ma.prepopulated_fields, {'slug': ('firstname_de',)})
+
+        class NameModelAdmin(admin.TranslationAdmin):
+            prepopulated_fields = {'slug': ('firstname', 'lastname',)}
+        ma = NameModelAdmin(models.NameModel, self.site)
+        self.assertEqual(ma.prepopulated_fields, {'slug': ('firstname_de', 'lastname_de',)})
+
+        trans_real.activate('en')
+        self.failUnlessEqual(get_language(), 'en')
+
+        class NameModelAdmin(admin.TranslationAdmin):
+            prepopulated_fields = {'slug': ('firstname',)}
+        ma = NameModelAdmin(models.NameModel, self.site)
+        self.assertEqual(ma.prepopulated_fields, {'slug': ('firstname_en',)})
+
+        class NameModelAdmin(admin.TranslationAdmin):
+            prepopulated_fields = {'slug': ('firstname', 'lastname',)}
+        ma = NameModelAdmin(models.NameModel, self.site)
+        self.assertEqual(ma.prepopulated_fields, {'slug': ('firstname_en', 'lastname_en',)})
+
 
 class TestManager(ModeltranslationTestBase):
     def setUp(self):

modeltranslation/tests/models.py

@@ -140,6 +140,12 @@ class GroupFieldsetsModel(models.Model):
     email = models.EmailField(blank=True, null=True)
 
 
+class NameModel(models.Model):
+    firstname = models.CharField(max_length=50)
+    lastname = models.CharField(max_length=50)
+    slug = models.SlugField(max_length=100)
+
+
 ########## Manager testing
 
 class ManagerTestModel(models.Model):

modeltranslation/tests/translation.py

@@ -6,7 +6,7 @@ from modeltranslation.tests.models import (
     TestModel, FallbackModel, FallbackModel2, FileFieldsModel, OtherFieldsModel, AbstractModelA,
     AbstractModelB, Slugged, MetaData, Displayable, Page, RichText, RichTextPage,
     MultitableModelA, MultitableModelB, MultitableModelC, ManagerTestModel, CustomManagerTestModel,
-    CustomManager2TestModel, GroupFieldsetsModel)
+    CustomManager2TestModel, GroupFieldsetsModel, NameModel)
 
 
 class TestTranslationOptions(TranslationOptions):
@@ -142,3 +142,8 @@ class FieldInheritanceETranslationOptions(FieldInheritanceCTranslationOptions,
 class GroupFieldsetsTranslationOptions(TranslationOptions):
     fields = ('title', 'text',)
 translator.register(GroupFieldsetsModel, GroupFieldsetsTranslationOptions)
+
+
+class NameTranslationOptions(TranslationOptions):
+    fields = ('firstname', 'lastname',)
+translator.register(NameModel, NameTranslationOptions)