Add custom ModelForm class that supports field choice sorting. Use the new form class to sort the user profile language field and the document language fields. Thanks to Baptiste GAILLET @bat79a for the original idea. GitLab issue #292.

mayan/apps/common/forms.py

@@ -1,5 +1,6 @@
 from __future__ import unicode_literals
 
+from operator import itemgetter
 import os
 
 from django import forms
@@ -114,10 +115,44 @@ class LicenseForm(FileDisplayForm):
     FILENAME = 'LICENSE'
 
 
-class LocaleProfileForm(forms.ModelForm):
+class ModelForm(forms.ModelForm):
+    """
+    ModelForm subclass that supports field choices sorting
+
+    class Meta:
+        # Dictionary of field names and the key used to sort the field
+        sorted_fields = None
+
+    # Example:
+    # sorted_fields = {'language': operator.itemgetter(1))}
+    """
+
+    def __init__(self, *args, **kwargs):
+        super(ModelForm, self).__init__(*args, **kwargs)
+
+        for field, key in getattr(self.Meta, 'sorted_fields', {}).items():
+            # Would be the cleaner "opts.sorted_fields" if these were addressed
+            # https://code.djangoproject.com/ticket/5793
+            # of a get_options_class for Forms/ModelForms
+            # https://code.djangoproject.com/ticket/18540
+            choices = self.fields[field].choices
+
+            if not self.fields[field].required:
+                # Remove empty choice before sorting
+                empty_choice = choices.pop(0)
+
+            self.fields[field].choices = sorted(choices, key=key)
+
+            if not self.fields[field].required:
+                # Add empty choice after sorting
+                self.fields[field].choices.insert(0, empty_choice)
+
+
+class LocaleProfileForm(ModelForm):
     class Meta:
         fields = ('language', 'timezone')
         model = UserLocaleProfile
+        sorted_fields = {'language': itemgetter(1)}
 
 
 class LocaleProfileForm_view(DetailForm):