Disallow threads with space-only tags

boards/forms.py

@@ -214,13 +214,12 b' class ThreadForm(PostForm):'
 
     tags = forms.CharField(
         widget=forms.TextInput(attrs={ATTRIBUTE_PLACEHOLDER: TAGS_PLACEHOLDER}),
-        max_length=100, label=_('Tags'))
+        max_length=100, label=_('Tags'), required=True)
 
     def clean_tags(self):
         tags = self.cleaned_data['tags'].strip()
 
-        if tags:
-            if not self.regex_tags.match(tags):
+        if not tags or not self.regex_tags.match(tags):
                 raise forms.ValidationError(
                     _('Inappropriate characters in tags.'))