Fixes #256 -- Don't render empty option for multiselect (#275)

django_select2/forms.py

@@ -92,7 +92,7 @@ class Select2Mixin(object):
 
     def render_options(self, *args, **kwargs):
         """Render options including an empty one, if the field is not required."""
-        output = '<option></option>' if not self.is_required else ''
+        output = '<option></option>' if not self.is_required and not self.allow_multiple_selected else ''
         output += super(Select2Mixin, self).render_options(*args, **kwargs)
         return output
 
@@ -248,7 +248,7 @@ class HeavySelect2Mixin(object):
             choices = chain(self.choices, choices)
         else:
             choices = self.choices
-        output = ['<option></option>' if not self.is_required else '']
+        output = ['<option></option>' if not self.is_required and not self.allow_multiple_selected else '']
         selected_choices = {force_text(v) for v in selected_choices}
         choices = {(k, v) for k, v in choices if force_text(k) in selected_choices}
         for option_value, option_label in choices:
@@ -412,7 +412,7 @@ class ModelSelect2Mixin(object):
         else:
             choices = self.choices
         selected_choices = {force_text(v) for v in selected_choices}
-        output = ['<option></option>' if not self.is_required else '']
+        output = ['<option></option>' if not self.is_required and not self.allow_multiple_selected else '']
         if isinstance(self.choices, ModelChoiceIterator):
             if not self.queryset:
                 self.queryset = self.choices.queryset

tests/test_forms.py

@@ -27,6 +27,7 @@ from tests.testapp.models import Genre
 class TestSelect2Mixin(object):
     url = reverse('select2_widget')
     form = forms.AlbumSelect2WidgetForm()
+    multiple_form = forms.AlbumSelect2MultipleWidgetForm()
     widget_cls = Select2Widget
 
     def test_initial_data(self, genres):
@@ -82,6 +83,18 @@ class TestSelect2Mixin(object):
         widget = HeavySelect2Widget(data_url='/foo/bar')
         assert widget.get_url() == '/foo/bar'
 
+    def test_empty_option(self, db):
+        # Empty options is only required for single selects
+        # https://select2.github.io/options.html#allowClear
+        single_select = self.form.fields['primary_genre']
+        assert single_select.required is False
+        assert '<option></option>' in single_select.widget.render('primary_genre', None)
+
+        multiple_select = self.multiple_form.fields['featured_artists']
+        assert multiple_select.required is False
+        assert multiple_select.widget.allow_multiple_selected
+        assert '<option></option>' not in multiple_select.widget.render('featured_artists', None)
+
 
 class TestSelect2MixinSettings(object):
     def test_default_media(self):
@@ -170,6 +183,7 @@ class TestHeavySelect2Mixin(TestSelect2Mixin):
 
 class TestModelSelect2Mixin(TestHeavySelect2Mixin):
     form = forms.AlbumModelSelect2WidgetForm(initial={'primary_genre': 1})
+    multiple_form = forms.ArtistModelSelect2MultipleWidgetForm()
 
     def test_initial_data(self, genres):
         genre = genres[0]

tests/testapp/forms.py

@@ -117,7 +117,12 @@ class ArtistModelSelect2MultipleWidgetForm(forms.Form):
     genres = forms.ModelMultipleChoiceField(widget=ModelSelect2MultipleWidget(
         queryset=models.Genre.objects.all(),
         search_fields=['title__icontains'],
-    ), queryset=models.Genre.objects.all(), required=False)
+    ), queryset=models.Genre.objects.all(), required=True)
+
+    featured_artists = forms.ModelMultipleChoiceField(widget=ModelSelect2MultipleWidget(
+        queryset=models.Artist.objects.all(),
+        search_fields=['title__icontains'],
+    ), queryset=models.Artist.objects.all(), required=False)
 
 NUMBER_CHOICES = [
     (1, 'One'),