Fixed #222 -- Display intital data for heavy widgets

Patched ciritcal memory leak in ModelSelect2 widgets.
Boolean evaluation of queryset makes django fetch all
elements.

Thanks to @magicjohnson for discovering this issue

CHANGELOG.md

@@ -1,6 +1,15 @@
 Changelog Summary
 =================
 
+### v5.4.2
+* Fixed initial data not being shown for heavy widgets.
+
+### v5.4.1
+* Fixed memory leak in `ModelSelect2Mixin` and subclasses
+
+### v5.4.0
+* Added `Select2TagWidget` a light widget with tagging support
+
 ### v5.3.0
 * Added djangoSelect2 jQuery plugin to support
   dynamic field initialisation

django_select2/__init__.py

@@ -9,4 +9,4 @@ The app includes Select2 driven Django Widgets and Form Fields.
 
 """
 
-__version__ = "5.3.1"
+__version__ = "5.4.2"

django_select2/forms.py

@@ -49,6 +49,7 @@ Light widgets are normally named, i.e. there is no
 from __future__ import absolute_import, unicode_literals
 
 from functools import reduce
+from itertools import chain
 
 from django import forms
 from django.core import signing
@@ -109,6 +110,18 @@ class Select2Mixin(object):
     media = property(_get_media)
 
 
+class Select2TagMixin(object):
+
+    """Mixin to add select2 tag functionality."""
+
+    def build_attrs(self, extra_attrs=None, **kwargs):
+        """Add select2's tag attributes."""
+        self.attrs.setdefault('data-minimum-input-length', 1)
+        self.attrs.setdefault('data-tags', 'true')
+        self.attrs.setdefault('data-token-separators', [",", " "])
+        return super(Select2TagMixin, self).build_attrs(extra_attrs, **kwargs)
+
+
 class Select2Widget(Select2Mixin, forms.Select):
 
     """
@@ -145,6 +158,24 @@ class Select2MultipleWidget(Select2Mixin, forms.SelectMultiple):
     pass
 
 
+class Select2TagWidget(Select2TagMixin, Select2Mixin, forms.SelectMultiple):
+
+    """
+    Select2 drop in widget for for tagging.
+
+    Example for :class:`.django.contrib.postgres.fields.ArrayField`::
+
+        class MyWidget(Select2TagWidget):
+
+            def value_from_datadict(self, data, files, name):
+                values = super(MyWidget, self).value_from_datadict(data, files, name):
+                return ",".join(values)
+
+    """
+
+    pass
+
+
 class HeavySelect2Mixin(Select2Mixin):
 
     """Mixin that adds select2's ajax options and registers itself on django's cache."""
@@ -203,6 +234,7 @@ class HeavySelect2Mixin(Select2Mixin):
 
     def render_options(self, choices, selected_choices):
         """Render only selected options."""
+        choices = chain(choices, self.choices)
         output = ['<option></option>' if not self.is_required else '']
         choices = {(k, v) for k, v in choices if k in selected_choices}
         selected_choices = {force_text(v) for v in selected_choices}
@@ -242,16 +274,11 @@ class HeavySelect2MultipleWidget(HeavySelect2Mixin, forms.SelectMultiple):
     pass
 
 
-class HeavySelect2TagWidget(HeavySelect2MultipleWidget):
+class HeavySelect2TagWidget(Select2TagMixin, HeavySelect2MultipleWidget):
 
-    """Mixin to add select2 tag functionality."""
+    """Select2 tag widget."""
 
-    def build_attrs(self, extra_attrs=None, **kwargs):
-        """Add select2's tag attributes."""
-        self.attrs.setdefault('data-minimum-input-length', 1)
-        self.attrs.setdefault('data-tags', 'true')
-        self.attrs.setdefault('data-token-separators', [",", " "])
-        return super(HeavySelect2TagWidget, self).build_attrs(extra_attrs, **kwargs)
+    pass
 
 
 # Auto Heavy widgets
@@ -326,7 +353,7 @@ class ModelSelect2Mixin(object):
         :return: Filtered queryset
         :rtype: :class:`.django.db.models.QuerySet`
         """
-        if not queryset:
+        if queryset is None:
             queryset = self.get_queryset()
         search_fields = self.get_search_fields()
         select = Q()
@@ -375,6 +402,7 @@ class ModelSelect2Mixin(object):
             choices = {self.choices.choice(obj)
                        for obj in self.choices.queryset.filter(pk__in=selected_choices)}
         else:
+            choices = chain(choices, self.choices)
             choices = {(k, v) for k, v in choices if k in selected_choices}
         selected_choices = {force_text(v) for v in selected_choices}
         for option_value, option_label in choices:
@@ -391,7 +419,7 @@ class ModelSelect2Widget(ModelSelect2Mixin, HeavySelect2Widget):
 
         class MyWidget(ModelSelect2Widget):
             search_fields = [
-                'title__icontians',
+                'title__icontains',
             ]
 
         class MyModelForm(forms.ModelForm):
@@ -432,10 +460,10 @@ class ModelSelect2MultipleWidget(ModelSelect2Mixin, HeavySelect2MultipleWidget):
     pass
 
 
-class ModelSelect2TagWidget(ModelSelect2Mixin, HeavySelect2TagWidget):
+class ModelSelect2TagWidget(Select2TagMixin, ModelSelect2MultipleWidget):
 
     """
-    Select2 model field with tag support.
+    Select2 model widget with tag support.
 
     This it not a simple drop in widget.
     It requires to implement you own :func:`.value_from_datadict`
@@ -447,7 +475,7 @@ class ModelSelect2TagWidget(ModelSelect2Mixin, HeavySelect2TagWidget):
             queryset = MyModel.objects.all()
 
             def value_from_datadict(self, data, files, name):
-                values = super().value_from_datadict(self, data, files, name):
+                values = super().value_from_datadict(self, data, files, name)
                 qs = self.queryset.filter(**{'pk__in': list(values)})
                 pks = set(force_text(getattr(o, pk)) for o in qs)
                 cleaned_values = []

tests/test_forms.py

@@ -30,6 +30,11 @@ class TestSelect2Mixin(object):
     form = forms.AlbumSelect2WidgetForm()
     widget_cls = Select2Widget
 
+    def test_initial_data(self, genres):
+        genre = genres[0]
+        form = self.form.__class__(initial={'primary_genre': genre.pk})
+        assert text_type(genre) in form.as_p()
+
     def test_initial_form_class(self):
         widget = self.widget_cls(attrs={'class': 'my-class'})
         assert 'my-class' in widget.render('name', None)
@@ -81,9 +86,12 @@ class TestSelect2Mixin(object):
 
 class TestHeavySelect2Mixin(TestSelect2Mixin):
     url = reverse('heavy_select2_widget')
-    form = forms.HeavySelect2WidgetForm(initial={'primary_genre': [1]})
+    form = forms.HeavySelect2WidgetForm(initial={'primary_genre': 1})
     widget_cls = HeavySelect2Widget
 
+    def test_initial_data(self):
+        assert 'One' in self.form.as_p()
+
     def test_initial_form_class(self):
         widget = self.widget_cls(data_view='heavy_data_1', attrs={'class': 'my-class'})
         assert 'my-class' in widget.render('name', None)
@@ -129,6 +137,11 @@ class TestHeavySelect2Mixin(TestSelect2Mixin):
 class TestModelSelect2Mixin(TestHeavySelect2Mixin):
     form = forms.AlbumModelSelect2WidgetForm(initial={'primary_genre': 1})
 
+    def test_initial_data(self, genres):
+        genre = genres[0]
+        form = self.form.__class__(initial={'primary_genre': genre.pk})
+        assert text_type(genre) in form.as_p()
+
     @pytest.fixture(autouse=True)
     def genres(self, db):
         return mommy.make(Genre, 100)

tests/testapp/forms.py

@@ -114,11 +114,13 @@ class Select2WidgetForm(forms.Form):
 
 class HeavySelect2WidgetForm(forms.Form):
     artist = forms.ChoiceField(
-        widget=HeavySelect2Widget(data_view='heavy_data_1', choices=NUMBER_CHOICES)
+        widget=HeavySelect2Widget(data_view='heavy_data_1'),
+        choices=NUMBER_CHOICES
     )
     primary_genre = forms.ChoiceField(
-        widget=HeavySelect2Widget(data_view='heavy_data_2', choices=NUMBER_CHOICES),
-        required=False
+        widget=HeavySelect2Widget(data_view='heavy_data_2'),
+        required=False,
+        choices=NUMBER_CHOICES
     )