Fix #544 -- Ensure correct attribute defaults (#547)

dict.setdefault() does not change the default value if called twice.
Therefore, defaults need to passed to the super call instead.

Author: mfrasca

django_select2/forms.py

@@ -70,16 +70,18 @@ class Select2Mixin:
     form media.
     """
 
-    def build_attrs(self, *args, **kwargs):
+    def build_attrs(self, base_attrs, extra_attrs=None):
         """Add select2 data attributes."""
-        attrs = super(Select2Mixin, self).build_attrs(*args, **kwargs)
+        default_attrs = {'data-minimum-input-length': 0}
         if self.is_required:
-            attrs.setdefault('data-allow-clear', 'false')
+            default_attrs['data-allow-clear'] = 'false'
         else:
-            attrs.setdefault('data-allow-clear', 'true')
-            attrs.setdefault('data-placeholder', '')
+            default_attrs['data-allow-clear'] = 'true'
+            default_attrs['data-placeholder'] = ''
+
+        default_attrs.update(base_attrs)
+        attrs = super().build_attrs(default_attrs, extra_attrs=extra_attrs)
 
-        attrs.setdefault('data-minimum-input-length', 0)
         if 'class' in attrs:
             attrs['class'] += ' django-select2'
         else:
@@ -120,12 +122,15 @@ def _get_media(self):
 class Select2TagMixin:
     """Mixin to add select2 tag functionality."""
 
-    def build_attrs(self, *args, **kwargs):
+    def build_attrs(self, base_attrs, extra_attrs=None):
         """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(*args, **kwargs)
+        default_attrs = {
+            'data-minimum-input-length': 1,
+            'data-tags': 'true',
+            'data-token-separators': '[",", " "]'
+        }
+        default_attrs.update(base_attrs)
+        return super().build_attrs(default_attrs, extra_attrs=extra_attrs)
 
 
 class Select2Widget(Select2Mixin, forms.Select):
@@ -226,20 +231,27 @@ def get_url(self):
             return self.data_url
         return reverse(self.data_view)
 
-    def build_attrs(self, *args, **kwargs):
+    def build_attrs(self, base_attrs, extra_attrs=None):
         """Set select2's AJAX attributes."""
-        attrs = super(HeavySelect2Mixin, self).build_attrs(*args, **kwargs)
+
+        default_attrs = {
+            'data-ajax--url': self.get_url(),
+            'data-ajax--cache': "true",
+            'data-ajax--type': "GET",
+            'data-minimum-input-length': 2,
+        }
+
+        if self.dependent_fields:
+            default_attrs['data-select2-dependent-fields'] = " ".join(self.dependent_fields)
+
+        default_attrs.update(base_attrs)
+
+        attrs = super().build_attrs(default_attrs, extra_attrs=extra_attrs)
 
         # encrypt instance Id
         self.widget_id = signing.dumps(id(self))
 
         attrs['data-field_id'] = self.widget_id
-        attrs.setdefault('data-ajax--url', self.get_url())
-        attrs.setdefault('data-ajax--cache', "true")
-        attrs.setdefault('data-ajax--type', "GET")
-        attrs.setdefault('data-minimum-input-length', 2)
-        if self.dependent_fields:
-            attrs.setdefault('data-select2-dependent-fields', " ".join(self.dependent_fields))
 
         attrs['class'] += ' django-select2-heavy'
         return attrs

tests/conftest.py

@@ -2,7 +2,6 @@
 import string
 
 import pytest
-from django.utils.encoding import force_text
 from selenium import webdriver
 from selenium.common.exceptions import WebDriverException
 
@@ -22,11 +21,11 @@ def random_name(n):
 @pytest.yield_fixture(scope='session')
 def driver():
     chrome_options = webdriver.ChromeOptions()
-    chrome_options.headless = True
+    chrome_options.headless = False
     try:
         b = webdriver.Chrome(options=chrome_options)
     except WebDriverException as e:
-        pytest.skip(force_text(e))
+        pytest.skip(str(e))
     else:
         yield b
         b.quit()

tests/test_forms.py

@@ -217,12 +217,17 @@ def test_multiple_widgets(self, db, live_server, driver):
             driver.find_element_by_css_selector('.select2-results')
 
         elem1, elem2 = driver.find_elements_by_css_selector('.select2-selection')
-        elem1.click()
 
+        elem1.click()
+        search1 = driver.find_element_by_css_selector('.select2-search__field')
+        search1.send_keys('fo')
         result1 = WebDriverWait(driver, 60).until(
             expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li:first-child'))
         ).text
+
         elem2.click()
+        search2 = driver.find_element_by_css_selector('.select2-search__field')
+        search2.send_keys('fo')
         result2 = WebDriverWait(driver, 60).until(
             expected_conditions.presence_of_element_located((By.CSS_SELECTOR, '.select2-results li:first-child'))
         ).text
@@ -315,6 +320,37 @@ def test_get_queryset(self):
         widget.queryset = Genre.objects.all()
         assert isinstance(widget.get_queryset(), QuerySet)
 
+    def test_tag_attrs_Select2Widget(self):
+        widget = Select2Widget()
+        output = widget.render('name', 'value')
+        assert 'data-minimum-input-length="0"' in output
+
+    def test_custom_tag_attrs_Select2Widget(self):
+        widget = Select2Widget(attrs={'data-minimum-input-length': '3'})
+        output = widget.render('name', 'value')
+        assert 'data-minimum-input-length="3"' in output
+
+    def test_tag_attrs_ModelSelect2Widget(self):
+        widget = ModelSelect2Widget(queryset=Genre.objects.all(), search_fields=['title__icontains'])
+        output = widget.render('name', 'value')
+        assert 'data-minimum-input-length="2"' in output
+
+    def test_tag_attrs_ModelSelect2TagWidget(self):
+        widget = ModelSelect2TagWidget(queryset=Genre.objects.all(), search_fields=['title__icontains'])
+        output = widget.render('name', 'value')
+        assert 'data-minimum-input-length="2"' in output
+
+    def test_tag_attrs_HeavySelect2Widget(self):
+        widget = HeavySelect2Widget(data_url='/foo/bar/')
+        output = widget.render('name', 'value')
+        assert 'data-minimum-input-length="2"' in output
+
+    def test_custom_tag_attrs_ModelSelect2Widget(self):
+        widget = ModelSelect2Widget(
+            queryset=Genre.objects.all(), search_fields=['title__icontains'], attrs={'data-minimum-input-length': '3'})
+        output = widget.render('name', 'value')
+        assert 'data-minimum-input-length="3"' in output
+
     def test_get_search_fields(self):
         widget = ModelSelect2Widget()
         with pytest.raises(NotImplementedError):
@@ -382,7 +418,7 @@ class TestHeavySelect2TagWidget(TestHeavySelect2Mixin):
     def test_tag_attrs(self):
         widget = ModelSelect2TagWidget(queryset=Genre.objects.all(), search_fields=['title__icontains'])
         output = widget.render('name', 'value')
-        assert 'data-minimum-input-length="1"' in output
+        assert 'data-minimum-input-length="2"' in output
         assert 'data-tags="true"' in output
         assert 'data-token-separators' in output
 

tests/testapp/forms.py

@@ -149,11 +149,19 @@ class HeavySelect2WidgetForm(forms.Form):
 class HeavySelect2MultipleWidgetForm(forms.Form):
     title = forms.CharField(max_length=50)
     genres = forms.MultipleChoiceField(
-        widget=HeavySelect2MultipleWidget(data_view='heavy_data_1', choices=NUMBER_CHOICES),
+        widget=HeavySelect2MultipleWidget(
+            data_view='heavy_data_1',
+            choices=NUMBER_CHOICES,
+            attrs={'data-minimum-input-length': 0},
+        ),
         choices=NUMBER_CHOICES
     )
     featured_artists = forms.MultipleChoiceField(
-        widget=HeavySelect2MultipleWidget(data_view='heavy_data_2', choices=NUMBER_CHOICES),
+        widget=HeavySelect2MultipleWidget(
+            data_view='heavy_data_2',
+            choices=NUMBER_CHOICES,
+            attrs={'data-minimum-input-length': 0},
+        ),
         choices=NUMBER_CHOICES,
         required=False
     )
@@ -182,6 +190,7 @@ class AddressChainedSelect2WidgetForm(forms.Form):
             search_fields=['name__icontains'],
             max_results=500,
             dependent_fields={'city': 'cities'},
+            attrs={'data-minimum-input-length': 0},
         )
     )
 
@@ -193,6 +202,7 @@ class AddressChainedSelect2WidgetForm(forms.Form):
             search_fields=['name__icontains'],
             dependent_fields={'country': 'country'},
             max_results=500,
+            attrs={'data-minimum-input-length': 0},
         )
     )