Fixed #17922 -- Added required_css_class to form label.

Thanks hanson2010 for the suggestion.

django/forms/forms.py

@@ -621,6 +621,12 @@ class BoundField(object):
             id_for_label = widget.id_for_label(id_)
             if id_for_label:
                 attrs = dict(attrs or {}, **{'for': id_for_label})
+            if self.field.required and hasattr(self.form, 'required_css_class'):
+                attrs = attrs or {}
+                if 'class' in attrs:
+                    attrs['class'] += ' ' + self.form.required_css_class
+                else:
+                    attrs['class'] = self.form.required_css_class
             attrs = flatatt(attrs) if attrs else ''
             contents = format_html('<label{0}>{1}</label>', attrs, contents)
         else:

docs/ref/forms/api.txt

@@ -511,10 +511,19 @@ classes, as needed. The HTML will look something like::
 
     >>> f = ContactForm(data)
     >>> print(f.as_table())
-    <tr class="required"><th><label for="id_subject">Subject:</label>    ...
-    <tr class="required"><th><label for="id_message">Message:</label>    ...
-    <tr class="required error"><th><label for="id_sender">Sender:</label>      ...
+    <tr class="required"><th><label class="required" for="id_subject">Subject:</label>    ...
+    <tr class="required"><th><label class="required" for="id_message">Message:</label>    ...
+    <tr class="required error"><th><label class="required" for="id_sender">Sender:</label>      ...
     <tr><th><label for="id_cc_myself">Cc myself:<label> ...
+    >>> f['subject'].label_tag()
+    <label class="required" for="id_subject">Subject:</label>
+    >>> f['subject'].label_tag(attrs={'class': 'foo'})
+    <label for="id_subject" class="foo required">Subject:</label>
+
+.. versionchanged:: 1.8
+
+    The ``required_css_class`` will also be added to the ``<label>`` tag as
+    seen above.
 
 .. _ref-forms-api-configuring-label:
 
@@ -799,6 +808,10 @@ additional attributes for the ``<label>`` tag.
     template, you could write a custom filter to allow passing parameters to
     ``label_tag``.
 
+.. versionchanged:: 1.8
+
+    The label includes :attr:`~Form.required_css_class` if applicable.
+
 .. method:: BoundField.css_classes()
 
 When you use Django's rendering shortcuts, CSS classes are used to

docs/releases/1.8.txt

@@ -112,6 +112,10 @@ Forms
 * The new :meth:`~django.forms.Form.has_error()` method allows checking
   if a specific error has happened.
 
+* If :attr:`~django.forms.Form.required_css_class` is defined on a form, then
+  the ``<label>`` tags for required fields will have this class present in its
+  attributes.
+
 Internationalization
 ^^^^^^^^^^^^^^^^^^^^
 

tests/forms_tests/tests/test_forms.py

@@ -1814,34 +1814,49 @@ class FormsTestCase(TestCase):
         p.error_css_class = 'error'
         p.required_css_class = 'required'
 
-        self.assertHTMLEqual(p.as_ul(), """<li class="required error"><ul class="errorlist"><li>This field is required.</li></ul><label for="id_name">Name:</label> <input type="text" name="name" id="id_name" /></li>
-<li class="required"><label for="id_is_cool">Is cool:</label> <select name="is_cool" id="id_is_cool">
+        self.assertHTMLEqual(p.as_ul(), """<li class="required error"><ul class="errorlist"><li>This field is required.</li></ul><label class="required" for="id_name">Name:</label> <input type="text" name="name" id="id_name" /></li>
+<li class="required"><label class="required" for="id_is_cool">Is cool:</label> <select name="is_cool" id="id_is_cool">
 <option value="1" selected="selected">Unknown</option>
 <option value="2">Yes</option>
 <option value="3">No</option>
 </select></li>
 <li><label for="id_email">Email:</label> <input type="email" name="email" id="id_email" /></li>
-<li class="required error"><ul class="errorlist"><li>This field is required.</li></ul><label for="id_age">Age:</label> <input type="number" name="age" id="id_age" /></li>""")
+<li class="required error"><ul class="errorlist"><li>This field is required.</li></ul><label class="required" for="id_age">Age:</label> <input type="number" name="age" id="id_age" /></li>""")
 
         self.assertHTMLEqual(p.as_p(), """<ul class="errorlist"><li>This field is required.</li></ul>
-<p class="required error"><label for="id_name">Name:</label> <input type="text" name="name" id="id_name" /></p>
-<p class="required"><label for="id_is_cool">Is cool:</label> <select name="is_cool" id="id_is_cool">
+<p class="required error"><label class="required" for="id_name">Name:</label> <input type="text" name="name" id="id_name" /></p>
+<p class="required"><label class="required" for="id_is_cool">Is cool:</label> <select name="is_cool" id="id_is_cool">
 <option value="1" selected="selected">Unknown</option>
 <option value="2">Yes</option>
 <option value="3">No</option>
 </select></p>
 <p><label for="id_email">Email:</label> <input type="email" name="email" id="id_email" /></p>
 <ul class="errorlist"><li>This field is required.</li></ul>
-<p class="required error"><label for="id_age">Age:</label> <input type="number" name="age" id="id_age" /></p>""")
+<p class="required error"><label class="required" for="id_age">Age:</label> <input type="number" name="age" id="id_age" /></p>""")
 
-        self.assertHTMLEqual(p.as_table(), """<tr class="required error"><th><label for="id_name">Name:</label></th><td><ul class="errorlist"><li>This field is required.</li></ul><input type="text" name="name" id="id_name" /></td></tr>
-<tr class="required"><th><label for="id_is_cool">Is cool:</label></th><td><select name="is_cool" id="id_is_cool">
+        self.assertHTMLEqual(p.as_table(), """<tr class="required error"><th><label class="required" for="id_name">Name:</label></th><td><ul class="errorlist"><li>This field is required.</li></ul><input type="text" name="name" id="id_name" /></td></tr>
+<tr class="required"><th><label class="required" for="id_is_cool">Is cool:</label></th><td><select name="is_cool" id="id_is_cool">
 <option value="1" selected="selected">Unknown</option>
 <option value="2">Yes</option>
 <option value="3">No</option>
 </select></td></tr>
 <tr><th><label for="id_email">Email:</label></th><td><input type="email" name="email" id="id_email" /></td></tr>
-<tr class="required error"><th><label for="id_age">Age:</label></th><td><ul class="errorlist"><li>This field is required.</li></ul><input type="number" name="age" id="id_age" /></td></tr>""")
+<tr class="required error"><th><label class="required" for="id_age">Age:</label></th><td><ul class="errorlist"><li>This field is required.</li></ul><input type="number" name="age" id="id_age" /></td></tr>""")
+
+    def test_label_has_required_css_class(self):
+        """
+        #17922 - required_css_class is added to the label_tag() of required fields.
+        """
+        class SomeForm(Form):
+            required_css_class = 'required'
+            field = CharField(max_length=10)
+            field2 = IntegerField(required=False)
+
+        f = SomeForm({'field': 'test'})
+        self.assertHTMLEqual(f['field'].label_tag(), '<label for="id_field" class="required">Field:</label>')
+        self.assertHTMLEqual(f['field'].label_tag(attrs={'class': 'foo'}),
+            '<label for="id_field" class="foo required">Field:</label>')
+        self.assertHTMLEqual(f['field2'].label_tag(), '<label for="id_field2">Field2:</label>')
 
     def test_label_split_datetime_not_displayed(self):
         class EventForm(Form):