newforms: Implemented RadioSelect, with unit tests

git-svn-id: http://code.djangoproject.com/svn/django/trunk@4072 bcc190cf-cafb-0310-a4f2-bffc1f526a37

2 files changed, 155 insertions, 4 deletions

diff --git a/django/newforms/widgets.py b/django/newforms/widgets.py
index b24f91f4c6..c9b3d02913 100644
--- a/django/newforms/widgets.py
+++ b/django/newforms/widgets.py
@@ -5,7 +5,7 @@ HTML Widget classes
 __all__ = (
     'Widget', 'TextInput', 'PasswordInput', 'HiddenInput', 'FileInput',
     'Textarea', 'CheckboxInput',
-    'Select', 'SelectMultiple',
+    'Select', 'SelectMultiple', 'RadioSelect',
 )
 
 from django.utils.html import escape
@@ -35,7 +35,10 @@ class Widget(object):
         return attrs
 
 class Input(Widget):
-    "Base class for all <input> widgets (except type='checkbox', which is special)"
+    """
+    Base class for all <input> widgets (except type='checkbox' and
+    type='radio', which are special).
+    """
     input_type = None # Subclasses must define this.
     def render(self, name, value, attrs=None):
         if value is None: value = ''
@@ -102,8 +105,45 @@ class SelectMultiple(Widget):
         output.append(u'</select>')
         return u'\n'.join(output)
 
-class RadioSelect(Widget):
-    pass
+class RadioInput(object):
+    "An object used by RadioFieldRenderer that represents a single <input type='radio'>."
+    def __init__(self, name, value, attrs, choice):
+        self.name, self.value = name, value
+        self.attrs = attrs or {}
+        self.choice_value, self.choice_label = choice
+
+    def __str__(self):
+        return u'<label>%s %s</label>' % (self.tag(), self.choice_label)
+
+    def is_checked(self):
+        return self.value == str(self.choice_value)
+
+    def tag(self):
+        final_attrs = dict(self.attrs, type='radio', name=self.name, value=self.choice_value)
+        if self.is_checked():
+            final_attrs['checked'] = 'checked'
+        return u'<input%s />' % flatatt(final_attrs)
+
+class RadioFieldRenderer(object):
+    "An object used by RadioSelect to enable customization of radio widgets."
+    def __init__(self, name, value, attrs, choices):
+        self.name, self.value, self.attrs = name, value, attrs
+        self.choices = choices
+
+    def __iter__(self):
+        for choice in self.choices:
+            yield RadioInput(self.name, self.value, self.attrs, choice)
+
+    def __str__(self):
+        "Outputs a <ul> for this set of radio fields."
+        return u'<ul>\n%s\n</ul>' % u'\n'.join([u'<li>%s</li>' % w for w in self])
+
+class RadioSelect(Select):
+    def render(self, name, value, attrs=None, choices=()):
+        "Returns a RadioFieldRenderer instance rather than a Unicode string."
+        if value is None: value = ''
+        str_value = str(value) # Normalize to string.
+        return RadioFieldRenderer(name, str_value, attrs, list(chain(self.choices, choices)))
 
 class CheckboxSelectMultiple(Widget):
     pass
diff --git a/tests/regressiontests/forms/tests.py b/tests/regressiontests/forms/tests.py
index 5402f654e9..42596b02e0 100644
--- a/tests/regressiontests/forms/tests.py
+++ b/tests/regressiontests/forms/tests.py
@@ -340,6 +340,117 @@ If 'choices' is passed to both the constructor and render(), then they'll both b
 <option value="5">5</option>
 </select>
 
+# RadioSelect Widget ##########################################################
+
+>>> w = RadioSelect()
+>>> print w.render('beatle', 'J', choices=(('J', 'John'), ('P', 'Paul'), ('G', 'George'), ('R', 'Ringo')))
+<ul>
+<li><label><input checked="checked" type="radio" name="beatle" value="J" /> John</label></li>
+<li><label><input type="radio" name="beatle" value="P" /> Paul</label></li>
+<li><label><input type="radio" name="beatle" value="G" /> George</label></li>
+<li><label><input type="radio" name="beatle" value="R" /> Ringo</label></li>
+</ul>
+
+If the value is None, none of the options are checked:
+>>> print w.render('beatle', None, choices=(('J', 'John'), ('P', 'Paul'), ('G', 'George'), ('R', 'Ringo')))
+<ul>
+<li><label><input type="radio" name="beatle" value="J" /> John</label></li>
+<li><label><input type="radio" name="beatle" value="P" /> Paul</label></li>
+<li><label><input type="radio" name="beatle" value="G" /> George</label></li>
+<li><label><input type="radio" name="beatle" value="R" /> Ringo</label></li>
+</ul>
+
+If the value corresponds to a label (but not to an option value), none of the options are checked:
+>>> print w.render('beatle', 'John', choices=(('J', 'John'), ('P', 'Paul'), ('G', 'George'), ('R', 'Ringo')))
+<ul>
+<li><label><input type="radio" name="beatle" value="J" /> John</label></li>
+<li><label><input type="radio" name="beatle" value="P" /> Paul</label></li>
+<li><label><input type="radio" name="beatle" value="G" /> George</label></li>
+<li><label><input type="radio" name="beatle" value="R" /> Ringo</label></li>
+</ul>
+
+The value is compared to its str():
+>>> print w.render('num', 2, choices=[('1', '1'), ('2', '2'), ('3', '3')])
+<ul>
+<li><label><input type="radio" name="num" value="1" /> 1</label></li>
+<li><label><input checked="checked" type="radio" name="num" value="2" /> 2</label></li>
+<li><label><input type="radio" name="num" value="3" /> 3</label></li>
+</ul>
+>>> print w.render('num', '2', choices=[(1, 1), (2, 2), (3, 3)])
+<ul>
+<li><label><input type="radio" name="num" value="1" /> 1</label></li>
+<li><label><input checked="checked" type="radio" name="num" value="2" /> 2</label></li>
+<li><label><input type="radio" name="num" value="3" /> 3</label></li>
+</ul>
+>>> print w.render('num', 2, choices=[(1, 1), (2, 2), (3, 3)])
+<ul>
+<li><label><input type="radio" name="num" value="1" /> 1</label></li>
+<li><label><input checked="checked" type="radio" name="num" value="2" /> 2</label></li>
+<li><label><input type="radio" name="num" value="3" /> 3</label></li>
+</ul>
+
+The 'choices' argument can be any iterable:
+>>> def get_choices():
+...     for i in range(5):
+...         yield (i, i)
+>>> print w.render('num', 2, choices=get_choices())
+<ul>
+<li><label><input type="radio" name="num" value="0" /> 0</label></li>
+<li><label><input type="radio" name="num" value="1" /> 1</label></li>
+<li><label><input checked="checked" type="radio" name="num" value="2" /> 2</label></li>
+<li><label><input type="radio" name="num" value="3" /> 3</label></li>
+<li><label><input type="radio" name="num" value="4" /> 4</label></li>
+</ul>
+
+You can also pass 'choices' to the constructor:
+>>> w = RadioSelect(choices=[(1, 1), (2, 2), (3, 3)])
+>>> print w.render('num', 2)
+<ul>
+<li><label><input type="radio" name="num" value="1" /> 1</label></li>
+<li><label><input checked="checked" type="radio" name="num" value="2" /> 2</label></li>
+<li><label><input type="radio" name="num" value="3" /> 3</label></li>
+</ul>
+
+If 'choices' is passed to both the constructor and render(), then they'll both be in the output:
+>>> print w.render('num', 2, choices=[(4, 4), (5, 5)])
+<ul>
+<li><label><input type="radio" name="num" value="1" /> 1</label></li>
+<li><label><input checked="checked" type="radio" name="num" value="2" /> 2</label></li>
+<li><label><input type="radio" name="num" value="3" /> 3</label></li>
+<li><label><input type="radio" name="num" value="4" /> 4</label></li>
+<li><label><input type="radio" name="num" value="5" /> 5</label></li>
+</ul>
+
+The render() method returns a RadioFieldRenderer object, whose str() is a <ul>.
+You can manipulate that object directly to customize the way the RadioSelect
+is rendered.
+>>> w = RadioSelect()
+>>> r = w.render('beatle', 'J', choices=(('J', 'John'), ('P', 'Paul'), ('G', 'George'), ('R', 'Ringo')))
+>>> for inp in r:
+...     print inp
+<label><input checked="checked" type="radio" name="beatle" value="J" /> John</label>
+<label><input type="radio" name="beatle" value="P" /> Paul</label>
+<label><input type="radio" name="beatle" value="G" /> George</label>
+<label><input type="radio" name="beatle" value="R" /> Ringo</label>
+>>> for inp in r:
+...     print '%s<br />' % inp
+<label><input checked="checked" type="radio" name="beatle" value="J" /> John</label><br />
+<label><input type="radio" name="beatle" value="P" /> Paul</label><br />
+<label><input type="radio" name="beatle" value="G" /> George</label><br />
+<label><input type="radio" name="beatle" value="R" /> Ringo</label><br />
+>>> for inp in r:
+...     print '<p>%s %s</p>' % (inp.tag(), inp.choice_label)
+<p><input checked="checked" type="radio" name="beatle" value="J" /> John</p>
+<p><input type="radio" name="beatle" value="P" /> Paul</p>
+<p><input type="radio" name="beatle" value="G" /> George</p>
+<p><input type="radio" name="beatle" value="R" /> Ringo</p>
+>>> for inp in r:
+...     print '%s %s %s %s %s' % (inp.name, inp.value, inp.choice_value, inp.choice_label, inp.is_checked())
+beatle J J John True
+beatle J P Paul False
+beatle J G George False
+beatle J R Ringo False
+
 # CharField ###################################################################
 
 >>> f = CharField(required=False)