Fixed #4752 -- Make default ErrorList customisable in newforms display. Based on a patch from michal@logix.cz and SmileyChris.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@6142 bcc190cf-cafb-0310-a4f2-bffc1f526a37

3 files changed, 54 insertions, 4 deletions

diff --git a/django/newforms/forms.py b/django/newforms/forms.py
index 906978c86f..5baf0a079b 100644
--- a/django/newforms/forms.py
+++ b/django/newforms/forms.py
@@ -57,13 +57,15 @@ class BaseForm(StrAndUnicode):
     # class is different than Form. See the comments by the Form class for more
     # information. Any improvements to the form API should be made to *this*
     # class, not to the Form class.
-    def __init__(self, data=None, files=None, auto_id='id_%s', prefix=None, initial=None):
+    def __init__(self, data=None, files=None, auto_id='id_%s', prefix=None,
+            initial=None, error_class=ErrorList):
         self.is_bound = data is not None or files is not None
         self.data = data or {}
         self.files = files or {}
         self.auto_id = auto_id
         self.prefix = prefix
         self.initial = initial or {}
+        self.error_class = error_class
         self._errors = None # Stores the errors after clean() has been called.
 
         # The base_fields class attribute is the *class-wide* definition of
@@ -117,7 +119,7 @@ class BaseForm(StrAndUnicode):
         output, hidden_fields = [], []
         for name, field in self.fields.items():
             bf = BoundField(self, field, name)
-            bf_errors = ErrorList([escape(error) for error in bf.errors]) # Escape and cache in local variable.
+            bf_errors = self.error_class([escape(error) for error in bf.errors]) # Escape and cache in local variable.
             if bf.is_hidden:
                 if bf_errors:
                     top_errors.extend(['(Hidden field %s) %s' % (name, force_unicode(e)) for e in bf_errors])
@@ -168,7 +170,7 @@ class BaseForm(StrAndUnicode):
         field -- i.e., from Form.clean(). Returns an empty ErrorList if there
         are none.
         """
-        return self.errors.get(NON_FIELD_ERRORS, ErrorList())
+        return self.errors.get(NON_FIELD_ERRORS, self.error_class())
 
     def full_clean(self):
         """
@@ -241,7 +243,7 @@ class BoundField(StrAndUnicode):
         Returns an ErrorList for this field. Returns an empty ErrorList
         if there are none.
         """
-        return self.form.errors.get(self.name, ErrorList())
+        return self.form.errors.get(self.name, self.form.error_class())
     errors = property(_errors)
 
     def as_widget(self, widget=None, attrs=None):
diff --git a/docs/newforms.txt b/docs/newforms.txt
index 32c4441eb2..33625f39b8 100644
--- a/docs/newforms.txt
+++ b/docs/newforms.txt
@@ -554,6 +554,29 @@ method you're using::
     <p>Sender: <input type="text" name="sender" value="invalid e-mail address" /></p>
     <p>Cc myself: <input checked="checked" type="checkbox" name="cc_myself" /></p>
 
+Customizing the error list format
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+By default, forms use ``django.newforms.util.ErrorList`` to format validation
+errors. If you'd like to use an alternate class for displaying errors, you can
+pass that in at construction time::
+
+    >>> from django.newforms.util import ErrorList
+    >>> class DivErrorList(ErrorList):
+    ...     def __unicode__(self):
+    ...         return self.as_divs()
+    ...     def as_divs(self):
+    ...         if not self: return u''
+    ...         return u'<div class="errorlist">%s</div>' % ''.join([u'<div class="error">%s</div>' % e for e in self])
+    >>> f = ContactForm(data, auto_id=False, error_class=DivErrorList)
+    >>> f.as_p()
+    <div class="errorlist"><div class="error">This field is required.</div></div>
+    <p>Subject: <input type="text" name="subject" maxlength="100" /></p>
+    <p>Message: <input type="text" name="message" value="Hi there" /></p>
+    <div class="errorlist"><div class="error">Enter a valid e-mail address.</div></div>
+    <p>Sender: <input type="text" name="sender" value="invalid e-mail address" /></p>
+    <p>Cc myself: <input checked="checked" type="checkbox" name="cc_myself" /></p>
+
 More granular output
 ~~~~~~~~~~~~~~~~~~~~
 
diff --git a/tests/regressiontests/forms/tests.py b/tests/regressiontests/forms/tests.py
index 0df3ee3858..2477eb1cef 100644
--- a/tests/regressiontests/forms/tests.py
+++ b/tests/regressiontests/forms/tests.py
@@ -3821,6 +3821,31 @@ u''
 True
 >>> f.cleaned_data['username']
 u'sirrobin'
+
+#######################################
+# Test overriding ErrorList in a form #
+#######################################
+
+>>> from django.newforms.util import ErrorList
+>>> class DivErrorList(ErrorList):
+...     def __unicode__(self):
+...         return self.as_divs()
+...     def as_divs(self):
+...         if not self: return u''
+...         return u'<div class="errorlist">%s</div>' % ''.join([u'<div class="error">%s</div>' % e for e in self])
+>>> class CommentForm(Form):
+...     name = CharField(max_length=50, required=False)
+...     email = EmailField()
+...     comment = CharField()
+>>> data = dict(email='invalid')
+>>> f = CommentForm(data, auto_id=False, error_class=DivErrorList)
+>>> print f.as_p()
+<p>Name: <input type="text" name="name" maxlength="50" /></p>
+<div class="errorlist"><div class="error">Enter a valid e-mail address.</div></div>
+<p>Email: <input type="text" name="email" value="invalid" /></p>
+<div class="errorlist"><div class="error">This field is required.</div></div>
+<p>Comment: <input type="text" name="comment" /></p>
+
 """
 
 __test__ = {