Fixed #17549 -- Added a clickable link for URLFields in admin change list.

django/contrib/admin/static/admin/css/widgets.css

@@ -225,6 +225,21 @@ table p.datetime {
     padding-left: 0;
 }
 
+/* URL */
+
+p.url {
+    line-height: 20px;
+    margin: 0;
+    padding: 0;
+    color: #666;
+    font-size: 11px;
+    font-weight: bold;
+}
+
+.url a {
+    font-weight: normal;
+}
+
 /* FILE UPLOADS */
 
 p.file-upload {

django/contrib/admin/widgets.py

@@ -10,7 +10,7 @@ from django.contrib.admin.templatetags.admin_static import static
 from django.core.urlresolvers import reverse
 from django.forms.widgets import RadioFieldRenderer
 from django.forms.util import flatatt
-from django.utils.html import escape, format_html, format_html_join
+from django.utils.html import escape, format_html, format_html_join, smart_urlquote
 from django.utils.text import Truncator
 from django.utils.translation import ugettext as _
 from django.utils.safestring import mark_safe
@@ -306,6 +306,19 @@ class AdminURLFieldWidget(forms.TextInput):
             final_attrs.update(attrs)
         super(AdminURLFieldWidget, self).__init__(attrs=final_attrs)
 
+    def render(self, name, value, attrs=None):
+        html = super(AdminURLFieldWidget, self).render(name, value, attrs)
+        if value:
+            value = force_text(self._format_value(value))
+            final_attrs = {'href': mark_safe(smart_urlquote(value))}
+            html = format_html(
+                '<p class="url">{0} <a {1}>{2}</a><br />{3} {4}</p>',
+                _('Currently:'), flatatt(final_attrs), value,
+                _('Change:'), html
+            )
+        return html
+
+
 class AdminIntegerFieldWidget(forms.TextInput):
     class_name = 'vIntegerField'
 

docs/ref/models/fields.txt

@@ -922,6 +922,11 @@ Like all :class:`CharField` subclasses, :class:`URLField` takes the optional
 :attr:`~CharField.max_length`argument. If you don't specify
 :attr:`~CharField.max_length`, a default of 200 is used.
 
+.. versionadded:: 1.5
+
+The current value of the field will be displayed as a clickable link above the
+input widget.
+
 
 Relationship fields
 ===================

tests/regressiontests/admin_widgets/tests.py

@@ -266,6 +266,37 @@ class AdminSplitDateTimeWidgetTest(DjangoTestCase):
                 )
 
 
+class AdminURLWidgetTest(DjangoTestCase):
+    def test_render(self):
+        w = widgets.AdminURLFieldWidget()
+        self.assertHTMLEqual(
+            conditional_escape(w.render('test', '')),
+            '<input class="vURLField" name="test" type="text" />'
+        )
+        self.assertHTMLEqual(
+            conditional_escape(w.render('test', 'http://example.com')),
+            '<p class="url">Currently:<a href="http://example.com">http://example.com</a><br />Change:<input class="vURLField" name="test" type="text" value="http://example.com" /></p>'
+        )
+
+    def test_render_idn(self):
+        w = widgets.AdminURLFieldWidget()
+        self.assertHTMLEqual(
+            conditional_escape(w.render('test', 'http://example-äüö.com')),
+            '<p class="url">Currently:<a href="http://xn--example--7za4pnc.com">http://example-äüö.com</a><br />Change:<input class="vURLField" name="test" type="text" value="http://example-äüö.com" /></p>'
+        )
+
+    def test_render_quoting(self):
+        w = widgets.AdminURLFieldWidget()
+        self.assertHTMLEqual(
+            conditional_escape(w.render('test', 'http://example.com/<sometag>some text</sometag>')),
+            '<p class="url">Currently:<a href="http://example.com/%3Csometag%3Esome%20text%3C/sometag%3E">http://example.com/&lt;sometag&gt;some text&lt;/sometag&gt;</a><br />Change:<input class="vURLField" name="test" type="text" value="http://example.com/<sometag>some text</sometag>" /></p>'
+        )
+        self.assertHTMLEqual(
+            conditional_escape(w.render('test', 'http://example-äüö.com/<sometag>some text</sometag>')),
+            '<p class="url">Currently:<a href="http://xn--example--7za4pnc.com/%3Csometag%3Esome%20text%3C/sometag%3E">http://example-äüö.com/&lt;sometag&gt;some text&lt;/sometag&gt;</a><br />Change:<input class="vURLField" name="test" type="text" value="http://example-äüö.com/<sometag>some text</sometag>" /></p>'
+        )
+
+
 class AdminFileWidgetTest(DjangoTestCase):
     def test_render(self):
         band = models.Band.objects.create(name='Linkin Park')