Remove support for class_name attribute on icon tag

wagtail/admin/templatetags/wagtailadmin_tags.py

@@ -681,7 +681,7 @@ def versioned_static(path):
 
 
 @register.inclusion_tag("wagtailadmin/shared/icon.html", takes_context=False)
-def icon(name=None, classname=None, title=None, wrapped=False, class_name=None):
+def icon(name=None, classname=None, title=None, wrapped=False):
     """
     Abstracts away the actual icon implementation.
 
@@ -698,15 +698,6 @@ def icon(name=None, classname=None, title=None, wrapped=False, class_name=None):
     if not name:
         raise ValueError("You must supply an icon name")
 
-    if class_name:
-        warn(
-            (
-                "Icon template tag `class_name` has been renamed to `classname`, please adopt the new usage instead. "
-                f'Replace `{{% icon ... class_name="{class_name}" %}}` with `{{% icon ... classname="{class_name}" %}}`'
-            ),
-            category=RemovedInWagtail60Warning,
-        )
-
     deprecated_icons = [
         "angle-double-left",
         "angle-double-right",
@@ -750,8 +741,7 @@ def icon(name=None, classname=None, title=None, wrapped=False, class_name=None):
 
     return {
         "name": name,
-        # supporting class_name for backwards compatibility
-        "classname": classname or class_name or "icon",
+        "classname": classname or "icon",
         "title": title,
         "wrapped": wrapped,
     }

wagtail/admin/tests/test_templatetags.py

@@ -583,27 +583,6 @@ class IconTagTest(SimpleTestCase):
 
         self.assertHTMLEqual(expected, Template(template).render(Context()))
 
-    def test_with_classes_obsolete_keyword(self):
-        template = """
-            {% load wagtailadmin_tags %}
-            {% icon name="doc-empty" class_name="myclass" %}
-        """
-
-        expected = """
-            <svg aria-hidden="true" class="icon icon-doc-empty myclass"><use href="#icon-doc-empty"></svg>
-        """
-
-        with self.assertWarnsMessage(
-            RemovedInWagtail60Warning,
-            (
-                "Icon template tag `class_name` has been renamed to `classname`, "
-                "please adopt the new usage instead. Replace "
-                '`{% icon ... class_name="myclass" %}` with '
-                '`{% icon ... classname="myclass" %}`'
-            ),
-        ):
-            self.assertHTMLEqual(expected, Template(template).render(Context()))
-
     def test_with_deprecated_icon(self):
         template = """
             {% load wagtailadmin_tags %}