Fixed #27037 -- Prevented required attribute on ClearableFileInput when initial data exists.

tests/forms_tests/tests/test_forms.py

@@ -2360,6 +2360,15 @@ Password: <input type="password" name="password" required />
             '<tr><th>File1:</th><td><input type="file" name="file1" required /></td></tr>',
         )
 
+        # A required file field with initial data should not contain the
+        # required HTML attribute. The file input is left blank by the user to
+        # keep the existing, initial value.
+        f = FileForm(initial={'file1': 'resume.txt'}, auto_id=False)
+        self.assertHTMLEqual(
+            f.as_table(),
+            '<tr><th>File1:</th><td><input type="file" name="file1" /></td></tr>',
+        )
+
     def test_basic_processing_in_view(self):
         class UserRegistration(Form):
             username = CharField(max_length=10)

tests/forms_tests/widget_tests/test_checkboxselectmultiple.py

@@ -112,3 +112,11 @@ class CheckboxSelectMultipleTest(WidgetTest):
         </ul>
         """
         self.check_html(widget, 'letters', ['a', 'c'], html=html)
+
+    def test_use_required_attribute(self):
+        widget = self.widget(choices=self.beatles)
+        # Always False because browser validation would require all checkboxes
+        # to be checked instead of at least one.
+        self.assertIs(widget.use_required_attribute(None), False)
+        self.assertIs(widget.use_required_attribute([]), False)
+        self.assertIs(widget.use_required_attribute(['J', 'P']), False)

tests/forms_tests/widget_tests/test_clearablefileinput.py

@@ -143,3 +143,9 @@ class ClearableFileInputTest(WidgetTest):
 
         html = self.widget.render('myfile', NoURLFieldFile())
         self.assertHTMLEqual(html, '<input name="myfile" type="file" />')
+
+    def test_use_required_attribute(self):
+        # False when initial data exists. The file input is left blank by the
+        # user to keep the existing, initial value.
+        self.assertIs(self.widget.use_required_attribute(None), True)
+        self.assertIs(self.widget.use_required_attribute('resume.txt'), False)

tests/forms_tests/widget_tests/test_hiddeninput.py

@@ -8,3 +8,10 @@ class HiddenInputTest(WidgetTest):
 
     def test_render(self):
         self.check_html(self.widget, 'email', '', html='<input type="hidden" name="email" />')
+
+    def test_use_required_attribute(self):
+        # Always False to avoid browser validation on inputs hidden from the
+        # user.
+        self.assertIs(self.widget.use_required_attribute(None), False)
+        self.assertIs(self.widget.use_required_attribute(''), False)
+        self.assertIs(self.widget.use_required_attribute('foo'), False)

tests/forms_tests/widget_tests/test_textinput.py

@@ -76,3 +76,9 @@ class TextInputTest(WidgetTest):
     def test_attrs_safestring(self):
         widget = TextInput(attrs={'onBlur': mark_safe("function('foo')")})
         self.check_html(widget, 'email', '', html='<input onBlur="function(\'foo\')" type="text" name="email" />')
+
+    def test_use_required_attribute(self):
+        # Text inputs can safely trigger the browser validation.
+        self.assertIs(self.widget.use_required_attribute(None), True)
+        self.assertIs(self.widget.use_required_attribute(''), True)
+        self.assertIs(self.widget.use_required_attribute('resume.txt'), True)