'FileInput widgets never render the value attribute. The old value
isn\'t useful if a form is updated or an error occurred.'

def test_render(self):

    self.check_html(self.widget, 'email', 'test@example.com', html='<input    type="file"    name="email"    />')
    self.check_html(self.widget, 'email', '', html='<input    type="file"    name="email"    />')
    self.check_html(self.widget, 'email', None, html='<input    type="file"    name="email"    />')
