Add GovukSearchField - extends SearchField

app/main/forms.py

@@ -294,6 +294,23 @@ class GovukEmailField(EmailField):
         return govuk_field_widget(self, field, type="email", param_extensions=params, **kwargs)
 
 
+class GovukSearchField(SearchField):
+    def __init__(self, label='', validators=None, param_extensions=None, **kwargs):
+        super(GovukSearchField, self).__init__(label, validators, **kwargs)
+        self.param_extensions = param_extensions
+
+    # self.__call__ renders the HTML for the field by:
+    # 1. delegating to self.meta.render_field which
+    # 2. calls field.widget
+    # this bypasses that by making self.widget a method with the same interface as widget.__call__
+    def widget(self, field, param_extensions=None, **kwargs):
+
+        params = {"classes": "govuk-!-width-full"}  # email addresses don't need to be spellchecked
+        if param_extensions:
+            params.update(param_extensions)
+        return govuk_field_widget(self, field, type="search", param_extensions=params, **kwargs)
+
+
 class SMSCode(StringField):
     validators = [
         DataRequired(message='Cannot be empty'),