Merge pull request #605 from iommirocks/required-lambda-on-field-broken

iommi/form.py

@@ -924,6 +924,8 @@ def on_bind(self) -> None:
         # Not strict evaluate on purpose
         self.model = evaluate(self.model, **self.iommi_evaluate_parameters())
 
+        self.required = evaluate_strict(self.required, **self.iommi_evaluate_parameters())
+
         self.bind_from_instance()
 
         bind_member(self, name='label')
@@ -999,6 +1001,8 @@ def _validate(self):
             if self.parsed_data is not None:
                 value = self._validate_parsed_data(self.parsed_data)
 
+        assert not callable(self.required)
+
         if not self._errors:
             if (
                 form.mode is FULL_FORM_FROM_REQUEST

iommi/form__tests.py

@@ -3922,3 +3922,11 @@ class MyForm(Form):
         foo = Template('supernaut')
 
     assert 'supernaut' in MyForm().bind(request=req('get')).__html__()
+
+
+def test_required_truthy_bug():
+    form = Form.create(auto__model=Album, fields__genres__required=lambda **_: False).bind(request=req('post', **{'-submit': ''}))
+
+    assert form.actions.submit.iommi_name() == 'submit'
+    assert 'genres' not in form.get_errors()['fields']
+    assert form.get_errors()['fields']['name'] == {'This field is required'}