fix TypeError if submitting unchecked BooleanField

wagtail/wagtailforms/models.py

@@ -196,7 +196,7 @@ class AbstractEmailForm(AbstractForm):
         super(AbstractEmailForm, self).process_form_submission(form)
 
         if self.to_address:
-            content = '\n'.join([x[1].label + ': ' + form.data.get(x[0]) for x in form.fields.items()])
+            content = '\n'.join([x[1].label + ': ' + str(form.data.get(x[0])) for x in form.fields.items()])
             send_mail(self.subject, content, [self.to_address], self.from_address,)
 
 

wagtail/wagtailforms/tests.py

@@ -1,5 +1,4 @@
 import json
-import unittest
 
 from django.test import TestCase
 from django.core import mail
@@ -79,7 +78,6 @@ class TestFormSubmission(TestCase):
         self.assertIn("bar", submission[0].form_data)
         self.assertIn("baz", submission[0].form_data)
 
-    @unittest.expectedFailure
     def test_post_blank_checkbox(self):
         response = self.client.post('/contact-us/', {
             'your-email': 'bob@example.com',