Fixes UnicodeEncodeError in `wagtailforms`

If you will create form field entry with unicode characters,
you will get `UnicodeEncodeError`. This commit fixes this bug.

CHANGELOG.txt

@@ -47,6 +47,7 @@ Changelog
  * Fix: StreamField block controls are no longer hidden by the StreamField menu when prepending a new block (Vincent Audebert)
  * Fix: Removed invalid use of `__` alias that prevented strings getting picked up for translation (Juha Yrjölä)
  * Fix: Routable pages without a main view no longer raise a `TypeError` (Bojan Mihelac)
+ * Fix: Fixed UnicodeEncodeError in wagtailforms when downloading a CSV for a form containing non-ASCII field labels on Python 2 (Mikalai Radchuk)
 
 
 1.4.4 (xx.xx.2016)

docs/releases/1.5.rst

@@ -85,6 +85,7 @@ Bug fixes
  * StreamField block controls are no longer hidden by the StreamField menu when prepending a new block (Vincent Audebert)
  * Removed invalid use of ``__`` alias that prevented strings getting picked up for translation (Juha Yrjölä)
  * :ref:`Routable pages <routable_page_mixin>` without a main view no longer raise a ``TypeError`` (Bojan Mihelac)
+ * Fixed UnicodeEncodeError in wagtailforms when downloading a CSV for a form containing non-ASCII field labels on Python 2 (Mikalai Radchuk)
 
 
 Upgrade considerations

wagtail/wagtailforms/tests.py

@@ -552,7 +552,7 @@ class TestFormsSubmissions(TestCase, WagtailTestUtils):
         self.assertEqual(data_lines[0], 'Submission date,Your email,Your message,Your choices\r')
         self.assertEqual(data_lines[1], '2014-01-01 12:00:00+00:00,new@example.com,this is a fairly new message,None\r')
 
-    def test_list_submissions_csv_export_with_unicode(self):
+    def test_list_submissions_csv_export_with_unicode_in_submission(self):
         unicode_form_submission = FormSubmission.objects.create(
             page=self.form_page,
             form_data=json.dumps({
@@ -573,6 +573,39 @@ class TestFormsSubmissions(TestCase, WagtailTestUtils):
         data_line = response.content.decode('utf-8').split("\n")[1]
         self.assertIn('こんにちは、世界', data_line)
 
+    def test_list_submissions_csv_export_with_unicode_in_field(self):
+        FormField.objects.create(
+            page=self.form_page,
+            sort_order=2,
+            label="Выберите самую любимую IDE для разработке на Python",
+            help_text="Вы можете выбрать только один вариант",
+            field_type='radio',
+            required=True,
+            choices='PyCharm,vim,nano',
+        )
+        unicode_form_submission = FormSubmission.objects.create(
+            page=self.form_page,
+            form_data=json.dumps({
+                'your-email': "unicode@example.com",
+                'your-message': "We don\'t need unicode here",
+                'vyberite-samuiu-liubimuiu-ide-dlia-razrabotke-na-python': "vim",
+            }),
+        )
+        unicode_form_submission.submit_time = '2014-01-02T12:00:00.000Z'
+        unicode_form_submission.save()
+
+        response = self.client.get(
+            reverse('wagtailforms:list_submissions', args=(self.form_page.id, )),
+            {'date_from': '01/02/2014', 'action': 'CSV'}
+        )
+
+        # Check response
+        self.assertEqual(response.status_code, 200)
+
+        data_lines = response.content.decode('utf-8').split("\n")
+        self.assertIn('Выберите самую любимую IDE для разработке на Python', data_lines[0])
+        self.assertIn('vim', data_lines[1])
+
 
 class TestDeleteFormSubmission(TestCase):
     fixtures = ['test.json']

wagtail/wagtailforms/views.py

@@ -80,7 +80,7 @@ def list_submissions(request, page_id):
 
         writer = csv.writer(response)
 
-        header_row = ['Submission date'] + [label for name, label in data_fields]
+        header_row = ['Submission date'] + [smart_str(label) for name, label in data_fields]
 
         writer.writerow(header_row)
         for s in submissions: