[Test] Add test for disabled registration

It can temporarily change an app configuration value.

.gitignore

@@ -4,3 +4,5 @@ __pycache__/
 /calsocial/translations/*/LC_MESSAGES/*.mo
 /.pytest_cache/
 /.env
+/.coverage
+/htmlcov/

tests/helpers.py

@@ -17,6 +17,8 @@
 """Helper functions and fixtures for testing
 """
 
+from contextlib import contextmanager
+
 import pytest
 
 import calsocial
@@ -70,3 +72,22 @@ def database():
         yield db
 
         db.drop_all()
+
+
+@contextmanager
+def alter_config(app, **kwargs):
+    saved = {}
+
+    for key, value in kwargs.items():
+        if key in app.config:
+            saved[key] = app.config[key]
+
+        app.config[key] = value
+
+    yield
+
+    for key, value in kwargs.items():
+        if key in saved:
+            app.config[key] = saved[key]
+        else:
+            del app.config[key]

tests/test_register.py

@@ -20,7 +20,7 @@
 import calsocial
 from calsocial.models import db, User
 
-from helpers import client
+from helpers import alter_config, client
 
 
 def test_register_page(client):
@@ -113,3 +113,9 @@ def test_register_existing_email(client):
         'password_retype': 'password',
     })
     assert b'This email address can not be used' in page.data
+
+
+def test_registration_disabled(client):
+    with alter_config(calsocial.app, REGISTRATION_ENABLED=False):
+        page = client.get('/accounts/register')
+        assert b'Registration is disabled' in page.data