add javascript ajax example

examples/javascript/tests/conftest.py

@@ -0,0 +1,15 @@
+import pytest
+
+from js_example import app
+
+
+@pytest.fixture(name='app')
+def fixture_app():
+    app.testing = True
+    yield app
+    app.testing = False
+
+
+@pytest.fixture
+def client(app):
+    return app.test_client()

examples/javascript/tests/test_js_example.py

@@ -0,0 +1,28 @@
+import pytest
+
+from flask import template_rendered
+
+
+@pytest.mark.parametrize(('path', 'template_name'), (
+    ('/', 'plain.html'),
+    ('/plain', 'plain.html'),
+    ('/fetch', 'fetch.html'),
+    ('/jquery', 'jquery.html'),
+))
+def test_index(app, client, path, template_name):
+    def check(sender, template, context):
+        assert template.name == template_name
+
+    with template_rendered.connected_to(check, app):
+        client.get(path)
+
+
+@pytest.mark.parametrize(('a', 'b', 'result'), (
+    (2, 3, 5),
+    (2.5, 3, 5.5),
+    (2, None, 2),
+    (2, 'b', 2),
+))
+def test_add(client, a, b, result):
+    response = client.post('/add', data={'a': a, 'b': b})
+    assert response.get_json()['result'] == result