rewrite tutorial docs and example

examples/tutorial/tests/test_auth.py

@@ -0,0 +1,66 @@
+import pytest
+from flask import g, session
+from flaskr.db import get_db
+
+
+def test_register(client, app):
+    # test that viewing the page renders without template errors
+    assert client.get('/auth/register').status_code == 200
+
+    # test that successful registration redirects to the login page
+    response = client.post(
+        '/auth/register', data={'username': 'a', 'password': 'a'}
+    )
+    assert 'http://localhost/auth/login' == response.headers['Location']
+
+    # test that the user was inserted into the database
+    with app.app_context():
+        assert get_db().execute(
+            "select * from user where username = 'a'",
+        ).fetchone() is not None
+
+
+@pytest.mark.parametrize(('username', 'password', 'message'), (
+    ('', '', b'Username is required.'),
+    ('a', '', b'Password is required.'),
+    ('test', 'test', b'already registered'),
+))
+def test_register_validate_input(client, username, password, message):
+    response = client.post(
+        '/auth/register',
+        data={'username': username, 'password': password}
+    )
+    assert message in response.data
+
+
+def test_login(client, auth):
+    # test that viewing the page renders without template errors
+    assert client.get('/auth/login').status_code == 200
+
+    # test that successful login redirects to the index page
+    response = auth.login()
+    assert response.headers['Location'] == 'http://localhost/'
+
+    # login request set the user_id in the session
+    # check that the user is loaded from the session
+    with client:
+        client.get('/')
+        assert session['user_id'] == 1
+        assert g.user['username'] == 'test'
+
+
+@pytest.mark.parametrize(('username', 'password', 'message'), (
+    ('a', 'test', b'Incorrect username.'),
+    ('test', 'a', b'Incorrect password.'),
+))
+def test_login_validate_input(auth, username, password, message):
+    response = auth.login(username, password)
+    assert message in response.data
+
+
+def test_logout(client, auth):
+    auth.login()
+
+    with client:
+        auth.logout()
+        assert 'user_id' not in session