Improvement test_client can accept instance object. (#1083)

* Improvement test_client that can accept instance object.

* Increase code test coverage.

* Change parameter from lambda to object instance.

* Add new testcase about testing test_client can accept object instance as parameter

* Add negative test case -- passing to  test_client application with wrong event loop.

* Fix bug in test case

* Check where args and kwargs are empty or not.

aiohttp/pytest_plugin.py

@@ -2,6 +2,7 @@
 import contextlib
 
 import pytest
+from aiohttp.web import Application
 
 from .test_utils import (TestClient, loop_context, setup_test_loop,
                          teardown_test_loop)
@@ -55,7 +56,16 @@ def test_client(loop):
 
     @asyncio.coroutine
     def _create_from_app_factory(app_factory, *args, **kwargs):
-        app = app_factory(loop, *args, **kwargs)
+        if not isinstance(app_factory, Application):
+            app = app_factory(loop, *args, **kwargs)
+        else:
+            assert not args, "args should be empty"
+            assert not kwargs, "kwargs should be empty"
+            app = app_factory
+
+        assert app.loop is loop, \
+            "Application is attached to other event loop"
+
         client = TestClient(app)
         yield from client.start_server()
         clients.append(client)

docs/testing.rst

@@ -40,13 +40,10 @@ A simple would be::
     async def hello(request):
         return web.Response(body=b'Hello, world')
 
-    def create_app(loop):
+    async def test_hello(test_client, loop):
         app = web.Application(loop=loop)
         app.router.add_get('/', hello)
-        return app
-
-    async def test_hello(test_client):
-        client = await test_client(create_app)
+        client = await test_client(app)
         resp = await client.get('/')
         assert resp.status == 200
         text = await resp.text()
@@ -69,14 +66,11 @@ app test client::
         return web.Response(
             body='value: {}'.format(request.app['value']).encode())
 
-    def create_app(loop):
-        app = web.Application(loop=loop)
-        app.router.add_route('*', '/', previous)
-        return app
-
     @pytest.fixture
     def cli(loop, test_client):
-        return loop.run_until_complete(test_client(create_app))
+        app = web.Application(loop=loop)
+        app.router.add_get('/', hello)
+        return loop.run_until_complete(test_client(app))
 
     async def test_set_value(cli):
         resp = await cli.post('/', data={'value': 'foo'})

tests/test_pytest_plugin.py

@@ -5,6 +5,8 @@ def test_myplugin(testdir):
     testdir.makepyfile("""\
 import asyncio
 import pytest
+from unittest import mock
+
 from aiohttp import web
 
 pytest_plugins = 'aiohttp.pytest_plugin'
@@ -30,6 +32,17 @@ def test_hello(test_client):
     assert 'Hello, world' in text
 
 
+@asyncio.coroutine
+def test_hello_from_app(test_client, loop):
+    app = web.Application(loop=loop)
+    app.router.add_get('/', hello)
+    client = yield from test_client(app)
+    resp = yield from client.get('/')
+    assert resp.status == 200
+    text = yield from resp.text()
+    assert 'Hello, world' in text
+
+
 @asyncio.coroutine
 def test_hello_with_loop(test_client, loop):
     client = yield from test_client(create_app)
@@ -48,6 +61,27 @@ def test_hello_fails(test_client):
     assert 'Hello, wield' in text
 
 
+@asyncio.coroutine
+def test_hello_with_fake_loop(test_client):
+    with pytest.raises(AssertionError):
+        fake_loop = mock.Mock()
+        yield from test_client(web.Application(loop=fake_loop))
+
+
+@asyncio.coroutine
+def test_set_args(test_client, loop):
+    with pytest.raises(AssertionError):
+        app = web.Application(loop=loop)
+        yield from test_client(app, 1, 2, 3)
+
+
+@asyncio.coroutine
+def test_set_keyword_args(test_client, loop):
+    with pytest.raises(AssertionError):
+        app = web.Application(loop=loop)
+        yield from test_client(app, param=1)
+
+
 @asyncio.coroutine
 def test_noop():
     pass
@@ -111,4 +145,4 @@ def make_app(loop):
 
 """)
     result = testdir.runpytest('-p', 'no:sugar')
-    result.assert_outcomes(passed=7, failed=1)
+    result.assert_outcomes(passed=11, failed=1)