DRYing up the test suite using pytest fixtures (#2306)

* add fixtures to conftest.py

* use fixtures in test_appctx.py

* use fixtures in test_blueprints.py

* use fixtures in test_depreciations.py

* use fixtures in test_regressions.py

* use fixtures in test_reqctx.py

* use fixtures in test_templating.py

* use fixtures in test_user_error_handler.py

* use fixtures in test_views.py

* use fixtures in test_basics.py

* use fixtures in test_helpers.py

* use fixtures in test_testing.py

* update conftest.py

* make docstrings  PEP-257 compliant

* cleanup

* switch dictonary format

* use pytest parameterization for test_json_as_unicode

tests/test_views.py

@@ -16,6 +16,7 @@ import flask.views
 
 from werkzeug.http import parse_set_header
 
+
 def common_test(app):
     c = app.test_client()
 
@@ -25,23 +26,23 @@ def common_test(app):
     meths = parse_set_header(c.open('/', method='OPTIONS').headers['Allow'])
     assert sorted(meths) == ['GET', 'HEAD', 'OPTIONS', 'POST']
 
-def test_basic_view():
-    app = flask.Flask(__name__)
 
+def test_basic_view(app):
     class Index(flask.views.View):
         methods = ['GET', 'POST']
+
         def dispatch_request(self):
             return flask.request.method
 
     app.add_url_rule('/', view_func=Index.as_view('index'))
     common_test(app)
 
-def test_method_based_view():
-    app = flask.Flask(__name__)
 
+def test_method_based_view(app):
     class Index(flask.views.MethodView):
         def get(self):
             return 'GET'
+
         def post(self):
             return 'POST'
 
@@ -49,18 +50,19 @@ def test_method_based_view():
 
     common_test(app)
 
-def test_view_patching():
-    app = flask.Flask(__name__)
 
+def test_view_patching(app):
     class Index(flask.views.MethodView):
         def get(self):
             1 // 0
+
         def post(self):
             1 // 0
 
     class Other(Index):
         def get(self):
             return 'GET'
+
         def post(self):
             return 'POST'
 
@@ -69,12 +71,12 @@ def test_view_patching():
     app.add_url_rule('/', view_func=view)
     common_test(app)
 
-def test_view_inheritance():
-    app = flask.Flask(__name__)
 
+def test_view_inheritance(app):
     class Index(flask.views.MethodView):
         def get(self):
             return 'GET'
+
         def post(self):
             return 'POST'
 
@@ -88,18 +90,19 @@ def test_view_inheritance():
     meths = parse_set_header(c.open('/', method='OPTIONS').headers['Allow'])
     assert sorted(meths) == ['DELETE', 'GET', 'HEAD', 'OPTIONS', 'POST']
 
-def test_view_decorators():
-    app = flask.Flask(__name__)
 
+def test_view_decorators(app):
     def add_x_parachute(f):
         def new_function(*args, **kwargs):
             resp = flask.make_response(f(*args, **kwargs))
             resp.headers['X-Parachute'] = 'awesome'
             return resp
+
         return new_function
 
     class Index(flask.views.View):
         decorators = [add_x_parachute]
+
         def dispatch_request(self):
             return 'Awesome'
 
@@ -109,11 +112,13 @@ def test_view_decorators():
     assert rv.headers['X-Parachute'] == 'awesome'
     assert rv.data == b'Awesome'
 
+
 def test_view_provide_automatic_options_attr():
     app = flask.Flask(__name__)
 
     class Index1(flask.views.View):
         provide_automatic_options = False
+
         def dispatch_request(self):
             return 'Hello World!'
 
@@ -127,6 +132,7 @@ def test_view_provide_automatic_options_attr():
     class Index2(flask.views.View):
         methods = ['OPTIONS']
         provide_automatic_options = True
+
         def dispatch_request(self):
             return 'Hello World!'
 
@@ -146,9 +152,8 @@ def test_view_provide_automatic_options_attr():
     rv = c.open('/', method='OPTIONS')
     assert 'OPTIONS' in rv.allow
 
-def test_implicit_head():
-    app = flask.Flask(__name__)
 
+def test_implicit_head(app):
     class Index(flask.views.MethodView):
         def get(self):
             return flask.Response('Blub', headers={
@@ -164,12 +169,12 @@ def test_implicit_head():
     assert rv.data == b''
     assert rv.headers['X-Method'] == 'HEAD'
 
-def test_explicit_head():
-    app = flask.Flask(__name__)
 
+def test_explicit_head(app):
     class Index(flask.views.MethodView):
         def get(self):
             return 'GET'
+
         def head(self):
             return flask.Response('', headers={'X-Method': 'HEAD'})
 
@@ -181,12 +186,13 @@ def test_explicit_head():
     assert rv.data == b''
     assert rv.headers['X-Method'] == 'HEAD'
 
-def test_endpoint_override():
-    app = flask.Flask(__name__)
+
+def test_endpoint_override(app):
     app.debug = True
 
     class Index(flask.views.View):
         methods = ['GET', 'POST']
+
         def dispatch_request(self):
             return flask.request.method
 
@@ -198,9 +204,8 @@ def test_endpoint_override():
     # But these tests should still pass. We just log a warning.
     common_test(app)
 
-def test_multiple_inheritance():
-    app = flask.Flask(__name__)
 
+def test_multiple_inheritance(app):
     class GetView(flask.views.MethodView):
         def get(self):
             return 'GET'
@@ -219,9 +224,8 @@ def test_multiple_inheritance():
     assert c.delete('/').data == b'DELETE'
     assert sorted(GetDeleteView.methods) == ['DELETE', 'GET']
 
-def test_remove_method_from_parent():
-    app = flask.Flask(__name__)
 
+def test_remove_method_from_parent(app):
     class GetView(flask.views.MethodView):
         def get(self):
             return 'GET'