Create requests-async based TestClient, remove aiohttp dependency, drop Python 3.5

Update all tests to be compatible with requests-async
Cleanup testing client changes with black and isort
Remove Python 3.5 and other meta doc cleanup
rename pyproject and fix pep517 error
Add black config to tox.ini
Cleanup tests and remove aiohttp
tox.ini change for easier development commands
Remove aiohttp from changelog and requirements
Cleanup imports and Makefile

sanic/testing.py

@@ -1,6 +1,9 @@
 from json import JSONDecodeError
 from socket import socket
 
+import requests_async as requests
+import websockets
+
 from sanic.exceptions import MethodNotSupported
 from sanic.log import logger
 from sanic.response import text
@@ -16,32 +19,41 @@ class SanicTestClient:
         self.app = app
         self.port = port
 
-    async def _local_request(self, method, url, cookies=None, *args, **kwargs):
-        import aiohttp
+    def get_new_session(self):
+        return requests.Session()
 
+    async def _local_request(self, method, url, *args, **kwargs):
         logger.info(url)
-        conn = aiohttp.TCPConnector(ssl=False)
-        async with aiohttp.ClientSession(
-            cookies=cookies, connector=conn
-        ) as session:
-            async with getattr(session, method.lower())(
-                url, *args, **kwargs
-            ) as response:
-                try:
-                    response.text = await response.text()
-                except UnicodeDecodeError:
-                    response.text = None
+        raw_cookies = kwargs.pop("raw_cookies", None)
+
+        if method == "websocket":
+            async with websockets.connect(url, *args, **kwargs) as websocket:
+                websocket.opened = websocket.open
+                return websocket
+        else:
+            async with self.get_new_session() as session:
 
                 try:
-                    response.json = await response.json()
-                except (
-                    JSONDecodeError,
-                    UnicodeDecodeError,
-                    aiohttp.ClientResponseError,
-                ):
+                    response = await getattr(session, method.lower())(
+                        url, verify=False, *args, **kwargs
+                    )
+                except NameError:
+                    raise Exception(response.status_code)
+
+                try:
+                    response.json = response.json()
+                except (JSONDecodeError, UnicodeDecodeError):
                     response.json = None
 
                 response.body = await response.read()
+                response.status = response.status_code
+                response.content_type = response.headers.get("content-type")
+
+                if raw_cookies:
+                    response.raw_cookies = {}
+                    for cookie in response.cookies:
+                        response.raw_cookies[cookie.name] = cookie
+
                 return response
 
     def _sanic_endpoint_test(
@@ -83,11 +95,15 @@ class SanicTestClient:
             server_kwargs = dict(sock=sock, **server_kwargs)
             host, port = sock.getsockname()
 
-        if uri.startswith(("http:", "https:", "ftp:", "ftps://", "//")):
+        if uri.startswith(
+            ("http:", "https:", "ftp:", "ftps://", "//", "ws:", "wss:")
+        ):
             url = uri
         else:
-            url = "http://{host}:{port}{uri}".format(
-                host=host, port=port, uri=uri
+            uri = uri if uri.startswith("/") else "/{uri}".format(uri=uri)
+            scheme = "ws" if method == "websocket" else "http"
+            url = "{scheme}://{host}:{port}{uri}".format(
+                scheme=scheme, host=host, port=port, uri=uri
             )
 
         @self.app.listener("after_server_start")
@@ -146,3 +162,6 @@ class SanicTestClient:
 
     def head(self, *args, **kwargs):
         return self._sanic_endpoint_test("head", *args, **kwargs)
+
+    def websocket(self, *args, **kwargs):
+        return self._sanic_endpoint_test("websocket", *args, **kwargs)