Change HttpParserError process

tests/test_bad_request.py

@@ -0,0 +1,20 @@
+import asyncio
+from sanic import Sanic
+
+
+def test_bad_request_response():
+    app = Sanic('test_bad_request_response')
+    lines = []
+    async def _request(sanic, loop):
+        connect = asyncio.open_connection('127.0.0.1', 42101)
+        reader, writer = await connect
+        writer.write(b'not http')
+        while True:
+            line = await reader.readline()
+            if not line:
+                break
+            lines.append(line)
+        app.stop()
+    app.run(host='127.0.0.1', port=42101, debug=False, after_start=_request)
+    assert lines[0] == b'HTTP/1.1 400 Bad Request\r\n'
+    assert lines[-1] == b'Error: Bad Request'