Always show server location in ASGI (#2522)

Co-authored-by: Adam Hopkins <adam@amhopkins.com>
Co-authored-by: Zhiwei Liang <zhi.wei.liang@outlook.com>
Co-authored-by: Néstor Pérez <25409753+prryplatypus@users.noreply.github.com>

tests/test_asgi.py

@@ -546,3 +546,13 @@ async def test_signals_triggered(app):
     assert response.status_code == 200
     assert response.text == "test_signals_triggered"
     assert signals_triggered == signals_expected
+
+
+@pytest.mark.asyncio
+async def test_asgi_serve_location(app):
+    @app.get("/")
+    def _request(request: Request):
+        return text(request.app.serve_location)
+
+    _, response = await app.asgi_client.get("/")
+    assert response.text == "http://<ASGI>"

tests/test_http.py

@@ -2,6 +2,7 @@ import json as stdjson
 
 from collections import namedtuple
 from pathlib import Path
+from sys import version_info
 
 import pytest
 
@@ -74,7 +75,10 @@ def test_full_message(client):
         """
     )
     response = client.recv()
-    assert len(response) == 151
+
+    # AltSvcCheck touchup removes the Alt-Svc header from the
+    # response in the Python 3.9+ in this case
+    assert len(response) == (151 if version_info < (3, 9) else 140)
     assert b"200 OK" in response