Fix port issue on host-based routing

docs/routing.md

@@ -183,9 +183,10 @@ url = app.url_path_for("user_detail", username=...)
 If you want to use different routes for the same path based on the `Host` header.
 
 Note that port is removed from the `Host` header when matching.
-For example, `Host (host='example.org:3600', ...)` will not be processed 
-even if the `Host` header is `example.org:3600`. 
-Therefore, specify only the domain or IP address
+For example, `Host (host='example.org:3600', ...)` will be processed 
+even if the `Host` header contains or does not contain a port other than `3600`
+(`example.org:5600`, `example.org`). 
+Therefore, you can specify the port if you need it for use in `url_for`.
 
 There are several ways to connect host-based routes to your application
 

starlette/routing.py

@@ -146,7 +146,7 @@ def compile_path(
         ending = "s" if len(duplicated_params) > 1 else ""
         raise ValueError(f"Duplicated param name{ending} {names} at path {path}")
 
-    path_regex += re.escape(path[idx:]) + "$"
+    path_regex += re.escape(path[idx:].split(":")[0]) + "$"
     path_format += path[idx:]
 
     return re.compile(path_regex), path_format, param_convertors

tests/test_routing.py

@@ -352,6 +352,11 @@ def users_api(request):
             name="api",
             app=Router([Route("/users", users_api, name="users")]),
         ),
+        Host(
+            "port.example.org:3600",
+            name="port",
+            app=Router([Route("/", homepage, name="homepage")]),
+        ),
     ]
 )
 
@@ -375,6 +380,21 @@ def test_host_routing(test_client_factory):
     response = client.get("/")
     assert response.status_code == 200
 
+    client = test_client_factory(mixed_hosts_app, base_url="https://port.example.org/")
+
+    response = client.get("/users")
+    assert response.status_code == 404
+
+    response = client.get("/")
+    assert response.status_code == 200
+
+    client = test_client_factory(
+        mixed_hosts_app, base_url="https://port.example.org:5600/"
+    )
+
+    response = client.get("/")
+    assert response.status_code == 200
+
 
 def test_host_reverse_urls():
     assert (
@@ -389,6 +409,12 @@ def test_host_reverse_urls():
         mixed_hosts_app.url_path_for("api:users").make_absolute_url("https://whatever")
         == "https://api.example.org/users"
     )
+    assert (
+        mixed_hosts_app.url_path_for("port:homepage").make_absolute_url(
+            "https://whatever"
+        )
+        == "https://port.example.org:3600/"
+    )
 
 
 async def subdomain_app(scope, receive, send):