Implement IntoResponse and IntoResponseParts for http::Extensions (#975)

* Implement `IntoResponse` and `IntoResponseParts` for `http::Extensions`

Requires a new release of `http`.

* remove http patch

* changelog ref

axum-core/src/response/into_response.rs

@@ -3,7 +3,7 @@ use crate::{body, BoxError};
 use bytes::{buf::Chain, Buf, Bytes, BytesMut};
 use http::{
     header::{self, HeaderMap, HeaderName, HeaderValue},
-    StatusCode,
+    Extensions, StatusCode,
 };
 use http_body::{
     combinators::{MapData, MapErr},
@@ -384,6 +384,14 @@ impl IntoResponse for HeaderMap {
     }
 }
 
+impl IntoResponse for Extensions {
+    fn into_response(self) -> Response {
+        let mut res = ().into_response();
+        *res.extensions_mut() = self;
+        res
+    }
+}
+
 impl<K, V, const N: usize> IntoResponse for [(K, V); N]
 where
     K: TryInto<HeaderName>,

axum-core/src/response/into_response_parts.rs

@@ -249,3 +249,12 @@ macro_rules! impl_into_response_parts {
 }
 
 all_the_tuples!(impl_into_response_parts);
+
+impl IntoResponseParts for Extensions {
+    type Error = Infallible;
+
+    fn into_response_parts(self, mut res: ResponseParts) -> Result<ResponseParts, Self::Error> {
+        res.extensions_mut().extend(self);
+        Ok(res)
+    }
+}