Merge branch '57-when-auto-cond-req-304-responses-have-content-length-0' into h

Author: zefir-git

src/response/EmptyResponse.ts

@@ -16,8 +16,8 @@ export class EmptyResponse<A> extends Response<A> {
     }
 
     protected override async send(res: http.ServerResponse, req?: Request<A>): Promise<void> {
-        if (req !== undefined)
-            req._responseHeaders.set("content-length", "0");
+        if (!this.headers.has("content-length"))
+            this.headers.set("content-length", "0");
         this.writeHead(res, req);
         res.end();
     }