add tests for windows named pipes

Author: ekump

libdd-http-client/tests/windows_named_pipe.rs

@@ -0,0 +1,58 @@
+// Copyright 2026-Present Datadog, Inc. https://www.datadoghq.com/
+// SPDX-License-Identifier: Apache-2.0
+
+#![cfg(windows)]
+
+use libdd_http_client::{HttpClient, HttpMethod, HttpRequest};
+use std::time::Duration;
+use tokio::io::{AsyncReadExt, AsyncWriteExt};
+use tokio::net::windows::named_pipe::ServerOptions;
+
+#[cfg_attr(miri, ignore)]
+#[tokio::test]
+async fn test_named_pipe_round_trip() {
+    let pipe_name = format!(
+        r"\\.\pipe\dd_http_client_test_{}_{}",
+        std::process::id(),
+        fastrand::u64(..)
+    );
+
+    let server = ServerOptions::new()
+        .first_pipe_instance(true)
+        .create(&pipe_name)
+        .unwrap();
+
+    let pipe_name_clone = pipe_name.clone();
+    tokio::spawn(async move {
+        server.connect().await.unwrap();
+        let mut buf = vec![0u8; 1024];
+        let _ = server.read(&mut buf).await.unwrap();
+        server
+            .write_all(b"HTTP/1.1 200 OK\r\nContent-Length: 2\r\n\r\nok")
+            .await
+            .unwrap();
+    });
+
+    let client = HttpClient::builder()
+        .base_url("http://localhost".to_owned())
+        .timeout(Duration::from_secs(5))
+        .windows_named_pipe(&pipe_name_clone)
+        .build()
+        .unwrap();
+
+    let req = HttpRequest::new(HttpMethod::Get, "http://localhost/ping".to_owned());
+    let response = client.send(req).await.unwrap();
+
+    assert_eq!(response.status_code, 200);
+    assert_eq!(response.body.as_ref(), b"ok");
+}
+
+#[test]
+fn test_named_pipe_client_constructs() {
+    let client = HttpClient::builder()
+        .base_url("http://localhost".to_owned())
+        .timeout(Duration::from_secs(5))
+        .windows_named_pipe(r"\\.\pipe\dd_test_construct")
+        .build();
+    assert!(client.is_ok());
+}