added example test of tcp connection for socks5 client

tests/sock5_client_test.rs

@@ -0,0 +1,46 @@
+use tokio::net::{TcpListener};
+use tokio::io::{self, AsyncReadExt, AsyncWriteExt};
+use std::time::Duration;
+use tokio::time::timeout;
+use tokio_test::assert_ok;
+use fast_socks5::client::{Config, Socks5Stream};
+
+#[tokio::test]
+async fn test_socks5_connection() -> io::Result<()> {
+    let socks_server = TcpListener::bind("127.0.0.1:0").await?;
+    let addr = socks_server.local_addr()?;
+
+    tokio::spawn(async move {
+        let (mut stream, _) = socks_server.accept().await.expect("Server accept failed");
+        let mut buf = [0u8; 100];
+
+        let bytes_read = stream.read(&mut buf).await.expect("Read initial handshake");
+        assert_eq!(&buf[..bytes_read], [0x05, 0x01, 0x00]);
+        stream.write_all(&[0x05, 0x00]).await.expect("Write handshake response");
+
+        let bytes_read = stream.read(&mut buf).await.expect("Read request");
+        assert_eq!(&buf[..bytes_read], &[0x05, 0x01, 0x00, 0x03, 0x05, b't', b'e', b'.', b's', b't', 0x00, 0x50]);
+        stream.write_all(&[0x05,0x00,0x00,0x01,0xff, 0x00,0x00,0x01,0x00,0x50]).await.expect("Write response");
+
+        let bytes_read = stream.read(&mut buf).await.expect("Read 'get' request");
+        assert_eq!(&buf[..bytes_read], &[b'g', b'e', b't']);
+        stream.write_all(b"all ok").await.expect("Write 'all ok'");
+        stream.shutdown().await.expect("Shutdown stream");
+    });
+
+    let mut socks_client = assert_ok!(Socks5Stream::connect(
+        addr,
+        "te.st".to_string(),
+        80,
+        Config::default()
+    ).await);
+    socks_client.write_all(b"get").await?;
+
+    let mut resp = String::new();
+    timeout(Duration::from_secs(1), async {
+        socks_client.read_to_string(&mut resp).await.expect("Read response");
+    }).await?;
+
+    assert_eq!(resp, "all ok");
+    Ok(())
+}