Fix compression

src/libraries/System.Net.WebSockets.Client/src/System/Net/WebSockets/ClientWebSocket.cs

@@ -148,6 +148,9 @@ public override Task SendAsync(ArraySegment<byte> buffer, WebSocketMessageType m
         public override ValueTask SendAsync(ReadOnlyMemory<byte> buffer, WebSocketMessageType messageType, bool endOfMessage, CancellationToken cancellationToken) =>
             ConnectedWebSocket.SendAsync(buffer, messageType, endOfMessage, cancellationToken);
 
+        public override ValueTask SendAsync(ReadOnlyMemory<byte> buffer, WebSocketMessageType messageType, WebSocketMessageFlags messageFlags, CancellationToken cancellationToken) =>
+            ConnectedWebSocket.SendAsync(buffer, messageType, messageFlags, cancellationToken);
+
         public override Task<WebSocketReceiveResult> ReceiveAsync(ArraySegment<byte> buffer, CancellationToken cancellationToken) =>
             ConnectedWebSocket.ReceiveAsync(buffer, cancellationToken);
 

src/libraries/System.Net.WebSockets.Client/tests/DeflateTests.cs

@@ -86,6 +86,53 @@ await LoopbackServer.CreateClientAndServerAsync(async uri =>
             }), new LoopbackServer.Options { WebSocketEndpoint = true });
         }
 
+        [ConditionalFact(nameof(WebSocketsSupported))]
+        public async Task ThrowWhenContinuationWithDifferentCompressionFlags()
+        {
+            await LoopbackServer.CreateClientAndServerAsync(async uri =>
+            {
+                using (var cws = new ClientWebSocket())
+                using (var cts = new CancellationTokenSource(TimeOutMilliseconds))
+                {
+                    cws.Options.DangerousDeflateOptions = new WebSocketDeflateOptions();
+                    await ConnectAsync(cws, uri, cts.Token);
+
+                    await cws.SendAsync(Memory<byte>.Empty, WebSocketMessageType.Text, WebSocketMessageFlags.DisableCompression, default);
+                    Assert.Throws<ArgumentException>("messageFlags", () =>
+                       cws.SendAsync(Memory<byte>.Empty, WebSocketMessageType.Binary, WebSocketMessageFlags.EndOfMessage, default));
+                }
+            }, server => server.AcceptConnectionAsync(async connection =>
+            {
+                Dictionary<string, string> headers = await LoopbackHelper.WebSocketHandshakeAsync(connection);
+            }), new LoopbackServer.Options { WebSocketEndpoint = true });
+        }
+
+        [ConditionalFact(nameof(WebSocketsSupported))]
+        public async Task SendHelloWithDisableCompression()
+        {
+            byte[] bytes = "Hello"u8.ToArray();
+            await LoopbackServer.CreateClientAndServerAsync(async uri =>
+            {
+                using (var cws = new ClientWebSocket())
+                using (var cts = new CancellationTokenSource(TimeOutMilliseconds))
+                {
+                    cws.Options.DangerousDeflateOptions = new WebSocketDeflateOptions();
+                    await ConnectAsync(cws, uri, cts.Token);
+
+                    WebSocketMessageFlags flags = WebSocketMessageFlags.DisableCompression | WebSocketMessageFlags.EndOfMessage;
+                    await cws.SendAsync(bytes, WebSocketMessageType.Text, flags, cts.Token);
+                }
+            }, server => server.AcceptConnectionAsync(async connection =>
+            {
+                var buffer = new byte[bytes.Length];
+                Dictionary<string, string> headers = await LoopbackHelper.WebSocketHandshakeAsync(connection);
+                using WebSocket websocket = WebSocket.CreateFromStream(connection.Stream, true, null, TimeSpan.FromSeconds(30));
+                Assert.True(websocket.State == WebSocketState.Open || websocket.State == WebSocketState.CloseSent);
+                await websocket.ReceiveAsync(new ArraySegment<byte>(buffer), CancellationToken.None);
+                Assert.Equal(bytes, buffer);
+            }), new LoopbackServer.Options { WebSocketEndpoint = true });
+        }
+
         private static string CreateDeflateOptionsHeader(WebSocketDeflateOptions options)
         {
             var builder = new StringBuilder();