Initial BinaryLane v2 API client

tests/BinaryLane.Api.Tests/HttpClientTestHandler.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace BinaryLane.Api.Tests;
+
+internal sealed class HttpClientTestHandler : HttpMessageHandler
+{
+    private readonly Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> _send;
+
+    public HttpClientTestHandler(Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> send) =>
+        _send = send ?? throw new ArgumentNullException(nameof(send));
+
+    protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) =>
+        _send(request, cancellationToken);
+}