A:初版

test/NetClient.Test/TestDoubles/StaticTokenProvider.cs

@@ -0,0 +1,18 @@
+using System.Threading;
+using System.Threading.Tasks;
+using NetClient.Abstractions;
+
+namespace NetClient.Test.TestDoubles;
+
+public sealed class StaticTokenProvider : IAccessTokenProvider
+{
+    private readonly string? _token;
+
+    public StaticTokenProvider(string? token)
+    {
+        _token = token;
+    }
+
+    public Task<string?> GetTokenAsync(CancellationToken cancellationToken = default) => Task.FromResult(_token);
+}
+