chore: import upstream snapshot with attribution

dotnet/tests/Microsoft.Agents.AI.Workflows.Declarative.UnitTests/TestOutputAdapter.cs

@@ -0,0 +1,72 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text;
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.Agents.AI.Workflows.Declarative.UnitTests;
+
+public sealed class TestOutputAdapter(ITestOutputHelper output) : TextWriter, ILogger, ILoggerFactory
+{
+    private readonly Stack<string> _scopes = [];
+
+    public override Encoding Encoding { get; } = Encoding.UTF8;
+
+    public void AddProvider(ILoggerProvider provider) => throw new NotSupportedException();
+
+    public ILogger CreateLogger(string categoryName) => this;
+
+    public bool IsEnabled(LogLevel logLevel) => true;
+
+    public override void WriteLine(object? value) => this.SafeWrite($"{value}");
+
+    public override void WriteLine(string? format, params object?[] arg) => this.SafeWrite(string.Format(format ?? string.Empty, arg));
+
+    public override void WriteLine(string? value) => this.SafeWrite(value ?? string.Empty);
+
+    public override void Write(object? value) => this.SafeWrite($"{value}");
+
+    public override void Write(char[]? buffer) => this.SafeWrite(new string(buffer));
+
+    public IDisposable BeginScope<TState>(TState state) where TState : notnull
+    {
+        this._scopes.Push($"{state}");
+        return new LoggerScope(() => this._scopes.Pop());
+    }
+
+    public void Log<TState>(LogLevel logLevel, EventId eventId, TState state, Exception? exception, Func<TState, Exception?, string> formatter)
+    {
+        string message = formatter(state, exception);
+        string scope = this._scopes.Count > 0 ? $"[{this._scopes.Peek()}] " : string.Empty;
+        output.WriteLine($"{scope}{message}");
+    }
+
+    private void SafeWrite(string value)
+    {
+        try
+        {
+            output.WriteLine(value ?? string.Empty);
+        }
+        catch (InvalidOperationException exception) when (exception.Message == "There is no currently active test.")
+        {
+            // This exception is thrown when the test output is accessed outside of a test context.
+            // We can ignore it since we are not in a test context.
+        }
+    }
+
+    private sealed class LoggerScope(Action action) : IDisposable
+    {
+        private bool _disposed;
+
+        public void Dispose()
+        {
+            if (!this._disposed)
+            {
+                action.Invoke();
+                this._disposed = true;
+            }
+        }
+    }
+}