Add AsyncDisposableExtensions

PowerKit.Tests/AsyncDisposableExtensionsTests.cs

@@ -0,0 +1,56 @@
+using System;
+using System.Threading.Tasks;
+using FluentAssertions;
+using PowerKit.Extensions;
+using Xunit;
+
+namespace PowerKit.Tests;
+
+file class AsyncDisposableStub(Action onDispose) : IDisposable, IAsyncDisposable
+{
+    public void Dispose() => throw new Exception("DisposeAsync() should've been called instead");
+
+    public ValueTask DisposeAsync()
+    {
+        onDispose();
+        return default;
+    }
+}
+
+file class DisposableStub(Action onDispose) : IDisposable
+{
+    public void Dispose() => onDispose();
+}
+
+public class AsyncDisposableExtensionsTests
+{
+    [Fact]
+    public async Task ToAsyncDisposable_IAsyncDisposable_Test()
+    {
+        // Arrange
+        var asyncDisposeCalled = false;
+
+        var disposable = new AsyncDisposableStub(() => asyncDisposeCalled = true);
+
+        // Act
+        await disposable.ToAsyncDisposable().DisposeAsync();
+
+        // Assert
+        asyncDisposeCalled.Should().BeTrue();
+    }
+
+    [Fact]
+    public async Task ToAsyncDisposable_IDisposable_Test()
+    {
+        // Arrange
+        var disposeCalled = false;
+
+        var disposable = new DisposableStub(() => disposeCalled = true);
+
+        // Act
+        await disposable.ToAsyncDisposable().DisposeAsync();
+
+        // Assert
+        disposeCalled.Should().BeTrue();
+    }
+}

PowerKit/Extensions/AsyncDisposableExtensions.cs

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+#if NET40_OR_GREATER || NETSTANDARD || NET
+#nullable enable
+using System;
+using System.Diagnostics.CodeAnalysis;
+using System.Threading.Tasks;
+
+namespace PowerKit.Extensions;
+
+// Provides a dynamic and uniform way to deal with async disposable.
+// Used as an abstraction to dynamically polyfill IAsyncDisposable implementations in BCL types. For example:
+// - Stream class on .NET Framework 4.6.1 -> calls Dispose()
+// - Stream class on .NET Core 3.0 -> calls DisposeAsync()
+// - Stream class on .NET Standard 2.0 -> calls DisposeAsync() or Dispose(), depending on the runtime
+file class AsyncDisposableAdapter(IDisposable target) : IAsyncDisposable
+{
+    public async ValueTask DisposeAsync()
+    {
+        if (target is IAsyncDisposable asyncDisposable)
+        {
+            await asyncDisposable.DisposeAsync().ConfigureAwait(false);
+        }
+        else
+        {
+            target.Dispose();
+        }
+    }
+}
+
+#if !POWERKIT_INCLUDE_COVERAGE
+[ExcludeFromCodeCoverage]
+#endif
+internal static class AsyncDisposableExtensions
+{
+    extension(IDisposable disposable)
+    {
+        /// <summary>
+        /// Wraps the disposable in an <see cref="IAsyncDisposable" /> adapter that calls
+        /// <see cref="IAsyncDisposable.DisposeAsync" /> if supported, or falls back to
+        /// <see cref="IDisposable.Dispose" />.
+        /// </summary>
+        public IAsyncDisposable ToAsyncDisposable() =>
+            disposable is IAsyncDisposable asyncDisposable
+                ? asyncDisposable
+                : new AsyncDisposableAdapter(disposable);
+    }
+}
+#endif