Added InitDispose class.

Author: igor-tkachev

CodeJam.Main.Tests/DisposableTests.cs

@@ -125,5 +125,71 @@ public static void TestParameterizedAnonymousDisposable()
 			Assert.IsTrue(disposed);
 			Assert.AreEqual("state", state);
 		}
+
+		[Test]
+		public static void InitDisposeTest1()
+		{
+			var i = 0;
+
+			using (InitDispose.Create(
+				() => Assert.That(++i, Is.EqualTo(1)),
+				() => Assert.That(++i, Is.EqualTo(3))))
+			{
+				Assert.That(++i, Is.EqualTo(2));
+			}
+
+			Assert.That(++i, Is.EqualTo(4));
+		}
+
+		[Test]
+		public static void InitDisposeTest2()
+		{
+			var i = 0;
+
+			using (InitDispose.Create(
+				() => Assert.That(++i, Is.EqualTo(1).Or.EqualTo(3))))
+			{
+				Assert.That(++i, Is.EqualTo(2));
+			}
+
+			Assert.That(++i, Is.EqualTo(4));
+		}
+
+		[Test]
+		public static void InitDisposeTest3()
+		{
+			var i = 0;
+
+			using (InitDispose.Create(
+				isInit => Assert.That(i += isInit ? 1 : 2, Is.EqualTo(1).Or.EqualTo(4))))
+			{
+				Assert.That(++i, Is.EqualTo(2));
+			}
+
+			Assert.That(++i, Is.EqualTo(5));
+		}
+
+		[Test]
+		public static void InitDisposeTest4()
+		{
+			var i = 0;
+
+			using (InitDispose.Create(
+				() =>
+				{
+					Assert.That(++i, Is.EqualTo(1));
+					return "123";
+				},
+				s =>
+				{
+					Assert.That(++i, Is.EqualTo(3));
+					Assert.That(s,   Is.EqualTo("123"));
+				}))
+			{
+				Assert.That(++i, Is.EqualTo(2));
+			}
+
+			Assert.That(++i, Is.EqualTo(4));
+		}
 	}
-}
+}

CodeJam.Main/InitDispose.cs

@@ -0,0 +1,87 @@
+using System;
+
+using JetBrains.Annotations;
+
+namespace CodeJam
+{
+	/// <summary>Helper methods for <see cref="IDisposable"/></summary>
+	[PublicAPI]
+	public static class InitDispose
+	{
+		/// <summary>
+		/// Calls <paramref name="initAction"/> and
+		/// creates <see cref="IDisposable"/> instance that calls <paramref name="disposeAction"/> on disposing.
+		/// </summary>
+		/// <param name="initAction">The init action.</param>
+		/// <param name="disposeAction">The dispose action.</param>
+		/// <returns>
+		/// Instance of <see cref="IDisposable"/> that calls <paramref name="disposeAction"/> on disposing.
+		/// </returns>
+		[NotNull, Pure]
+		public static IDisposable Create([NotNull] Action initAction, [NotNull] Action disposeAction)
+		{
+			Code.NotNull(initAction,    nameof(initAction));
+			Code.NotNull(disposeAction, nameof(disposeAction));
+
+			initAction();
+			return Disposable.Create(disposeAction);
+		}
+
+		/// <summary>
+		/// Calls <paramref name="initAction"/> and
+		/// creates <see cref="IDisposable"/> instance that calls <paramref name="disposeAction"/> on disposing.
+		/// </summary>
+		/// <param name="initAction">The init action.</param>
+		/// <param name="disposeAction">The dispose action.</param>
+		/// <returns>
+		/// Instance of <see cref="IDisposable"/> that calls <paramref name="disposeAction"/> on disposing.
+		/// </returns>
+		[NotNull, Pure]
+		public static IDisposable Create<T>([NotNull] Func<T> initAction, [NotNull] Action<T> disposeAction)
+		{
+			Code.NotNull(initAction,    nameof(initAction));
+			Code.NotNull(disposeAction, nameof(disposeAction));
+
+			var initState = initAction();
+			return Disposable.Create(disposeAction, initState);
+		}
+
+		/// <summary>
+		/// Calls <paramref name="initDisposeAction"/> and
+		/// creates <see cref="IDisposable"/> instance that calls <paramref name="initDisposeAction"/> on disposing.
+		/// </summary>
+		/// <param name="initDisposeAction">The init and dispose action.</param>
+		/// <returns>
+		/// Instance of <see cref="IDisposable"/> that calls <paramref name="initDisposeAction"/> on disposing.
+		/// </returns>
+		[NotNull, Pure]
+		public static IDisposable Create([NotNull] Action initDisposeAction)
+		{
+			Code.NotNull(initDisposeAction,    nameof(initDisposeAction));
+
+			initDisposeAction();
+			return Disposable.Create(initDisposeAction);
+		}
+
+		/// <summary>
+		/// Calls <paramref name="initDisposeAction"/> and
+		/// creates <see cref="IDisposable"/> instance that calls <paramref name="initDisposeAction"/> on disposing.
+		/// </summary>
+		/// <param name="initDisposeAction">
+		/// The init and dispose action.
+		/// <paramref name="initDisposeAction"/> takes true if this is initAction.
+		/// It takes false if this is disposeAction.
+		/// </param>
+		/// <returns>
+		/// Instance of <see cref="IDisposable"/> that calls <paramref name="initDisposeAction"/> on disposing.
+		/// </returns>
+		[NotNull, Pure]
+		public static IDisposable Create([NotNull] Action<bool> initDisposeAction)
+		{
+			Code.NotNull(initDisposeAction,    nameof(initDisposeAction));
+
+			initDisposeAction(true);
+			return Disposable.Create<bool>(initDisposeAction, false);
+		}
+	}
+}