maui-linux/Xamarin.Forms.Core.UnitTests/EffectTests.cs

using System;
using NUnit.Framework;

using System.Collections.Generic;
using System.Linq;

namespace Xamarin.Forms.Core.UnitTests
{
	[TestFixture]
	public class EffectTests : BaseTestFixture
	{
		[Test]
		public void ResolveSetsId ()
		{
			string id = "Unknown";
			var effect = Effect.Resolve (id);
			Assert.AreEqual (id, effect.ResolveId);
		}

		[Test]
		public void UnknownIdReturnsNullEffect ()
		{
			var effect = Effect.Resolve ("Foo");
			Assert.IsInstanceOf<NullEffect> (effect);
		}

		[Test]
		public void SendAttachedSetsFlag ()
		{
			var effect = Effect.Resolve ("Foo");
			effect.SendAttached ();
			Assert.True (effect.IsAttached);
		}

		[Test]
		public void SendDetachedUnsetsFlag ()
		{
			var effect = Effect.Resolve ("Foo");
			effect.SendAttached ();
			effect.SendDetached ();
			Assert.False (effect.IsAttached);
		}

		[Test]
		public void EffectLifecyclePreProvider ()
		{
			var effect = new CustomEffect ();
			var element = new Label ();

			element.Effects.Add (effect);
			((IVisualElementController)element).EffectControlProvider = new EffectControlProvider ();

			Assert.True (effect.IsAttached);
			Assert.True (effect.OnAttachedCalled);
			Assert.True (effect.Registered);
			Assert.False (effect.OnDetachedCalled);

			element.Effects.Remove (effect);
			Assert.True (effect.OnDetachedCalled);
		}

		[Test]
		public void EffectLifecyclePostProvider ()
		{
			var effect = new CustomEffect ();
			var element = new Label ();

			((IVisualElementController)element).EffectControlProvider = new EffectControlProvider ();
			element.Effects.Add (effect);

			Assert.True (effect.IsAttached);
			Assert.True (effect.OnAttachedCalled);
			Assert.True (effect.Registered);
			Assert.False (effect.OnDetachedCalled);

			element.Effects.Remove (effect);
			Assert.True (effect.OnDetachedCalled);
		}

		[Test]
		public void EffectsClearDetachesEffect ()
		{
			var effect = new CustomEffect ();
			var element = new Label ();

			((IVisualElementController)element).EffectControlProvider = new EffectControlProvider ();
			element.Effects.Add (effect);

			element.Effects.Clear ();

			Assert.True (effect.OnDetachedCalled);
		}

		class EffectControlProvider : IEffectControlProvider
		{
			public void RegisterEffect (Effect effect)
			{
				var e = effect as CustomEffect;
				if (e != null)
					e.Registered = true;
			}
		}

		class CustomEffect : Effect
		{
			public bool OnAttachedCalled;
			public bool OnDetachedCalled;
			public bool Registered;

			protected override void OnAttached ()
			{
				OnAttachedCalled = true;
			}

			protected override void OnDetached ()
			{
				OnDetachedCalled = true;
			}
		}
	}	
}