Stylet/StyletUnitTests/ActionExtensionTests.cs

using Moq;
using NUnit.Framework;
using Stylet;
using Stylet.Xaml;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Markup;

namespace StyletUnitTests
{
    [TestFixture, RequiresSTA]
    public class ActionExtensionTests
    {
        private ActionExtension actionExtension;
        private Mock<IProvideValueTarget> provideValueTarget;
        private Mock<IServiceProvider> serviceProvider;

        [SetUp]
        public void SetUp()
        {
            this.actionExtension = new ActionExtension("MethodName");

            this.provideValueTarget = new Mock<IProvideValueTarget>();
            this.provideValueTarget.Setup(x => x.TargetObject).Returns(new FrameworkElement());

            this.serviceProvider = new Mock<IServiceProvider>();
            serviceProvider.Setup(x => x.GetService(typeof(IProvideValueTarget))).Returns(provideValueTarget.Object);
        }

        [Test]
        public void ReturnsThisIfTargetObjectIsNotFrameworkElement()
        {
            this.provideValueTarget.Setup(x => x.TargetObject).Returns(null);

            Assert.AreEqual(this.actionExtension, this.actionExtension.ProvideValue(this.serviceProvider.Object));
        }

        [Test]
        public void ReturnsCommandActionIfTargetObjectPropertyTypeIsICommand()
        {
            // This will be asked for the IViewManager, which we don't care about for now
            IoC.GetInstance = (t, k) => null;
            this.provideValueTarget.Setup(x => x.TargetProperty).Returns(Button.CommandProperty);

            object value = this.actionExtension.ProvideValue(this.serviceProvider.Object);
            Assert.IsInstanceOf<CommandAction>(value);

            var action = (CommandAction)value;

            Assert.AreEqual(action.Subject, this.provideValueTarget.Object.TargetObject);
            Assert.AreEqual("MethodName", action.MethodName);
        }

        [Test]
        public void ReturnsEventActionIfTargetObjectPropertyIsEventInfo()
        {
            this.provideValueTarget.Setup(x => x.TargetProperty).Returns(typeof(Button).GetEvent("Click"));

            Assert.IsInstanceOf<RoutedEventHandler>(this.actionExtension.ProvideValue(this.serviceProvider.Object));
        }

        [Test]
        public void ThrowsArgumentExceptionIfTargetObjectNotDependencyPropertyOrEventInfo()
        {
            this.provideValueTarget.Setup(x => x.TargetProperty).Returns(5);

            Assert.Throws<ArgumentException>(() => this.actionExtension.ProvideValue(this.serviceProvider.Object));
        }
    }
}