Avalonia/tests/Perspex.Styling.UnitTests/SelectorTests_PropertyEquals.cs

// Copyright (c) The Perspex Project. All rights reserved.
// Licensed under the MIT license. See licence.md file in the project root for full license information.

using System.Linq;
using System.Reactive.Linq;
using System.Threading.Tasks;
using Perspex.Controls;
using Xunit;

namespace Perspex.Styling.UnitTests
{
    public class SelectorTests_PropertyEquals
    {
        [Fact]
        public async Task PropertyEquals_Matches_When_Property_Has_Matching_Value()
        {
            var control = new TextBlock();
            var target = new Selector().PropertyEquals(TextBlock.TextProperty, "foo");
            var activator = target.Match(control).ObservableResult;

            Assert.False(await activator.Take(1));
            control.Text = "foo";
            Assert.True(await activator.Take(1));
            control.Text = null;
            Assert.False(await activator.Take(1));
        }
    }
}