Avalonia/tests/Avalonia.Markup.UnitTests/Data/BindingTests_Source.cs

using Moq;
using Avalonia.Controls;
using Avalonia.Data;
using Avalonia.Markup.Data;
using Xunit;
using System.ComponentModel;
using System.Runtime.CompilerServices;
using Avalonia.UnitTests;

namespace Avalonia.Markup.UnitTests.Data
{
    public class BindingTests_Source : ScopedTestBase
    {
        [Fact]
        public void Source_Should_Be_Used()
        {
            var source = new Source { Foo = "foo" };
            var binding = new Binding { Source = source, Path = "Foo" };
            var target = new TextBlock();

            target.Bind(TextBlock.TextProperty, binding);

            Assert.Equal("foo", target.Text);
        }
        
        public class Source : INotifyPropertyChanged
        {
            private string? _foo;

            public string? Foo
            {
                get => _foo;
                set
                {
                    _foo = value;
                    RaisePropertyChanged();
                }
            }

            public event PropertyChangedEventHandler? PropertyChanged;

            private void RaisePropertyChanged([CallerMemberName] string prop = "")
            {
                PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(prop));
            }
        }
    }
}