public void Binding_ContentTemplate_After_Content_Does_Not_Leave_Orpaned_TextBlock()
{
// Test for #1271.
var children = new List <IControl>();
var presenter = new ContentPresenter();
// The content and then the content template property need to be bound with delayed bindings
// as they are in Avalonia.Markup.Xaml.
DelayedBinding.Add(presenter, ContentPresenter.ContentProperty, new Binding("Content")
{
Priority = BindingPriority.TemplatedParent,
RelativeSource = new RelativeSource(RelativeSourceMode.TemplatedParent),
});
DelayedBinding.Add(presenter, ContentPresenter.ContentTemplateProperty, new Binding("ContentTemplate")
{
Priority = BindingPriority.TemplatedParent,
RelativeSource = new RelativeSource(RelativeSourceMode.TemplatedParent),
});
presenter.GetObservable(ContentPresenter.ChildProperty).Subscribe(children.Add);
var target = new ContentControl
{
Template = new FuncControlTemplate <ContentControl>(_ => presenter),
ContentTemplate = new FuncDataTemplate <string>(x => new Canvas()),
Content = "foo",
};
// The control must be rooted.
var root = new TestRoot
{
Child = target,
};
target.ApplyTemplate();
// When the template is applied, the Content property is bound before the ContentTemplate
// property, causing a TextBlock to be created by the default template before ContentTemplate
// is bound.
Assert.Collection(
children,
x => Assert.Null(x),
x => Assert.IsType <TextBlock>(x),
x => Assert.IsType <Canvas>(x));
var textBlock = (TextBlock)children[1];
// The leak in #1271 was caused by the TextBlock's logical parent not being cleared when
// it is replaced by the Canvas.
Assert.Null(textBlock.GetLogicalParent());
}