test: add tests for command and event.

tests/HeadlessTest.Ursa/Controls/PaginationTests/PaginationTests.cs

@@ -1,9 +1,11 @@
 using Avalonia;
 using Avalonia.Controls;
+using Avalonia.Data;
 using Avalonia.Headless.XUnit;
 using Avalonia.Interactivity;
 using Avalonia.Markup.Xaml.MarkupExtensions;
 using Avalonia.Threading;
+using CommunityToolkit.Mvvm.Input;
 using HeadlessTest.Ursa.TestHelpers;
 using Ursa.Controls;
 
@@ -276,4 +278,158 @@ public class PaginationTests
         Assert.Equal(50, pagination.PageSize);
         Assert.Equal(1, pagination.CurrentPage);
     }
+    
+    [AvaloniaFact]
+    public void Click_On_Previews_Or_Next_Triggers_Command()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+            Command = new RelayCommand(() => count++)
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var previousButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_PreviousButton);
+        var nextButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_NextButton);
+        previousButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, count);
+        nextButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Assert.Equal(2, count);
+        Dispatcher.UIThread.RunJobs();
+    }
+    
+    [AvaloniaFact]
+    public void Click_On_Previews_Or_Next_Triggers_Command_With_Parameter()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+            Command = new RelayCommand<int>(page => count = page),
+            [!Pagination.CommandParameterProperty] = new Binding(nameof(Pagination.CurrentPage))
+                { RelativeSource = new RelativeSource(RelativeSourceMode.Self) },
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var previousButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_PreviousButton);
+        var nextButton = pagination.GetTemplateChildOfType<Button>(Pagination.PART_NextButton);
+        previousButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(2, count);
+        nextButton?.RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(3, count);
+    }
+
+    [AvaloniaFact]
+    public void Buttons_Panel_Is_Correct_Case1()
+    {
+        var window = new Window();
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var buttonsPanel = pagination.GetTemplateChildOfType<Panel>(Pagination.PART_ButtonPanel);
+        Assert.NotNull(buttonsPanel);
+        Assert.Equal(6, buttonsPanel.Children.Count(a => a.IsVisible));
+
+        pagination.TotalCount = 30000;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(7, buttonsPanel.Children.Count(a => a.IsVisible));
+        
+        var buttons = buttonsPanel.Children.OfType<PaginationButton>().ToList();
+        Assert.Equal(1, buttons[0].Page);
+        Assert.Equal(2, buttons[1].Page);
+        Assert.Equal(3, buttons[2].Page);
+        Assert.Equal(4, buttons[3].Page);
+        Assert.Equal(5, buttons[4].Page);
+        Assert.True(buttons[5].IsFastBackward);
+        Assert.Equal(600, buttons[6].Page);
+        
+        pagination.CurrentPage = 300;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(7, buttonsPanel.Children.Count(a => a.IsVisible));
+        Assert.Equal(1, buttons[0].Page);
+        Assert.True(buttons[1].IsFastForward);
+        Assert.Equal(299, buttons[2].Page);
+        Assert.Equal(300, buttons[3].Page);
+        Assert.Equal(301, buttons[4].Page);
+        Assert.True(buttons[5].IsFastBackward);
+        Assert.Equal(600, buttons[6].Page);
+        
+        pagination.CurrentPage = 600;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(7, buttonsPanel.Children.Count(a => a.IsVisible));
+        Assert.Equal(1, buttons[0].Page);
+        Assert.True(buttons[1].IsFastForward);
+        Assert.Equal(596, buttons[2].Page);
+        Assert.Equal(597, buttons[3].Page);
+        Assert.Equal(598, buttons[4].Page);
+        Assert.Equal(599, buttons[5].Page);
+        Assert.Equal(600, buttons[6].Page);
+
+    }
+
+    [AvaloniaFact]
+    public void Button_Panel_Button_Triggers_Command()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+            Command = new RelayCommand<int>(page => count = page),
+            [!Pagination.CommandParameterProperty] = new Binding(nameof(Pagination.CurrentPage))
+                { RelativeSource = new RelativeSource(RelativeSourceMode.Self) },
+        };
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        var buttonsPanel = pagination.GetTemplateChildOfType<Panel>(Pagination.PART_ButtonPanel);
+        var buttons = buttonsPanel.Children.OfType<PaginationButton>().ToList();
+        buttons[0].RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, count);
+        buttons[1].RaiseEvent(new RoutedEventArgs(Button.ClickEvent));
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(2, count);
+    }
+
+    [AvaloniaFact]
+    public void Change_CurrentPage_Triggers_Event()
+    {
+        var window = new Window();
+        int count = 0;
+        var pagination = new Pagination
+        {
+            CurrentPage = 3,
+            PageSize = 50,
+            TotalCount = 300,
+        };
+        pagination.CurrentPageChanged += (sender, args) => count++;
+        window.Content = pagination;
+        window.Show();
+        Dispatcher.UIThread.RunJobs();
+        pagination.CurrentPage = 5;
+        Dispatcher.UIThread.RunJobs();
+        Assert.Equal(1, count);
+    }
+    
 }