Merge pull request #4083 from icsharpcode/test-harness/idle-and-click

Synchronize headless UI tests on idle and hit-tested clicks

ILSpy.Tests/Analyzers/AnalyzerTreeKeyboardTests.cs

@@ -154,12 +154,7 @@ public class AnalyzerTreeKeyboardTests
 		var typeNode = vm.AssemblyTreeModel.FindNode<TypeTreeNode>(
 			"System.Linq", "System.Linq", "System.Linq.Enumerable");
 		vm.AssemblyTreeModel.SelectNode(typeNode);
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			tree.UpdateLayout();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 		tree.Focus();
 		Dispatcher.UIThread.RunJobs();
 

ILSpy.Tests/AssemblyList/AssemblyTreeExpanderHitboxTests.cs

@@ -81,10 +81,7 @@ public class AssemblyTreeExpanderHitboxTests
 		// outside the centred glyph at ~y=3.5..12.5) collapses the node. This proves the grown
 		// area is genuinely hittable, not just larger in layout.
 		assemblyNode.IsExpanded.Should().BeTrue("precondition: node is expanded before the click");
-		var hitPoint = expander.TranslatePoint(new Point(expander.Bounds.Width / 2, 14), window);
-		hitPoint.Should().NotBeNull();
-		HeadlessWindowExtensions.MouseDown(window, hitPoint!.Value, MouseButton.Left);
-		HeadlessWindowExtensions.MouseUp(window, hitPoint.Value, MouseButton.Left);
+		await window.ClickAsync(() => expander, pointInTarget: e => new Point(e.Bounds.Width / 2, 14));
 		TestCapture.Step("clicked-enlarged-expander-area");
 
 		await Waiters.WaitForAsync(() => !assemblyNode.IsExpanded,

ILSpy.Tests/AssemblyList/AssemblyTreeTests.cs

@@ -634,11 +634,7 @@ public class AssemblyTreeTests
 
 		vm.AssemblyTreeModel.SelectNode(enumerable);
 		await Waiters.WaitForAsync(() => ReferenceEquals(vm.AssemblyTreeModel.SelectedItem, enumerable));
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 		grid.UpdateLayout();
 
 		var scrollViewer = await grid.WaitForComponent<ScrollViewer>();
@@ -665,19 +661,13 @@ public class AssemblyTreeTests
 		var offsetBefore = scrollViewer.Offset.Y;
 
 		// Act — real pointer click. Setting SelectedItem programmatically would fire DataGrid's
-		// internal ScrollIntoView too, which a real user click does not.
-		var rowCentre = candidateRow!.TranslatePoint(
-			new Point(candidateRow.Bounds.Width / 2, candidateRow.Bounds.Height / 2),
-			window)!.Value;
-		global::Avalonia.Headless.HeadlessWindowExtensions.MouseDown(window, rowCentre, global::Avalonia.Input.MouseButton.Left);
-		global::Avalonia.Headless.HeadlessWindowExtensions.MouseUp(window, rowCentre, global::Avalonia.Input.MouseButton.Left);
+		// internal ScrollIntoView too, which a real user click does not. Tree rows stretch to
+		// content width, so clamp X to the visible grid viewport.
+		await window.ClickAsync(() => candidateRow,
+			pointInTarget: r => new Point(System.Math.Min(r.Bounds.Width, grid.Bounds.Width) / 2, r.Bounds.Height / 2));
 		TestCapture.Step("visible-row-clicked");
 
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		// Assert — viewport offset is unchanged (within 1px tolerance for layout jitter).
 		scrollViewer.Offset.Y.Should().BeApproximately(offsetBefore, 1.0,
@@ -711,11 +701,7 @@ public class AssemblyTreeTests
 
 		vm.AssemblyTreeModel.SelectNode(enumerable);
 		await Waiters.WaitForAsync(() => ReferenceEquals(vm.AssemblyTreeModel.SelectedItem, enumerable));
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 		grid.UpdateLayout();
 
 		var scrollViewer = await grid.WaitForComponent<ScrollViewer>();
@@ -742,11 +728,7 @@ public class AssemblyTreeTests
 
 		// Act — model-driven selection (the open-in-new-tab path), NOT a mouse click.
 		vm.AssemblyTreeModel.SelectNode(candidateNode);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		scrollViewer.Offset.Y.Should().BeApproximately(offsetBefore, 1.0,
 			"selecting an already-visible row via the model (e.g. Decompile to new tab) must not move the viewport");
@@ -780,11 +762,7 @@ public class AssemblyTreeTests
 		// Select + reveal the type, then let it settle on screen.
 		vm.AssemblyTreeModel.SelectNode(enumerable);
 		await Waiters.WaitForAsync(() => ReferenceEquals(vm.AssemblyTreeModel.SelectedItem, enumerable));
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 		grid.UpdateLayout();
 
 		(scrollViewer.Extent.Height - scrollViewer.Viewport.Height).Should().BeGreaterThan(50,
@@ -795,11 +773,7 @@ public class AssemblyTreeTests
 		// rows above the selection and pushing it off-screen.
 		var coreLib = vm.AssemblyTreeModel.FindNode<AssemblyTreeNode>(typeof(object).Assembly.GetName().Name!);
 		coreLib.IsExpanded = true;
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 		grid.UpdateLayout();
 
 		// Assert: the app did not chase the selection. The expand reveals the opened node's children;
@@ -1774,14 +1748,9 @@ public class AssemblyTreeTests
 		Assert.That(targetNode, Is.Not.Null, "the clicked row must wrap a tree node");
 		// Tree rows stretch to content width (with horizontal scroll), so a row can be wider than
 		// the grid viewport. Click within the visible viewport, not at the (off-screen) row centre.
-		var clickX = System.Math.Min(targetRow.Bounds.Width, grid.Bounds.Width) / 2;
-		var rowCentre = targetRow.TranslatePoint(
-			new Point(clickX, targetRow.Bounds.Height / 2), window)!.Value;
-		HeadlessWindowExtensions.MouseDown(window, rowCentre, MouseButton.Left);
-		HeadlessWindowExtensions.MouseUp(window, rowCentre, MouseButton.Left);
-		Dispatcher.UIThread.RunJobs();
-		await Task.Delay(50);
-		Dispatcher.UIThread.RunJobs();
+		await window.ClickAsync(() => targetRow,
+			pointInTarget: r => new Point(System.Math.Min(r.Bounds.Width, grid.Bounds.Width) / 2, r.Bounds.Height / 2));
+		await Waiters.WaitForIdleAsync();
 		TestCapture.Step("plain-click-collapsed-selection");
 
 		// Assert — selection collapsed to exactly the clicked row, in both grid and model.
@@ -1822,11 +1791,7 @@ public class AssemblyTreeTests
 
 		// Act -- run Load Dependencies on the System.Net.Http node.
 		await vm.AssemblyTreeModel.LoadDependenciesAsync(new SharpTreeNode[] { httpNode });
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		// Assert -- references were resolved AND survive in the list as auto-loaded entries.
 		var added = vm.AssemblyTreeModel.AssemblyList!.GetAssemblies()

ILSpy.Tests/Bookmarks/BookmarkContextMenuTests.cs

@@ -54,11 +54,7 @@ public class BookmarkContextMenuTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		var bookmarkableLines = Enumerable.Range(1, view.Editor.Document.LineCount)
 			.Where(view.CanToggleBookmarkAtLine)
@@ -94,11 +90,7 @@ public class BookmarkContextMenuTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		int line = Enumerable.Range(1, view.Editor.Document.LineCount)
 			.First(view.CanToggleBookmarkAtLine);

ILSpy.Tests/Bookmarks/BookmarkGutterTests.cs

@@ -57,11 +57,7 @@ public class BookmarkGutterTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 		window.UpdateLayout();
 
 		var margin = view.Editor.TextArea.LeftMargins.OfType<BookmarkMargin>().Single();
@@ -107,11 +103,7 @@ public class BookmarkGutterTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 		window.UpdateLayout();
 
 		var margin = view.Editor.TextArea.LeftMargins.OfType<BookmarkMargin>().Single();
@@ -150,11 +142,7 @@ public class BookmarkGutterTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 		window.UpdateLayout();
 
 		var margin = view.Editor.TextArea.LeftMargins.OfType<BookmarkMargin>().Single();
@@ -231,11 +219,7 @@ public class BookmarkGutterTests
 			vm.AssemblyTreeModel.SelectNode(node);
 			await vm.DockWorkspace.WaitForDecompiledTextAsync();
 			var shown = await window.WaitForComponent<DecompilerTextView>();
-			for (int i = 0; i < 8; i++)
-			{
-				Dispatcher.UIThread.RunJobs();
-				await Task.Delay(25);
-			}
+			await Waiters.WaitForIdleAsync();
 			return shown;
 		}
 

ILSpy.Tests/Bookmarks/BookmarkNavigationViewTests.cs

@@ -59,11 +59,7 @@ public class BookmarkNavigationViewTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		int bookmarkLine = Enumerable.Range(1, view.Editor.Document.LineCount)
 			.Where(view.CanToggleBookmarkAtLine)
@@ -232,10 +228,6 @@ public class BookmarkNavigationViewTests
 
 	static async Task PumpLayoutAsync()
 	{
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 	}
 }

ILSpy.Tests/ContextMenus/DecompileInNewViewTests.cs

@@ -181,12 +181,7 @@ public class DecompileInNewViewTests
 		vm.AssemblyTreeModel.SelectNode(nodeA);
 
 		// Let the top-level rows realise and layout settle.
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		var rowB = grid.GetVisualDescendants().OfType<ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem>()
 			.FirstOrDefault(r => RowNodeEquals(r, nodeB));
@@ -200,16 +195,9 @@ public class DecompileInNewViewTests
 
 		// Right-click the centre of B's row (clear of the far-left expander glyph). Tree rows
 		// stretch to content width, so clamp X to the visible grid viewport.
-		var clickX = System.Math.Min(rowB!.Bounds.Width, grid.Bounds.Width) / 2;
-		var point = rowB.TranslatePoint(new Point(clickX, rowB.Bounds.Height / 2), window);
-		point.Should().NotBeNull();
-		HeadlessWindowExtensions.MouseDown(window, point!.Value, MouseButton.Right);
-		HeadlessWindowExtensions.MouseUp(window, point.Value, MouseButton.Right);
-		for (int i = 0; i < 4; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await window.ClickAsync(() => rowB, MouseButton.Right,
+			pointInTarget: r => new Point(System.Math.Min(r.Bounds.Width, grid.Bounds.Width) / 2, r.Bounds.Height / 2));
+		await Waiters.WaitForIdleAsync();
 
 		ReferenceEquals(vm.AssemblyTreeModel.SelectedItem, nodeA).Should().BeTrue(
 			"right-clicking an unselected row must not change the selection (Thunderbird-style context target)");
@@ -239,12 +227,7 @@ public class DecompileInNewViewTests
 		var nodeC = assemblies[2];
 
 		vm.AssemblyTreeModel.SelectNode(nodeA);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem Row(SharpTreeNode node) => grid.GetVisualDescendants()
 			.OfType<ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem>()
@@ -252,43 +235,16 @@ public class DecompileInNewViewTests
 
 		var menu = grid.ContextMenu!;
 
-		Point? ClickPoint(SharpTreeNode node)
-		{
-			var row = grid.GetVisualDescendants()
-				.OfType<ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem>()
-				.FirstOrDefault(r => RowNodeEquals(r, node));
-			if (row == null)
-				return null;
-			var clickX = System.Math.Min(row.Bounds.Width, grid.Bounds.Width) / 2;
-			return row.TranslatePoint(new Point(clickX, row.Bounds.Height / 2), window);
-		}
-
 		async Task RightClick(SharpTreeNode node)
 		{
-			// A press only becomes a context request for the row when the hit test at the press
-			// point answers with that row - the same question OnTreeContextRequested asks - and it
-			// takes an unknown number of frames for that to hold: a closed popup's light-dismiss
-			// overlay keeps answering hit tests until the scene is rendered again, and assemblies
-			// still loading in the background reshuffle the rows, which re-realises containers and
-			// shifts them. So the row container and the point are resolved afresh on every poll and
-			// the hit is matched by node, not by container identity.
-			Point? pt = null;
-			Visual? lastHit = null;
-			try
-			{
-				await Waiters.WaitForAsync(
-					() => (pt = ClickPoint(node)) is { } p
-						&& (lastHit = window.InputHitTest(p) as Visual) is { } hit
-						&& hit.FindAncestorOfType<ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem>(includeSelf: true) is { } hitRow
-						&& RowNodeEquals(hitRow, node),
-					description: "the row to answer hit tests at the point about to be right-clicked");
-			}
-			catch (System.TimeoutException ex)
-			{
-				throw new System.TimeoutException($"{ex.Message} (point: {pt?.ToString() ?? "row not realised"}, hit: {lastHit?.GetType().Name ?? "nothing"})", ex);
-			}
-			HeadlessWindowExtensions.MouseDown(window, pt!.Value, MouseButton.Right);
-			HeadlessWindowExtensions.MouseUp(window, pt.Value, MouseButton.Right);
+			// Tree rows stretch to content width, so clamp X to the visible grid viewport.
+			await window.ClickAsync(
+				() => grid.GetVisualDescendants()
+					.OfType<ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem>()
+					.FirstOrDefault(r => RowNodeEquals(r, node)),
+				MouseButton.Right,
+				pointInTarget: row => new Point(System.Math.Min(row.Bounds.Width, grid.Bounds.Width) / 2, row.Bounds.Height / 2),
+				description: $"the row for {node}");
 			// The highlight is scoped to the popup - set while the menu is being requested, dropped
 			// again when it closes - so the popup is the point at which the gesture is finished and
 			// the row's classes are worth reading.
@@ -328,27 +284,15 @@ public class DecompileInNewViewTests
 		var nodeA = vm.AssemblyTreeModel.FindNode<AssemblyTreeNode>("System.Linq");
 		var nodeB = vm.AssemblyTreeModel.FindNode<AssemblyTreeNode>(TreeNavigation.CoreLibName);
 		vm.AssemblyTreeModel.SelectNode(nodeA);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		var rowB = grid.GetVisualDescendants().OfType<ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem>()
 			.First(r => RowNodeEquals(r, nodeB));
 		int tabsBefore = vm.DockWorkspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count();
 
-		var clickX = System.Math.Min(rowB.Bounds.Width, grid.Bounds.Width) / 2;
-		var point = rowB.TranslatePoint(new Point(clickX, rowB.Bounds.Height / 2), window)!.Value;
-		HeadlessWindowExtensions.MouseDown(window, point, MouseButton.Middle);
-		HeadlessWindowExtensions.MouseUp(window, point, MouseButton.Middle);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(20);
-		}
+		await window.ClickAsync(() => rowB, MouseButton.Middle,
+			pointInTarget: r => new Point(System.Math.Min(r.Bounds.Width, grid.Bounds.Width) / 2, r.Bounds.Height / 2));
+		await Waiters.WaitForIdleAsync();
 
 		vm.DockWorkspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count()
 			.Should().BeGreaterThan(tabsBefore, "middle-clicking a row must open it in a new document tab");
@@ -376,23 +320,13 @@ public class DecompileInNewViewTests
 
 		vm.AssemblyTreeModel.SelectNode(nodeA);
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		var registry = AppComposition.Current.GetExport<ContextMenuEntryRegistry>();
 		var menu = pane.BuildContextMenuForCurrentState(registry.Entries, rightClickedNode: nodeB);
 		menu!.ClickItem(Resources.DecompileToNewPanel);
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		// The model selection follows the new active tab...
 		ReferenceEquals(vm.AssemblyTreeModel.SelectedItem, nodeB).Should().BeTrue(
@@ -428,12 +362,7 @@ public class DecompileInNewViewTests
 		vm.AssemblyTreeModel.SelectedItems.Add(nodeA);
 		vm.AssemblyTreeModel.SelectedItems.Add(nodeB);
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 		vm.AssemblyTreeModel.SelectedItems.Count.Should().Be(2, "precondition: a multi-selection is held");
 
 		// Open C in a new tab -> activates it -> the tree must follow to C.
@@ -441,12 +370,7 @@ public class DecompileInNewViewTests
 		var menu = pane.BuildContextMenuForCurrentState(registry.Entries, rightClickedNode: nodeC);
 		menu!.ClickItem(Resources.DecompileToNewPanel);
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		ReferenceEquals(vm.AssemblyTreeModel.SelectedItem, nodeC).Should().BeTrue(
 			"the tree model selection must follow the newly-activated single-node tab");
@@ -494,12 +418,7 @@ public class DecompileInNewViewTests
 
 		// 3) Re-activate the multi-node tab.
 		vm.DockWorkspace.Factory.SetActiveDockable(multiTab);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		// 4) The tree selection must contain BOTH original nodes again -- in the model...
 		vm.AssemblyTreeModel.SelectedItems.Should().Contain(nodeA)

ILSpy.Tests/ContextMenus/KeyboardContextMenuFocusTests.cs

@@ -60,12 +60,7 @@ public class KeyboardContextMenuFocusTests
 
 		var node = vm.AssemblyTreeModel.Root!.Children.OfType<AssemblyTreeNode>().First();
 		vm.AssemblyTreeModel.SelectNode(node);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			grid.UpdateLayout();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		var row = grid.GetVisualDescendants()
 			.OfType<ICSharpCode.ILSpy.Controls.TreeView.SharpTreeViewItem>().First();
@@ -77,21 +72,13 @@ public class KeyboardContextMenuFocusTests
 
 		// Keyboard invocation raises ContextRequested with no pointer position (the Shift+F10 / Apps path).
 		row.RaiseEvent(new ContextRequestedEventArgs());
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 		grid.ContextMenu!.IsOpen.Should().BeTrue("the keyboard gesture must open the tree context menu");
 		row.Classes.Should().Contain("contextTarget",
 			"a keyboard-invoked menu must show the transient target highlight on the selected row, like the mouse path");
 
 		window.KeyPress(Key.Escape, RawInputModifiers.None, PhysicalKey.Escape, keySymbol: null);
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		(focusManager.GetFocusedElement() == row).Should().BeTrue(
 			"closing a keyboard-invoked context menu must return focus to the row, not strand it");

ILSpy.Tests/ContextMenus/ReferenceScopeAndNewTabTests.cs

@@ -64,11 +64,7 @@ public class ReferenceScopeAndNewTabTests
 
 		int before = vm.DockWorkspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count();
 		entry.Execute(RefContext(entity));
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		vm.DockWorkspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count()
 			.Should().BeGreaterThan(before, "Decompile to new tab on a code reference must open a new document tab");

ILSpy.Tests/Controls/OmnibarSettingTests.cs

@@ -51,17 +51,11 @@ public class OmnibarSettingTests
 			"System.Linq", "System.Linq", "System.Linq.Enumerable");
 		vm.AssemblyTreeModel.SelectedItem = typeNode;
 		Omnibar? omnibar = null;
-		for (int i = 0; i < 200; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			omnibar = window.GetVisualDescendants().OfType<DecompilerTextView>()
+		await Waiters.WaitForAsync(() => (omnibar = window.GetVisualDescendants().OfType<DecompilerTextView>()
 				.Where(v => v.IsEffectivelyVisible)
 				.SelectMany(v => v.GetVisualDescendants().OfType<Omnibar>())
-				.FirstOrDefault();
-			if (omnibar != null)
-				break;
-			await Task.Delay(20);
-		}
+				.FirstOrDefault()) != null,
+			description: "a visible decompiler text view hosting the omnibar");
 		Assert.That(omnibar, Is.Not.Null, "selecting a node realizes a decompiler text view hosting the omnibar");
 
 		Assert.That(omnibar!.IsVisible, Is.False,

ILSpy.Tests/Docking/DocumentTabStripModeTests.cs

@@ -65,15 +65,7 @@ public class DocumentTabStripModeTests
 		return (window, strip);
 	}
 
-	static async Task Pump(MainWindow window)
-	{
-		for (int i = 0; i < 12; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			window.UpdateLayout();
-			await Task.Delay(20);
-		}
-	}
+	static Task Pump(MainWindow window) => Waiters.WaitForIdleAsync();
 
 	static Button? Dropdown(DocumentTabStrip strip)
 		=> strip.GetVisualDescendants().OfType<Button>()
@@ -175,10 +167,7 @@ public class DocumentTabStripModeTests
 
 			// Drive a real pointer click through the input pipeline (open is deferred a dispatcher
 			// turn, which Pump runs), so this would have caught the menu failing to open on a live click.
-			var centre = button.TranslatePoint(new Point(button.Bounds.Width / 2, button.Bounds.Height / 2), window)
-				?? new Point(8, 8);
-			window.MouseDown(centre, MouseButton.Left);
-			window.MouseUp(centre, MouseButton.Left);
+			await window.ClickAsync(() => button);
 			await Pump(window);
 
 			opened.Should().BeTrue("clicking the dropdown must open its menu");
@@ -198,10 +187,7 @@ public class DocumentTabStripModeTests
 			var button = Dropdown(strip);
 			var menu = button!.ContextMenu!;
 
-			var centre = button.TranslatePoint(new Point(button.Bounds.Width / 2, button.Bounds.Height / 2), window)
-				?? new Point(8, 8);
-			window.MouseDown(centre, MouseButton.Left);
-			window.MouseUp(centre, MouseButton.Left);
+			await window.ClickAsync(() => button);
 			await Pump(window);
 
 			var target = strip.Items.OfType<ContentTabPage>().Last();

ILSpy.Tests/Docking/MultiRowTabStripTests.cs

@@ -61,12 +61,7 @@ public class MultiRowTabStripTests
 			for (int i = 0; i < 40; i++)
 				vm.DockWorkspace.OpenNewTab(new DecompilerTabPageModel { Title = $"Tab number {i:00}" });
 
-			for (int i = 0; i < 12; i++)
-			{
-				Dispatcher.UIThread.RunJobs();
-				window.UpdateLayout();
-				await Task.Delay(20);
-			}
+			await Waiters.WaitForIdleAsync();
 
 			var strip = window.GetVisualDescendants().OfType<DocumentTabStrip>().FirstOrDefault();
 			strip.Should().NotBeNull("the document tab strip must be realised");

ILSpy.Tests/Docking/RunInNewTabTests.cs

@@ -77,11 +77,7 @@ public class RunInNewTabTests
 			TreeNavigation.CoreLibName, "System.Runtime.Versioning");
 		vm.AssemblyTreeModel.SelectNode(navNode);
 		await dock.WaitForDecompiledTextAsync();
-		for (int i = 0; i < 6; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		capturedToken.IsCancellationRequested.Should().BeFalse(
 			"navigating the tree must NOT cancel a long op running in its own frozen tab");

ILSpy.Tests/Editor/DecompilerViewTests.cs

@@ -460,11 +460,7 @@ public class DecompilerViewTests
 		await Waiters.WaitForAsync(() => tab.SyntaxExtension == ".xml" && tab.Text.Contains("<root>"));
 
 		// Drain the layout so ApplyDocument's PropertyChanged handler has executed.
-		for (int i = 0; i < 5; i++)
-		{
-			global::Avalonia.Threading.Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 		host.Capture("xml-folding");
 
 		// Assert — FoldingManager is installed (private field, reflected) and produced fold

ILSpy.Tests/Editor/DocumentationLinkTests.cs

@@ -92,10 +92,7 @@ public class DocumentationLinkTests
 		MessageBus<NavigateToReferenceEventArgs>.Subscribers += capture;
 		try
 		{
-			var centre = link.TranslatePoint(
-				new Point(link.Bounds.Width / 2, link.Bounds.Height / 2), window)!.Value;
-			window.MouseDown(centre, MouseButton.Left);
-			window.MouseUp(centre, MouseButton.Left);
+			await window.ClickAsync(() => link);
 		}
 		finally
 		{

ILSpy.Tests/Editor/FoldingContextMenuTests.cs

@@ -54,11 +54,7 @@ public class FoldingContextMenuTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		view.HasFoldings.Should().BeTrue("decompiling a type produces brace foldings");
 
@@ -100,11 +96,7 @@ public class FoldingContextMenuTests
 		await vm.DockWorkspace.WaitForDecompiledTextAsync();
 
 		var view = await window.WaitForComponent<DecompilerTextView>();
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(25);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		// ILSpy collapses method-body folds by default, leaving the outer type-body fold open. Two of
 		// those collapsed method folds are disjoint siblings: right-click "Toggle folding" on one while

ILSpy.Tests/Metadata/MetadataFilterRowEndToEndTests.cs

@@ -17,6 +17,7 @@
 // DEALINGS IN THE SOFTWARE.
 
 using System.Linq;
+using System.Threading.Tasks;
 using System.Reflection;
 
 using Avalonia;
@@ -73,7 +74,7 @@ public class MetadataFilterRowEndToEndTests
 		});
 
 	[AvaloniaTest]
-	public void Clicking_Inside_The_Popup_Never_Sorts_The_Column_Of_A_Real_DataGrid()
+	public async Task Clicking_Inside_The_Popup_Never_Sorts_The_Column_Of_A_Real_DataGrid()
 	{
 		// Full assembly of the real parts: an actual DataGrid with CanUserSortColumns
 		// (as MetadataTablePage.axaml configures it), the builder's columns, the overlay
@@ -116,9 +117,7 @@ public class MetadataFilterRowEndToEndTests
 		// "Filter Attributes" tooltip).
 		var funnel = FindAttributesFunnel(headerPanel);
 		var flyout = (Flyout)FlyoutBase.GetAttachedFlyout(funnel)!;
-		var funnelCenter = funnel.TranslatePoint(new Point(funnel.Bounds.Width / 2, funnel.Bounds.Height / 2), window)!.Value;
-		window.MouseDown(funnelCenter, MouseButton.Left);
-		window.MouseUp(funnelCenter, MouseButton.Left);
+		await window.ClickAsync(() => funnel);
 		flyout.IsOpen.Should().BeTrue("setup precondition — the funnel click must open the flyout");
 		window.UpdateLayout();
 		Dispatcher.UIThread.RunJobs();

ILSpy.Tests/Options/OptionsTabTests.cs

@@ -331,8 +331,7 @@ public class OptionsTabTests
 		// Toggle a re-decompile display setting.
 		var display = AppComposition.Current.GetExport<SettingsService>().DisplaySettings;
 		display.DecodeCustomAttributeBlobs = !display.DecodeCustomAttributeBlobs;
-		for (int i = 0; i < 12; i++)
-			Dispatcher.UIThread.RunJobs();
+		await Waiters.WaitForIdleAsync();
 
 		documents.ActiveDockable.Should().BeSameAs(optionsTab,
 			"an output display setting must re-decompile in place, not switch the user off the focused tab");

ILSpy.Tests/Search/SearchPaneNicetiesTests.cs

@@ -156,11 +156,7 @@ public class SearchPaneNicetiesTests
 		int before = workspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count();
 
 		RaiseKey(results, Key.Enter, KeyModifiers.Control);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		workspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count()
 			.Should().BeGreaterThan(before, "Ctrl+Enter on a result opens it in a new document tab instead of reusing the active one");
@@ -183,11 +179,7 @@ public class SearchPaneNicetiesTests
 		int before = workspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count();
 
 		vm.Activate(hit, inNewTabPage: true);
-		for (int i = 0; i < 8; i++)
-		{
-			Dispatcher.UIThread.RunJobs();
-			await Task.Delay(20);
-		}
+		await Waiters.WaitForIdleAsync();
 
 		workspace.Documents!.VisibleDockables!.OfType<ContentTabPage>().Count()
 			.Should().BeGreaterThan(before, "Activate(inNewTabPage: true) must route through OpenNodeInNewTab");

ILSpy.Tests/Waiters.cs

@@ -26,6 +26,7 @@ using Avalonia.Headless;
 using Avalonia.Threading;
 using Avalonia.VisualTree;
 
+using ICSharpCode.ILSpy.AppEnv;
 using ICSharpCode.ILSpy.AssemblyTree;
 using ICSharpCode.ILSpy.Docking;
 using ICSharpCode.ILSpy.TextView;
@@ -75,6 +76,42 @@ public static class Waiters
 		AvaloniaHeadlessPlatform.ForceRenderTimerTick();
 	}
 
+	/// <summary>
+	/// Waits until the application has nothing left to do: no dispatcher job queued at Background
+	/// priority or above, no assembly still loading in the background sweep, layout up to date and
+	/// a frame rendered - and until that holds on two consecutive polls, so work that a
+	/// thread-pool continuation is about to post back to the UI thread is caught as well.
+	/// </summary>
+	/// <remarks>
+	/// This is the synchronization point to use between an action and the assertions or input
+	/// that follow it. Pumping a fixed number of frames instead encodes how fast the machine that
+	/// wrote the test was, and comes apart on a loaded CI agent; "nothing pending" is the actual
+	/// precondition, whatever number of frames it takes.
+	/// </remarks>
+	public static async Task WaitForIdleAsync(TimeSpan? timeout = null)
+	{
+		var deadline = DateTime.UtcNow + (timeout ?? DefaultTimeout);
+		int consecutiveIdlePolls = 0;
+		while (DateTime.UtcNow < deadline)
+		{
+			PumpUI();
+			consecutiveIdlePolls = IsIdle() ? consecutiveIdlePolls + 1 : 0;
+			if (consecutiveIdlePolls >= 2)
+				return;
+			await Task.Delay(PollInterval);
+		}
+		throw new TimeoutException(
+			$"Timed out after {(timeout ?? DefaultTimeout).TotalSeconds:0.#}s waiting for the UI to become idle");
+
+		static bool IsIdle()
+		{
+			if (Dispatcher.UIThread.HasJobsWithPriority(DispatcherPriority.Background))
+				return false;
+			var assemblies = AppComposition.TryGetExport<AssemblyTreeModel>()?.AssemblyList?.GetAssemblies();
+			return assemblies == null || Array.TrueForAll(assemblies, a => a.IsLoaded);
+		}
+	}
+
 	public static async Task WaitForAssembliesAsync(
 		this AssemblyTreeModel atm,
 		int minimumCount = 1,

ILSpy.Tests/WindowExtensions.cs

@@ -21,16 +21,69 @@ using System.Diagnostics;
 using System.IO;
 using System.Linq;
 using System.Runtime.CompilerServices;
+using System.Threading.Tasks;
 
+using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Headless;
+using Avalonia.Input;
 using Avalonia.Media.Imaging;
 using Avalonia.Threading;
+using Avalonia.VisualTree;
 
 namespace ICSharpCode.ILSpy.Tests;
 
 public static class WindowExtensions
 {
+	/// <summary>
+	/// Presses and releases <paramref name="button"/> on the visual <paramref name="resolveTarget"/>
+	/// returns, once the window's hit test at the click point answers with that visual (or a
+	/// descendant of it). Returns the window-relative point that was clicked.
+	/// </summary>
+	/// <remarks>
+	/// Synthesized input is routed by hit testing the rendered scene, so a press only reaches the
+	/// intended control when the scene agrees with the visual tree: a closed popup's light-dismiss
+	/// overlay keeps answering hit tests until the next frame, a virtualized row may be re-realised
+	/// as a different container, and layout may still be moving. Resolving the target on every poll
+	/// and waiting for the hit test is that precondition, whatever number of frames it takes.
+	/// <paramref name="pointInTarget"/> picks the point inside the target's bounds; the centre by
+	/// default.
+	/// </remarks>
+	public static async Task<Point> ClickAsync(
+		this Window window,
+		Func<Visual?> resolveTarget,
+		MouseButton button = MouseButton.Left,
+		RawInputModifiers modifiers = RawInputModifiers.None,
+		Func<Visual, Point>? pointInTarget = null,
+		[CallerArgumentExpression(nameof(resolveTarget))] string? description = null)
+	{
+		ArgumentNullException.ThrowIfNull(window);
+		ArgumentNullException.ThrowIfNull(resolveTarget);
+		pointInTarget ??= static t => new Point(t.Bounds.Width / 2, t.Bounds.Height / 2);
+		Visual? target = null;
+		Point? point = null;
+		object? lastHit = null;
+		try
+		{
+			await Waiters.WaitForAsync(() => {
+				target = resolveTarget();
+				point = target == null ? null : target.TranslatePoint(pointInTarget(target), window);
+				if (point == null)
+					return false;
+				lastHit = window.InputHitTest(point.Value);
+				return lastHit is Visual hit && (ReferenceEquals(hit, target) || hit.GetVisualAncestors().Contains(target));
+			}, description: $"{description} to answer the hit test at its click point");
+		}
+		catch (TimeoutException ex)
+		{
+			throw new TimeoutException(
+				$"{ex.Message} (target: {target?.GetType().Name ?? "not resolved"}, point: {point?.ToString() ?? "n/a"}, hit: {lastHit?.GetType().Name ?? "nothing"})", ex);
+		}
+		window.MouseDown(point!.Value, button, modifiers);
+		window.MouseUp(point.Value, button, modifiers);
+		return point.Value;
+	}
+
 	/// <summary>Snapshots the window with Skia, writes a temp PNG, and opens it in the OS
 	/// image viewer. No-op when <c>UseHeadlessDrawing</c> is true (CI default).</summary>
 	public static void CaptureAndShow(this Window window, [CallerMemberName] string? label = null)