Fix flakiness and edge cases in integration tests

Author: sharwell

Tvl.VisualStudio.MouseFastScroll.IntegrationTests/Editor_InProc.cs

@@ -8,6 +8,7 @@ namespace Tvl.VisualStudio.MouseFastScroll.IntegrationTests
     using System.Windows;
     using Microsoft.VisualStudio.Text;
     using Microsoft.VisualStudio.Text.Editor;
+    using Microsoft.VisualStudio.Text.Formatting;
     using Microsoft.VisualStudio.TextManager.Interop;
 
     internal class Editor_InProc : TextViewWindow_InProc
@@ -105,6 +106,11 @@ public int GetLastVisibleLine()
             return ExecuteOnActiveView(view => view.TextViewLines.LastVisibleLine.Start.GetContainingLine().LineNumber);
         }
 
+        public int GetLastVisibleLineState()
+        {
+            return ExecuteOnActiveView(view => (int)view.TextViewLines.LastVisibleLine.VisibilityState);
+        }
+
         public Point GetCenterOfEditorOnScreen()
         {
             return ExecuteOnActiveView(

Tvl.VisualStudio.MouseFastScroll.IntegrationTests/Editor_OutOfProc.cs

@@ -4,6 +4,7 @@
 namespace Tvl.VisualStudio.MouseFastScroll.IntegrationTests
 {
     using System.Windows;
+    using Microsoft.VisualStudio.Text.Formatting;
     using WindowsInput.Native;
 
     public class Editor_OutOfProc : TextViewWindow_OutOfProc
@@ -54,6 +55,9 @@ public int GetFirstVisibleLine()
         public int GetLastVisibleLine()
             => EditorInProc.GetLastVisibleLine();
 
+        public VisibilityState GetLastVisibleLineState()
+            => (VisibilityState)EditorInProc.GetLastVisibleLineState();
+
         public Point GetCenterOfEditorOnScreen()
             => EditorInProc.GetCenterOfEditorOnScreen();
 

Tvl.VisualStudio.MouseFastScroll.IntegrationTests/TrivialIntegrationTest.cs

@@ -7,6 +7,7 @@ namespace Tvl.VisualStudio.MouseFastScroll.IntegrationTests
     using System.Linq;
     using System.Windows;
     using System.Windows.Media;
+    using Microsoft.VisualStudio.Text.Formatting;
     using WindowsInput;
     using WindowsInput.Native;
     using Xunit;
@@ -70,6 +71,7 @@ public void BasicScrollingBehavior()
             Assert.Equal(0, firstVisibleLine);
 
             int lastVisibleLine = VisualStudio.Editor.GetLastVisibleLine();
+            VisibilityState lastVisibleLineState = VisualStudio.Editor.GetLastVisibleLineState();
             Assert.True(firstVisibleLine < lastVisibleLine);
 
             Point point = VisualStudio.Editor.GetCenterOfEditorOnScreen();
@@ -81,30 +83,39 @@ public void BasicScrollingBehavior()
                 .MoveMouseTo(point.X, point.Y)
                 .VerticalScroll(-1);
 
+            VisualStudio.WaitForApplicationIdle();
+
             Assert.Equal(0, VisualStudio.Editor.GetCaretPosition());
             Assert.Equal(3, VisualStudio.Editor.GetFirstVisibleLine());
 
             inputSimulator.Mouse
                 .MoveMouseTo(point.X, point.Y)
                 .VerticalScroll(1);
 
+            VisualStudio.WaitForApplicationIdle();
+
             Assert.Equal(0, VisualStudio.Editor.GetCaretPosition());
             Assert.Equal(0, VisualStudio.Editor.GetFirstVisibleLine());
 
             inputSimulator
                 .Mouse.MoveMouseTo(point.X, point.Y)
                 .Keyboard.KeyDown(VirtualKeyCode.CONTROL)
                 .Mouse.VerticalScroll(-1)
-                .Keyboard.KeyUp(VirtualKeyCode.CONTROL);
+                .Keyboard.Sleep(10).KeyUp(VirtualKeyCode.CONTROL);
 
+            VisualStudio.WaitForApplicationIdle();
+
+            int expectedLastVisibleLine = lastVisibleLine + (lastVisibleLineState == VisibilityState.FullyVisible ? 1 : 0);
             Assert.Equal(0, VisualStudio.Editor.GetCaretPosition());
-            Assert.Equal(lastVisibleLine, VisualStudio.Editor.GetFirstVisibleLine());
+            Assert.Equal(expectedLastVisibleLine, VisualStudio.Editor.GetFirstVisibleLine());
 
             inputSimulator
                 .Mouse.MoveMouseTo(point.X, point.Y)
                 .Keyboard.KeyDown(VirtualKeyCode.CONTROL)
                 .Mouse.VerticalScroll(1)
-                .Keyboard.KeyUp(VirtualKeyCode.CONTROL);
+                .Keyboard.Sleep(10).KeyUp(VirtualKeyCode.CONTROL);
+
+            VisualStudio.WaitForApplicationIdle();
 
             Assert.Equal(0, VisualStudio.Editor.GetCaretPosition());
             Assert.Equal(0, VisualStudio.Editor.GetFirstVisibleLine());
@@ -144,6 +155,7 @@ public void ZoomDisabled()
             Assert.Equal(0, firstVisibleLine);
 
             int lastVisibleLine = VisualStudio.Editor.GetLastVisibleLine();
+            VisibilityState lastVisibleLineState = VisualStudio.Editor.GetLastVisibleLineState();
             Assert.True(firstVisibleLine < lastVisibleLine);
 
             double zoomLevel = VisualStudio.Editor.GetZoomLevel();
@@ -157,19 +169,20 @@ public void ZoomDisabled()
                 .Mouse.MoveMouseTo(point.X, point.Y)
                 .Keyboard.KeyDown(VirtualKeyCode.CONTROL)
                 .Mouse.VerticalScroll(-1)
-                .Keyboard.KeyUp(VirtualKeyCode.CONTROL);
+                .Keyboard.Sleep(10).KeyUp(VirtualKeyCode.CONTROL);
 
             VisualStudio.WaitForApplicationIdle();
 
+            int expectedLastVisibleLine = lastVisibleLine + (lastVisibleLineState == VisibilityState.FullyVisible ? 1 : 0);
             Assert.Equal(0, VisualStudio.Editor.GetCaretPosition());
-            Assert.Equal(lastVisibleLine, VisualStudio.Editor.GetFirstVisibleLine());
+            Assert.Equal(expectedLastVisibleLine, VisualStudio.Editor.GetFirstVisibleLine());
             Assert.Equal(zoomLevel, VisualStudio.Editor.GetZoomLevel());
 
             inputSimulator
                 .Mouse.MoveMouseTo(point.X, point.Y)
                 .Keyboard.KeyDown(VirtualKeyCode.CONTROL)
                 .Mouse.VerticalScroll(1)
-                .Keyboard.KeyUp(VirtualKeyCode.CONTROL);
+                .Keyboard.Sleep(10).KeyUp(VirtualKeyCode.CONTROL);
 
             VisualStudio.WaitForApplicationIdle();