Add workaround for ugly rainbow tooltips in VS2017 15.6 (issue #233)

src/Viasfora.Core/Contracts/IVsFeatures.cs

@@ -0,0 +1,7 @@
+using System;
+
+namespace Winterdom.Viasfora.Contracts {
+  public interface IVsFeatures {
+    bool IsSupported(String featureName);
+  }
+}

src/Viasfora.Core/KnownFeatures.cs

@@ -0,0 +1,7 @@
+using System;
+
+namespace Winterdom.Viasfora {
+  public static class KnownFeatures {
+    public const String TooltipApi = nameof(TooltipApi);
+  }
+}

src/Viasfora.Core/Util/VsFeatures.cs

@@ -0,0 +1,23 @@
+using Microsoft.VisualStudio.Language.Intellisense;
+using System;
+using System.ComponentModel.Composition;
+using Winterdom.Viasfora.Contracts;
+
+namespace Winterdom.Viasfora.Util {
+  [Export(typeof(IVsFeatures))]
+  public class VsFeatures : IVsFeatures {
+    public bool IsSupported(string featureName) {
+      switch ( featureName ) {
+        case KnownFeatures.TooltipApi:
+          return IsQuickInfoSourceDeprecated();
+      }
+      throw new InvalidOperationException("Unknown feature: " + featureName);
+    }
+
+    private bool IsQuickInfoSourceDeprecated() {
+      return typeof(IQuickInfoSource)
+            .GetCustomAttributes(typeof(ObsoleteAttribute), false)
+            .Length > 0;
+    }
+  }
+}

src/Viasfora.Core/Viasfora.Core.csproj

@@ -158,6 +158,7 @@
     <Compile Include="Contracts\ILogger.cs" />
     <Compile Include="Contracts\IPackageUserOptions.cs" />
     <Compile Include="Contracts\IPresentationModeState.cs" />
+    <Compile Include="Contracts\IVsFeatures.cs" />
     <Compile Include="Contracts\IVsfTelemetry.cs" />
     <Compile Include="DefaultNames.cs" />
     <Compile Include="Design\NativeMethods.cs" />
@@ -182,6 +183,7 @@
     <Compile Include="IUpdatableSettings.cs" />
     <Compile Include="IVsfSettings.cs" />
     <Compile Include="JsonExtensions.cs" />
+    <Compile Include="KnownFeatures.cs" />
     <Compile Include="LanguageExtensions.cs" />
     <Compile Include="Margins\DevMarginProvider.cs" />
     <Compile Include="Margins\DevMarginViewModel.cs" />
@@ -263,6 +265,7 @@
     <Compile Include="Util\StringChars.cs" />
     <Compile Include="Util\StringPart.cs" />
     <Compile Include="Util\VsColors.cs" />
+    <Compile Include="Util\VsFeatures.cs" />
     <Compile Include="VsSolution.cs" />
     <Compile Include="XLangSupport\FakeContentTypeDefinition.cs" />
     <Compile Include="XLangSupport\XLangTextViewCreationListener.cs" />

src/Viasfora.Rainbow/Util/ToolTipWindow.cs

@@ -2,10 +2,12 @@
 using System.ComponentModel.Composition;
 using System.Windows;
 using System.Windows.Controls;
+using System.Windows.Media;
 using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Text.Editor;
 using Microsoft.VisualStudio.Text.Formatting;
 using Microsoft.VisualStudio.Utilities;
+using Winterdom.Viasfora.Contracts;
 using Winterdom.Viasfora.Rainbow;
 
 namespace Winterdom.Viasfora.Util {
@@ -15,6 +17,8 @@ public class ToolTipWindowProvider : IToolTipWindowProvider {
     public ITextEditorFactoryService EditorFactory { get; set; }
     [Import]
     public IEditorOptionsFactoryService OptionsFactory { get; set; }
+    [Import]
+    public IVsFeatures VsFeatures { get; set; }
 
     public IToolTipWindow CreateToolTip(ITextView textView) {
       return new ToolTipWindow(textView, this);
@@ -139,6 +143,13 @@ private void CreateTipView() {
       options.SetOptionValue(ViewOptions.WordWrapStyleId, WordWrapStyles.None);
       options.SetOptionValue(ViewOptions.ViewProhibitUserInput, true);
 
+      // only for VS2017 15.6 and up, where IIntellisensePresenter is
+      // not supported anymore (replaced by the tooltip APIs), we
+      // set the background to transparent so that it looks like regular
+      // intellisense popup
+      if ( this.provider.VsFeatures.IsSupported(KnownFeatures.TooltipApi) ) {
+        this.tipView.Background = Brushes.Transparent;
+      }
       this.tipView.ViewportWidthChanged += OnViewportWidthChanged;
 
       this.tipView.ZoomLevel = GetSourceZoomFactor() * ZoomFactor * 100;