VS: make Alt-F1 work for inline hints

docs/release-notes/.VisualStudio/18.vNext.md

@@ -4,6 +4,7 @@
 * Fixed Find All References crash when F# project contains non-F# files like `.cshtml`. ([Issue #16394](https://github.com/dotnet/fsharp/issues/16394), [PR #19252](https://github.com/dotnet/fsharp/pull/19252))
 * Find All References for external DLL symbols now only searches projects that reference the specific assembly. ([Issue #10227](https://github.com/dotnet/fsharp/issues/10227), [PR #19252](https://github.com/dotnet/fsharp/pull/19252))
 * Improve static compilation of state machines. ([PR #19297](https://github.com/dotnet/fsharp/pull/19297))
+* Make Alt+F1 (momentary toggle) work for inlay hints. ([PR #19421](https://github.com/dotnet/fsharp/pull/19421))
 
 ### Changed
 

vsintegration/src/FSharp.Editor/Hints/FSharpInlayHintsService.fs

@@ -4,25 +4,28 @@ namespace Microsoft.VisualStudio.FSharp.Editor.Hints
 
 open System.Collections.Immutable
 open System.ComponentModel.Composition
+open System.Threading.Tasks
 open Microsoft.CodeAnalysis.ExternalAccess.FSharp.InlineHints
 open Microsoft.VisualStudio.FSharp.Editor
-open Microsoft.VisualStudio.FSharp.Editor.Telemetry
 open CancellableTasks
-open System.Threading.Tasks
 
 // So the Roslyn interface is called IFSharpInlineHintsService
 // but our implementation is called just HintsService.
 // That's because we'll likely use this API for things other than inlay hints,
 // e.g. signature hints above the line, pipeline hints on the side and so on.
 
-[<Export(typeof<IFSharpInlineHintsService>)>]
+[<Export(typeof<IFSharpInlineHintsService2>)>]
 type internal FSharpInlayHintsService [<ImportingConstructor>] (settings: EditorOptions) =
 
     static let userOpName = "Hints"
 
-    interface IFSharpInlineHintsService with
-        member _.GetInlineHintsAsync(document, _, cancellationToken) =
-            let hintKinds = OptionParser.getHintKinds settings.Advanced
+    interface IFSharpInlineHintsService2 with
+        member _.GetInlineHintsAsync(document, textSpan, displayAllOverride, cancellationToken) =
+            let hintKinds =
+                if displayAllOverride then
+                    Hints.allHintKinds
+                else
+                    OptionParser.getHintKinds settings.Advanced
 
             if hintKinds.IsEmpty then
                 Task.FromResult ImmutableArray.Empty
@@ -31,14 +34,13 @@ type internal FSharpInlayHintsService [<ImportingConstructor>] (settings: Editor
                     let! cancellationToken = CancellableTask.getCancellationToken ()
 
                     let! sourceText = document.GetTextAsync cancellationToken
-                    let! nativeHints = HintService.getHintsForDocument sourceText document hintKinds userOpName
+                    let! nativeHints = HintService.getHintsForDocument sourceText document hintKinds textSpan userOpName
 
-                    let tasks =
+                    let roslynHints =
                         nativeHints
-                        |> Seq.map (fun hint -> NativeToRoslynHintConverter.convert sourceText hint cancellationToken)
-
-                    let! roslynHints = Task.WhenAll(tasks)
+                        |> Seq.map (NativeToRoslynHintConverter.convert sourceText)
+                        |> ImmutableArray.CreateRange
 
-                    return roslynHints.ToImmutableArray()
+                    return roslynHints
                 }
                 |> CancellableTask.start cancellationToken

vsintegration/src/FSharp.Editor/Hints/HintService.fs

@@ -39,7 +39,7 @@ module HintService =
         let hints = getHints sourceText parseResults hintKinds symbolUses symbol
         Seq.concat hints
 
-    let getHintsForDocument sourceText (document: Document) hintKinds userOpName =
+    let getHintsForDocument (sourceText: SourceText) (document: Document) hintKinds (textSpan: TextSpan) userOpName =
         cancellableTask {
             if isSignatureFile document.FilePath then
                 return List.empty
@@ -75,3 +75,8 @@ module HintService =
 
                     return nativeHints
         }
+        |> CancellableTask.map (
+            List.filter (fun hint ->
+                let hintSpan = RoslynHelpers.FSharpRangeToTextSpan(sourceText, hint.Range)
+                textSpan.IntersectsWith hintSpan)
+        )

vsintegration/src/FSharp.Editor/Hints/Hints.fs

@@ -14,6 +14,9 @@ module Hints =
         | ParameterNameHint
         | ReturnTypeHint
 
+    let allHintKinds =
+        Set [ HintKind.TypeHint; HintKind.ParameterNameHint; HintKind.ReturnTypeHint ]
+
     // Relatively convenient for testing
     type NativeHint =
         {

vsintegration/src/FSharp.Editor/Hints/NativeToRoslynHintConverter.fs

@@ -33,9 +33,7 @@ module NativeToRoslynHintConverter =
             }
             |> CancellableTask.start ct
 
-        cancellableTask {
-            let span = rangeToSpan hint.Range sourceText
-            let displayParts = hint.Parts |> Seq.map nativeToRoslynText
+        let span = rangeToSpan hint.Range sourceText
+        let displayParts = hint.Parts |> Seq.map nativeToRoslynText
 
-            return FSharpInlineHint(span, displayParts.ToImmutableArray(), getDescriptionAsync)
-        }
+        FSharpInlineHint(span, displayParts.ToImmutableArray(), getDescriptionAsync)

vsintegration/tests/FSharp.Editor.Tests/Hints/HintTestFramework.fs

@@ -3,6 +3,7 @@
 namespace FSharp.Editor.Tests.Hints
 
 open Microsoft.CodeAnalysis
+open Microsoft.CodeAnalysis.Text
 open Microsoft.VisualStudio.FSharp.Editor
 open Microsoft.VisualStudio.FSharp.Editor.Hints
 open Hints
@@ -47,7 +48,8 @@ module HintTestFramework =
                     }
 
                 let! sourceText = document.GetTextAsync ct |> Async.AwaitTask
-                let! hints = HintService.getHintsForDocument sourceText document hintKinds "test" ct
+                let textSpan = TextSpan(0, sourceText.Length)
+                let! hints = HintService.getHintsForDocument sourceText document hintKinds textSpan "test" ct
                 let! tooltips = hints |> Seq.map getTooltip |> Async.Parallel
                 return tooltips |> Seq.zip hints |> Seq.map convert
             }