fix(hover/#3231): Part 1 - Hover not showing up in some cases (#3390)

__Issue:__ For some extensions, diagnostics would show the squiggly underline the editor, but wouldn't show any details in the hover UI (like in #3231 )

__Defect:__ Some extensions don't send a diagnostic range - they send a position, and the editor is supposed to treat the diagnostic as spanning the _token_ at the range. We were handling that correctly for rendering, but for the hover, Onivim wasn't detecting positions as being in that implicit range.

__Fix:__ Handle hover in this case - find all diagnostics in the token range, and show in the hover ui.

CHANGES_CURRENT.md

@@ -42,6 +42,7 @@
 - #3382 - Input: Handle `<capslock>` key
 - #3389 - Editor: Render diagnostics with squiggly lines (fixes #2827)
 - #3394 - Extensions: Fix error parsing extension manifest with boolean when express (related #3388)
+- #3390 - Diagnostics: Some diagnostics wouldn't show in hover UI (related #3231)
 
 ### Performance
 

src/Core/Buffer.re

@@ -216,6 +216,45 @@ let characterRangeAt = (line, buffer) => {
      });
 };
 
+let getNumberOfLines = (buffer: t) => Array.length(buffer.lines);
+
+let tokenAt = (~languageConfiguration, position: CharacterPosition.t, buffer) => {
+  let line = position.line;
+  let character = position.character;
+  let lineNumber = line |> EditorCoreTypes.LineNumber.toZeroBased;
+  let numberOfLines = getNumberOfLines(buffer);
+
+  if (lineNumber < 0 || lineNumber >= numberOfLines) {
+    None;
+  } else {
+    let bufferLine = getLine(lineNumber, buffer);
+    let f = uchar =>
+      LanguageConfiguration.isWordCharacter(uchar, languageConfiguration);
+    let startIndex =
+      BufferLine.traverse(
+        ~f,
+        ~direction=`Backwards,
+        ~index=character,
+        bufferLine,
+      )
+      |> Option.value(~default=character);
+    let stopIndex =
+      BufferLine.traverse(
+        ~f,
+        ~direction=`Forwards,
+        ~index=character,
+        bufferLine,
+      )
+      |> Option.value(~default=character);
+    Some(
+      CharacterRange.{
+        start: CharacterPosition.{line, character: startIndex},
+        stop: CharacterPosition.{line, character: stopIndex},
+      },
+    );
+  };
+};
+
 let lastLine = buffer => {
   buffer.lines |> Array.length |> max(1) |> LineNumber.ofOneBased;
 };
@@ -245,8 +284,6 @@ let getUri = (buffer: t) => {
   };
 };
 
-let getNumberOfLines = (buffer: t) => Array.length(buffer.lines);
-
 let characterRange = (buffer: t) => {
   let start =
     CharacterPosition.{line: LineNumber.zero, character: CharacterIndex.zero};

src/Core/Buffer.rei

@@ -70,6 +70,10 @@ let hasTrailingNewLine: t => bool;
 let rawLine: (LineNumber.t, t) => option(string);
 let characterRangeAt: (LineNumber.t, t) => option(CharacterRange.t);
 
+let tokenAt:
+  (~languageConfiguration: LanguageConfiguration.t, CharacterPosition.t, t) =>
+  option(CharacterRange.t);
+
 let lastLine: t => LineNumber.t;
 
 let getVersion: t => int;

src/Feature/Diagnostics/Feature_Diagnostics.re

@@ -268,6 +268,12 @@ let getDiagnosticsAtPosition = (instance, buffer, position) => {
        CharacterRange.contains(position, range)
      );
 };
+let getDiagnosticsInRange = (model, buffer, query) => {
+  getDiagnostics(model, buffer)
+  |> List.filter((Diagnostic.{range, _}) =>
+       CharacterRange.intersects(query, range)
+     );
+};
 
 let getDiagnosticsMap = (instance, buffer) => {
   getDiagnostics(instance, buffer) |> Internal.explodeDiagnostics(buffer);

src/Feature/Diagnostics/Feature_Diagnostics.rei

@@ -74,6 +74,8 @@ let moveMarkers:
 let getDiagnostics: (model, Buffer.t) => list(Diagnostic.t);
 let getDiagnosticsAtPosition:
   (model, Buffer.t, CharacterPosition.t) => list(Diagnostic.t);
+let getDiagnosticsInRange:
+  (model, Buffer.t, CharacterRange.t) => list(Diagnostic.t);
 let getDiagnosticsMap: (model, Buffer.t) => IntMap.t(list(Diagnostic.t));
 
 let getAllDiagnostics: model => list((Uri.t, Diagnostic.t));

src/Feature/Editor/Editor.re

@@ -1338,39 +1338,8 @@ let getLeftVisibleColumn = view => {
 };
 
 let getTokenAt =
-    (~languageConfiguration, {line, character}: CharacterPosition.t, editor) => {
-  let lineNumber = line |> EditorCoreTypes.LineNumber.toZeroBased;
-
-  if (lineNumber < 0
-      || lineNumber >= EditorBuffer.numberOfLines(editor.buffer)) {
-    None;
-  } else {
-    let bufferLine = EditorBuffer.line(lineNumber, editor.buffer);
-    let f = uchar =>
-      LanguageConfiguration.isWordCharacter(uchar, languageConfiguration);
-    let startIndex =
-      BufferLine.traverse(
-        ~f,
-        ~direction=`Backwards,
-        ~index=character,
-        bufferLine,
-      )
-      |> Option.value(~default=character);
-    let stopIndex =
-      BufferLine.traverse(
-        ~f,
-        ~direction=`Forwards,
-        ~index=character,
-        bufferLine,
-      )
-      |> Option.value(~default=character);
-    Some(
-      CharacterRange.{
-        start: CharacterPosition.{line, character: startIndex},
-        stop: CharacterPosition.{line, character: stopIndex},
-      },
-    );
-  };
+    (~languageConfiguration, position: CharacterPosition.t, editor) => {
+  EditorBuffer.tokenAt(~languageConfiguration, position, editor.buffer);
 };
 
 let getContentPixelWidth = editor => {

src/Feature/Editor/EditorBuffer.re

@@ -15,3 +15,5 @@ let hasLine = (lineNumber, buffer) => {
   let lineCount = numberOfLines(buffer);
   lineIdx >= 0 && lineIdx < lineCount;
 };
+
+let tokenAt = Oni_Core.Buffer.tokenAt;

src/Feature/Editor/EditorBuffer.rei

@@ -1,15 +1,21 @@
+open EditorCoreTypes;
+open Oni_Core;
 // EditorBuffer is a subset of the buffer model,
 // specifically containing the functions and data
 // needed by the editor surface.
 
 type t;
 
-let ofBuffer: Oni_Core.Buffer.t => t;
+let ofBuffer: Buffer.t => t;
 let id: t => int;
 let getEstimatedMaxLineLength: t => int;
 let numberOfLines: t => int;
-let line: (int, t) => Oni_Core.BufferLine.t;
+let line: (int, t) => BufferLine.t;
 let hasLine: (EditorCoreTypes.LineNumber.t, t) => bool;
-let font: t => Oni_Core.Font.t;
-let fileType: t => Oni_Core.Buffer.FileType.t;
+let font: t => Font.t;
+let fileType: t => Buffer.FileType.t;
 let measure: (Uchar.t, t) => float;
+
+let tokenAt:
+  (~languageConfiguration: LanguageConfiguration.t, CharacterPosition.t, t) =>
+  option(CharacterRange.t);

src/Feature/Editor/EditorSurface.re

@@ -278,11 +278,10 @@ let%component make =
         ~uiFont,
         ~editorFont,
         ~model=languageSupport,
-        ~diagnostics,
         ~tokenTheme,
         ~grammars=grammarRepository,
         ~buffer,
-        ~editorId=Some(editorId),
+        ~editorId,
         ~languageInfo,
       );
 

src/Feature/LanguageSupport/Feature_LanguageSupport.re

@@ -153,6 +153,7 @@ module Msg = {
 let update =
     (
       ~config,
+      ~diagnostics,
       ~extensions,
       ~languageConfiguration,
       ~maybeSelection,
@@ -488,7 +489,9 @@ let update =
   | Hover(hoverMsg) =>
     let (hover', outMsg) =
       Hover.update(
+        ~languageConfiguration,
         ~cursorLocation,
+        ~diagnostics,
         ~maybeBuffer,
         ~editorId,
         ~extHostClient=client,
@@ -897,7 +900,6 @@ module Hover = {
   module Popup = {
     let make =
         (
-          ~diagnostics,
           ~theme,
           ~tokenTheme,
           ~languageInfo,
@@ -910,7 +912,6 @@ module Hover = {
         ) => {
       let {hover, _} = model;
       OldHover.Popup.make(
-        ~diagnostics,
         ~theme,
         ~tokenTheme,
         ~languageInfo,

src/Feature/LanguageSupport/Feature_LanguageSupport.rei

@@ -96,6 +96,7 @@ type outmsg =
 let update:
   (
     ~config: Oni_Core.Config.resolver,
+    ~diagnostics: Feature_Diagnostics.model,
     ~extensions: Feature_Extensions.model,
     ~languageConfiguration: Oni_Core.LanguageConfiguration.t,
     ~maybeSelection: option(CharacterRange.t),
@@ -283,7 +284,6 @@ module Hover: {
   module Popup: {
     let make:
       (
-        ~diagnostics: Feature_Diagnostics.model,
         ~theme: Oni_Core.ColorTheme.Colors.t,
         ~tokenTheme: Oni_Syntax.TokenTheme.t,
         ~languageInfo: Exthost.LanguageInfo.t,
@@ -292,7 +292,7 @@ module Hover: {
         ~grammars: Oni_Syntax.GrammarRepository.t,
         ~model: model,
         ~buffer: Oni_Core.Buffer.t,
-        ~editorId: option(int)
+        ~editorId: int
       ) =>
       option((CharacterPosition.t, list(Oni_Components.Popup.Section.t)));
   };