fix out-of-bounds checking for completions

src/FsAutoComplete.Core/KeywordList.fs

@@ -48,8 +48,9 @@ module KeywordList =
         |> Seq.toArray
 
     let allKeywords : string list =
-        FSharpKeywords.KeywordsWithDescription
-        |> List.map fst
+        keywordDescriptions
+        |> Seq.map ((|KeyValue|) >> fst)
+        |> Seq.toList
 
     let keywordCompletionItems =
         allKeywords

src/FsAutoComplete/FsAutoComplete.Lsp.fs

@@ -25,6 +25,7 @@ open CliWrap.Buffered
 open FSharp.Compiler.Tokenization
 open FSharp.Compiler.EditorServices
 open FSharp.Compiler.Symbols
+open FSharp.UMX
 
 module FcsRange = FSharp.Compiler.Text.Range
 type FcsRange = FSharp.Compiler.Text.Range
@@ -1041,18 +1042,12 @@ type FSharpLspServer(backgroundServiceEnabled: bool, state: State, lspClient: FS
         commands.TryGetFileCheckerOptionsWithLines file
         |> Result.mapError JsonRpc.Error.InternalErrorMessage
 
-      let line, col = p.Position.Line, p.Position.Character
-      let lineStr = lines.GetLineString line
-
-      let word =
-        lineStr.Substring(0, min col lineStr.Length)
-
-      do! ensureInBounds lines (line, col)
+      let lineSegmentLSPRange =
+        { Start = { p.Position with Character = 0}; End = p.Position }
+      let lineSegmentFCSRange = protocolRangeToRange (UMX.untag file) lineSegmentLSPRange
+      let! lineStr = lines.GetText lineSegmentFCSRange |> Result.mapError JsonRpc.Error.InternalErrorMessage
 
-      if (lineStr.StartsWith "#"
-          && (KeywordList.hashDirectives.Keys
-              |> Seq.exists (fun k -> k.StartsWith word)
-              || word.Contains "\n")) then
+      if lineStr.StartsWith "#" then
         let completionList =
           { IsIncomplete = false
             Items = KeywordList.hashSymbolCompletionItems }

test/FsAutoComplete.Tests.Lsp/CompletionTests.fs

@@ -41,6 +41,46 @@ let tests state =
       | Error e ->
         failtestf "Got an error while retrieving completions: %A" e
     })
+
+    testCaseAsync "completion at start of line" (async {
+      let! server, path = server
+      let completionParams : CompletionParams =
+        {
+          TextDocument = { Uri = Path.FilePathToUri path }
+          Position = { Line = 6; Character = 5 } // the '.' in 'List.'
+          Context = Some { triggerKind = CompletionTriggerKind.TriggerCharacter; triggerCharacter = Some '.' }
+        }
+      let! response = server.TextDocumentCompletion completionParams
+      match response with
+      | Ok (Some completions) ->
+        Expect.equal completions.Items.Length 106 "at time of writing the List module has 106 exposed members"
+        let firstItem = completions.Items.[0]
+        Expect.equal firstItem.Label "Empty" "first member should be List.Empty, since properties are preferred over functions"
+      | Ok None ->
+        failtest "Should have gotten some completion items"
+      | Error e ->
+        failtestf "Got an error while retrieving completions: %A" e
+    })
+
+    testCaseAsync "completion at end of line" (async {
+      let! server, path = server
+      let completionParams : CompletionParams =
+        {
+          TextDocument = { Uri = Path.FilePathToUri path }
+          Position = { Line = 8; Character = 16 } // the '.' in 'List.'
+          Context = Some { triggerKind = CompletionTriggerKind.TriggerCharacter; triggerCharacter = Some '.' }
+        }
+      let! response = server.TextDocumentCompletion completionParams
+      match response with
+      | Ok (Some completions) ->
+        Expect.equal completions.Items.Length 106 "at time of writing the List module has 106 exposed members"
+        let firstItem = completions.Items.[0]
+        Expect.equal firstItem.Label "Empty" "first member should be List.Empty, since properties are preferred over functions"
+      | Ok None ->
+        failtest "Should have gotten some completion items"
+      | Error e ->
+        failtestf "Got an error while retrieving completions: %A" e
+    })
   ]
 
   ///Tests for getting autocomplete
@@ -243,7 +283,7 @@ let autoOpenTests state =
         return (edit, ns, openPos)
     | Ok _ -> return failtest $"Quick fix on `{word}` doesn't contain open action"
   }
-  
+
   let test (compareWithQuickFix: bool) (name: string option) (server: Async<FSharpLspServer * string>) (word: string, ns: string) (cursor: Position) (expectedOpen: Position) pending =
     let name = name |> Option.defaultWith (fun _ -> sprintf "completion on `Regex` at (%i, %i) should `open System.Text.RegularExpressions` at (%i, %i) (0-based)" (cursor.Line) (cursor.Character) (expectedOpen.Line) (expectedOpen.Character))
     let runner = if pending then ptestCaseAsync else testCaseAsync
@@ -369,7 +409,7 @@ let autoOpenTests state =
           do! server.Shutdown()
         })
     ]
-  
+
   let ptestScript name scriptName =
     testList name [
       let scriptPath = Path.Combine(dirPath, scriptName)

test/FsAutoComplete.Tests.Lsp/TestCases/Completion/Script.fsx

@@ -2,3 +2,8 @@ async {
     return 1
 }
 |> Async. // completion at this `.` should not have a billion suggestions
+
+
+List.
+
+let tail = List.