Add codefix for redundant attribute suffix.

src/FsAutoComplete/CodeFixes/RemoveRedundantAttributeSuffix.fs

@@ -0,0 +1,53 @@
+module FsAutoComplete.CodeFix.RemoveRedundantAttributeSuffix
+
+open FSharp.Compiler.Syntax
+open FsToolkit.ErrorHandling
+open FsAutoComplete.CodeFix.Types
+open Ionide.LanguageServerProtocol.Types
+open FsAutoComplete
+open FsAutoComplete.LspHelpers
+
+let title = "Remove redundant attribute suffix"
+
+let fix (getParseResultsForFile: GetParseResultsForFile) : CodeFix =
+  fun codeActionParams ->
+    asyncResult {
+      let filePath = codeActionParams.TextDocument.GetFilePath() |> Utils.normalizePath
+      let fcsPos = protocolPosToPos codeActionParams.Range.Start
+      let! parseAndCheck, _, _ = getParseResultsForFile filePath fcsPos
+
+      let isAttributeWithRedundantSuffix =
+        SyntaxTraversal.Traverse(
+          fcsPos,
+          parseAndCheck.GetParseResults.ParseTree,
+          { new SyntaxVisitorBase<_>() with
+              member _.VisitAttributeApplication(path, attributes) =
+                let attributesWithRedundantSuffix =
+                  attributes.Attributes
+                  |> List.choose (fun a ->
+                    match List.tryLast a.TypeName.LongIdent with
+                    | Some ident when ident.idText.EndsWith("Attribute") -> Some ident
+                    | _ -> None)
+
+                if List.isEmpty attributesWithRedundantSuffix then
+                  None
+                else
+                  Some attributesWithRedundantSuffix }
+        )
+
+      match isAttributeWithRedundantSuffix with
+      | None -> return []
+      | Some redundantSuffixIdents ->
+        return
+          redundantSuffixIdents
+          |> List.map (fun ident ->
+            let updateText = ident.idText.Replace("Attribute", "")
+
+            { Edits =
+                [| { Range = fcsRangeToLsp ident.idRange
+                     NewText = updateText } |]
+              File = codeActionParams.TextDocument
+              Title = title
+              SourceDiagnostic = None
+              Kind = FixKind.Refactor })
+    }

src/FsAutoComplete/LspServers/AdaptiveFSharpLspServer.fs

@@ -1686,6 +1686,7 @@ type AdaptiveFSharpLspServer
          ConvertPositionalDUToNamed.fix tryGetParseResultsForFile getRangeText
          ConvertTripleSlashCommentToXmlTaggedDoc.fix tryGetParseResultsForFile getRangeText
          GenerateXmlDocumentation.fix tryGetParseResultsForFile
+         RemoveRedundantAttributeSuffix.fix tryGetParseResultsForFile
          Run.ifEnabled
            (fun _ -> config.AddPrivateAccessModifier)
            (AddPrivateAccessModifier.fix tryGetParseResultsForFile symbolUseWorkspace)

src/FsAutoComplete/LspServers/FsAutoComplete.Lsp.fs

@@ -1223,6 +1223,7 @@ type FSharpLspServer(state: State, lspClient: FSharpLspClient, sourceTextFactory
              ConvertPositionalDUToNamed.fix tryGetParseResultsForFile getRangeText
              ConvertTripleSlashCommentToXmlTaggedDoc.fix tryGetParseResultsForFile getRangeText
              GenerateXmlDocumentation.fix tryGetParseResultsForFile
+             RemoveRedundantAttributeSuffix.fix tryGetParseResultsForFile
              Run.ifEnabled
                (fun _ -> config.AddPrivateAccessModifier)
                (AddPrivateAccessModifier.fix tryGetParseResultsForFile symbolUseWorkspace)

test/FsAutoComplete.Tests.Lsp/CodeFixTests/Tests.fs

@@ -2777,6 +2777,102 @@ let private wrapExpressionInParenthesesTests state =
         selectCodeFix
   ])
 
+let private removeRedundantAttributeSuffixTests state =
+  serverTestList (nameof RemoveRedundantAttributeSuffix) state defaultConfigDto None (fun server ->
+    [ let selectCodeFix = CodeFix.withTitle RemoveRedundantAttributeSuffix.title
+
+      testCaseAsync "redundant attribute suffix in let binding"
+      <| CodeFix.check
+        server
+        """
+        open System
+
+        [<ObsoleteAttribute$0("Meh")>]
+        let f x y = x + y
+        """
+        Diagnostics.acceptAll
+        selectCodeFix
+        """
+        open System
+
+        [<Obsolete("Meh")>]
+        let f x y = x + y
+        """
+
+      testCaseAsync "redundant attribute suffix on type definition"
+      <| CodeFix.check
+        server
+        """
+        open System
+
+        type FooAttribute() = inherit Attribute()
+
+        [<FooAttribute$0>]
+        type A =
+            class end
+        """
+        Diagnostics.acceptAll
+        selectCodeFix
+        """
+        open System
+
+        type FooAttribute() = inherit Attribute()
+
+        [<Foo>]
+        type A =
+            class end
+        """
+
+      testCaseAsync "redundant attribute suffix with target and constructor"
+      <| CodeFix.check
+        server
+        """
+        open System
+
+        type FooAttribute() = inherit Attribute()
+
+        [<type: FooAttribute$0()>]
+        type A =
+            class end
+        """
+        Diagnostics.acceptAll
+        selectCodeFix
+        """
+        open System
+
+        type FooAttribute() = inherit Attribute()
+
+        [<type: Foo()>]
+        type A =
+            class end
+        """
+
+      testCaseAsync "redundant attribute suffix in multiple attributes"
+      <| CodeFix.check
+        server
+        """
+        open System
+
+        type FooAttribute() = inherit Attribute()
+        type BarAttribute() = inherit Attribute()
+
+        [<FooAttribute$0; Bar>]
+        type A =
+            class end
+        """
+        Diagnostics.acceptAll
+        selectCodeFix
+        """
+        open System
+
+        type FooAttribute() = inherit Attribute()
+        type BarAttribute() = inherit Attribute()
+
+        [<Foo; Bar>]
+        type A =
+            class end
+        """ ])
+
 let tests state = testList "CodeFix-tests" [
   HelpersTests.tests
 
@@ -2819,4 +2915,5 @@ let tests state = testList "CodeFix-tests" [
   useMutationWhenValueIsMutableTests state
   useTripleQuotedInterpolationTests state
   wrapExpressionInParenthesesTests state
+  removeRedundantAttributeSuffixTests state
 ]