From 9277ff9c2aaf2fbdc9867b76b3f067e0d01822e0 Mon Sep 17 00:00:00 2001
From: dawe <dawedawe@posteo.de>
Date: Fri, 24 Jan 2025 16:41:03 +0100
Subject: [PATCH] fix func signature for empty param names (#1351)

* fix func signature for empty param names

* add testcase
---
 src/FsAutoComplete.Core/SignatureFormatter.fs         |  8 +++++++-
 test/FsAutoComplete.Tests.Lsp/CoreTests.fs            | 11 +++++++++--
 .../TestCases/Tooltips/Script.fsx                     |  4 ++++
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/FsAutoComplete.Core/SignatureFormatter.fs b/src/FsAutoComplete.Core/SignatureFormatter.fs
index 2662e0c5c..c79e34433 100644
--- a/src/FsAutoComplete.Core/SignatureFormatter.fs
+++ b/src/FsAutoComplete.Core/SignatureFormatter.fs
@@ -505,7 +505,13 @@ module SignatureFormatter =
           many
           |> List.map (fun (paramTypes) ->
             paramTypes
-            |> List.map (fun p -> formatName p + ":" ++ (formatParameter p))
+            |> List.map (fun p ->
+              let paramName = formatName p
+
+              if String.IsNullOrWhiteSpace(paramName) then
+                formatParameter p
+              else
+                paramName + ":" ++ (formatParameter p))
             |> String.concat (" * "))
           |> String.concat (" -> ")
 
diff --git a/test/FsAutoComplete.Tests.Lsp/CoreTests.fs b/test/FsAutoComplete.Tests.Lsp/CoreTests.fs
index 0ef83eb6f..2595a8d22 100644
--- a/test/FsAutoComplete.Tests.Lsp/CoreTests.fs
+++ b/test/FsAutoComplete.Tests.Lsp/CoreTests.fs
@@ -461,12 +461,19 @@ let tooltipTests state =
 #if NET8_0
               [ "active pattern ValueWithName: "
                 "   input: Expr"
-                "       -> option<obj * System.Type * string>" ]) ] ]
+                "       -> option<obj * System.Type * string>" ])
 #else
               [ "active pattern ValueWithName: "
                 "   input: Expr"
-                "       -> option<objnull * System.Type * string>" ]) ] ]
+                "       -> option<objnull * System.Type * string>" ])
 #endif
+          verifySignature
+            96u
+            7u
+            (concatLines
+              [ "interface IWithAndWithoutParamNames"
+                "  abstract member WithParamNames: arg1: int * arg2: float -> string"
+                "  abstract member WithoutParamNames: int * string -> int" ]) ] ]
 
 let closeTests state =
   // Note: clear diagnostics also implies clear caches (-> remove file & project options from State).
diff --git a/test/FsAutoComplete.Tests.Lsp/TestCases/Tooltips/Script.fsx b/test/FsAutoComplete.Tests.Lsp/TestCases/Tooltips/Script.fsx
index e20699b62..a36c69ed5 100644
--- a/test/FsAutoComplete.Tests.Lsp/TestCases/Tooltips/Script.fsx
+++ b/test/FsAutoComplete.Tests.Lsp/TestCases/Tooltips/Script.fsx
@@ -93,3 +93,7 @@ type Awaitable =
       (awaitable: 'Awaitable)
       =
       awaitable.GetAwaiter()
+
+type IWithAndWithoutParamNames =
+    abstract member WithParamNames : arg1: int * arg2: float -> string
+    abstract member WithoutParamNames : int * string -> int