activeParameter should be uinteter

LuaLS#1751

Author: sumneko

changelog.md

@@ -3,9 +3,11 @@
 ## 3.6.5
 * `FIX` [#831]
 * `FIX` [#1729]
+* `FIX` [#1751]
 
 [#831]:  https://github.com/sumneko/lua-language-server/issues/831
 [#1729]: https://github.com/sumneko/lua-language-server/issues/1729
+[#1751]: https://github.com/sumneko/lua-language-server/issues/1751
 
 `2022-11-29`
 ## 3.6.4

script/provider/provider.lua

@@ -797,7 +797,7 @@ m.register 'textDocument/signatureHelp' {
             infos[i] = {
                 label           = result.label,
                 parameters      = parameters,
-                activeParameter = result.index - 1,
+                activeParameter = math.max(0, result.index - 1),
                 documentation   = result.description and {
                     value = tostring(result.description),
                     kind  = 'markdown',