Infer pcall arguments from the first function parameter

[cryi]

Hi 👋

I was wondering if it would be possible for LuaLS to infer the types of the arguments passed to pcall based on the signature of its first function argument. This would significantly improve developer experience, especially when working with typed Lua (e.g., EmmyLua annotations) or when relying on auto-completion and type checking.

Example:

local function greet(name: string)
  print("Hello, " .. name)
end

pcall(greet, "world") 
             ^- here we should see `name: string`

In this case, it would be great if LuaLS could infer that greet expects a string, and therefore type-check or suggest "world" accordingly when passed to pcall.

Currently, the parameters after the first one are not checked or suggested with much context, making it less ergonomic when using pcall (or other similar functions) for safe calls.

[CppCXY]

you can try the emmylua_ls，it support this feature

[cryi]

@CppCXY what about #3017 ? I prefer something without JDK. Less dependencies = better, 🙂

[CppCXY]

@CppCXY what about #3017 ? I prefer something without JDK. Less dependencies = better, 🙂

no emmylua ls is write in rust：https://github.com/CppCXY/emmylua-analyzer-rust

[cryi]

Ah ok. I thought you meant this one EmmyLua-LanguageServer.

I will give it a shot. Thank you @CppCXY .

[cryi]

Indeed it works @CppCXY. Cool stuff. But I wonder could we get autocomplete as well? Right now it just warns about the mismatch but does not present the arguments when typing.

See