Bug: assert(not coroutine.running()) in sync API

[linrongbin16]

Hi,

In current implementation, there is an issue: linrongbin16/gitlinker.nvim#257

@loganswartz found it is always failed on this line (on fedora 41, but worked on MacOS M1 and ubuntu 20.04):

https://github.com/linrongbin16/gitlinker.nvim/blob/df0c4e342742812186f87e32caf82b3e5e288a84/lua/gitlinker/commons/async.lua#L78

Note: it is copied from here:

async.nvim/lua/async.lua

Line 77 in ad097c9

assert(not coroutine.running())

I found the comments says there is a API break change in coroutine.running() between lua51 and lua52:

async.nvim/lua/async.lua

Lines 16 to 23 in ad097c9

	-- Coroutine.running() was changed between Lua 5.1 and 5.2:
	-- - 5.1: Returns the running coroutine, or nil when called by the main thread.
	-- - 5.2: Returns the running coroutine plus a boolean, true when the running
	-- coroutine is the main one.
	--
	-- For LuaJIT, 5.2 behaviour is enabled with LUAJIT_ENABLE_LUA52COMPAT
	--
	-- We need to handle both.

In a previous version, there's a M.running() to handle this:

-- Note: coroutine.running() was changed between Lua 5.1 and 5.2:
-- - 5.1: Returns the running coroutine, or nil when called by the main thread.
-- - 5.2: Returns the running coroutine plus a boolean, true when the running
--   coroutine is the main one.
--
-- For LuaJIT, 5.2 behaviour is enabled with LUAJIT_ENABLE_LUA52COMPAT
--
-- We need to handle both.
--- Returns whether the current execution context is async.
---
--- @treturn boolean?
function M.running()
  local current = coroutine.running()
  if current and handles[current] then
    return true
  end
end

And there is a strict parameter to tolerate some errors:

--- Create a function which executes in an async context but
--- called from a non-async context.
--- @tparam function func
--- @tparam boolean strict Error when called in non-async context
function M.void(func, strict)
  vim.validate({ func = { func, "function" } })
  return function(...)
    if M.running() then
      if strict then
        error("This function must run in a non-async context")
      end
      return func(...)
    end
    return M.run(func, nil, ...)
  end
end

[linrongbin16]

I just reproduced this bug in linrongbin16/gitlinker.nvim#262, I think it worth some attention.

[lewis6991]

This repo is in the process of a complete rewrite so this issue might not apply after that.

[linrongbin16]

This repo is in the process of a complete rewrite so this issue might not apply after that.

Thank you for the updates!

[lewis6991]

I've merged in all the v2 code now. It's not yet finished, but is much higher quality than what was on main before.