<afile> cannot be expanded when running with -V1 about neovim

[wookayin]

From :help expand()

  When 'verbose' is set then expanding '%', '#' and <> items
  will result in an error message if the argument cannot be
  expanded.

Per the documentation, it is not quite clear whether printing error message should result in the Lua executor throwing Error (which is the current implementation) or shouldn't interfere with the control flow. So I assumed this is by design (from upstream vim).

For the record, this behavior has been there since Neovim 0.8.0 -- it was not throwing an error before (a9e6cf0). Ref #19905

A possible workaround is: (see also nvim-neo-tree/neo-tree.nvim#1145 (comment))

-- Simply ignore expand(...) error when &verbose>0
local function safe_expand(args)
  if vim.o.verbose > 0 then
    return vim.F.npcall(vim.fn.expand, args) or ''
  else
    return vim.fn.expand(args)
  end
end

[stevearc]

Ah, so the idea is that expanding <afile> is actually "failing" in the normal case by expanding to the empty string, and that with -V1 it is intentionally throwing an error instead. I don't love that changing the verbosity affects control flow, but agree that it makes sense to align with upstream vim.

Thanks for the clarification!