Failed to load merlin in vim

[mdesharnais]

After installing merlin:

$ opam list --installed | grep -F merlin
merlin              3.0.5  Editor helper, provides completion, typing and source

I configured vim with:

$ opam user-setup install
ocamltop > base > .ocamlinit: up to date
vim > .vimrc: already exists, not installing base template
vim > base > .vimrc: up to date

And get this error message when opening a file with vim:

":merlin-log:" [New File]
Error detected while processing function merlin#Register[133]..merlin#LoadProject:
line    2:
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/MDS7/.opam/4.06.0/share/merlin/vim/autoload/merlin.py", line 730, in setup_merlin
    result = command("check-configuration")
  File "/home/MDS7/.opam/4.06.0/share/merlin/vim/autoload/merlin.py", line 188, in command
    return command2(args)
  File "/home/MDS7/.opam/4.06.0/share/merlin/vim/autoload/merlin.py", line 181, in command2
    raise Failure(value)
merlin.Failure: u'abnormal termination'
Press ENTER or type command to continue

My .vimrc is:

set number
set tabstop=2 shiftwidth=2 softtabstop=0 expandtab smarttab
set smartindent
set listchars=trail:¤,nbsp:~,tab:>-
set list
set ignorecase
set smartcase
" ## added by OPAM user-setup for vim / base ## 93ee63e278bdfc07d1139a748ed3fff2 ## you can edit, but keep this line
let s:opam_share_dir = system("opam config var share")
let s:opam_share_dir = substitute(s:opam_share_dir, '[\r\n]*$', '', '')

let s:opam_configuration = {}

function! OpamConfOcpIndent()
  execute "set rtp^=" . s:opam_share_dir . "/ocp-indent/vim"
endfunction
let s:opam_configuration['ocp-indent'] = function('OpamConfOcpIndent')

function! OpamConfOcpIndex()
  execute "set rtp+=" . s:opam_share_dir . "/ocp-index/vim"
endfunction
let s:opam_configuration['ocp-index'] = function('OpamConfOcpIndex')

function! OpamConfMerlin()
  let l:dir = s:opam_share_dir . "/merlin/vim"
  execute "set rtp+=" . l:dir
endfunction
let s:opam_configuration['merlin'] = function('OpamConfMerlin')

let s:opam_packages = ["ocp-indent", "ocp-index", "merlin"]
let s:opam_check_cmdline = ["opam list --installed --short --safe --color=never"] + s:opam_packages
let s:opam_available_tools = split(system(join(s:opam_check_cmdline)))
for tool in s:opam_packages
  " Respect package order (merlin should be after ocp-index)
  if count(s:opam_available_tools, tool) > 0
    call s:opam_configuration[tool]()
  endif
endfor
" ## end of OPAM user-setup addition for vim / base ## keep this line

[ArchangeGabriel]

Same issue here, with a much simpler .vimrc:

filetype plugin indent on
syntax on
set number
set nocompatible
set wildmenu
set wrapscan
set tabstop=4
set expandtab
set shiftwidth=4
set breakindent
set smartindent
set nojoinspaces

[ArchangeGabriel]

My exact log:

Error detected while processing function merlin#Register[133]..merlin#LoadProject:
line    2:
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/share/vim/vimfiles/autoload/merlin.py", line 730, in setup_merlin
    result = command("check-configuration")
  File "/usr/share/vim/vimfiles/autoload/merlin.py", line 188, in command
    return command2(args)
  File "/usr/share/vim/vimfiles/autoload/merlin.py", line 181, in command2
    raise Failure(value)
merlin.Failure: u'abnormal termination'

[cyr-l]

I don't know if you managed to resolve your issue but this could come from the fact that you're not using the required OCaml version (version 4.02.3 at the time of writing).

[ArchangeGabriel]

I’m using 4.06.0. But following the doc you’ve pointed, I’ve got interesting results running ocamlmerlin -version:

Fatal error: exception Failure("Config file not found - neither /etc/findlib.conf nor the directory /etc/findlib.conf.d")

[ArchangeGabriel]

Prefixing with OCAMLFIND_CONF=/dev/null as advised in https://github.com/ocaml/merlin/issues/551 returned:

The Merlin toolkit version 3.0.5, for Ocaml 4.06.0

As a matter of fact, prepending this var to running vim works. So looks that was the issue, not sure why and what would be the best way to deal with it.

[ArchangeGabriel]

Apparently this is because there is no ocaml-findlib on my system.