refactor: rewrite perl provider in lua

runtime/autoload/provider/perl.vim

@@ -1,83 +1,15 @@
-if exists('s:loaded_perl_provider')
+if exists('g:loaded_perl_provider')
   finish
 endif
 
-let s:loaded_perl_provider = 1
-
-function! provider#perl#Detect() abort
-  " use g:perl_host_prog if set or check if perl is on the path
-  let prog = exepath(get(g:, 'perl_host_prog', 'perl'))
-  if empty(prog)
-    return ['', '']
-  endif
-
-  " if perl is available, make sure we have 5.22+
-  call system([prog, '-e', 'use v5.22'])
-  if v:shell_error
-    return ['', 'Perl version is too old, 5.22+ required']
-  endif
-
-  " if perl is available, make sure the required module is available
-  call system([prog, '-W', '-MNeovim::Ext', '-e', ''])
-  if v:shell_error
-    return ['', '"Neovim::Ext" cpan module is not installed']
-  endif
-
-  return [prog, '']
-endfunction
-
-function! provider#perl#Prog() abort
-  return s:prog
+function! provider#perl#Call(method, args) abort
+  return v:lua.require'vim.provider.perl'.call(a:method, a:args)
 endfunction
 
 function! provider#perl#Require(host) abort
-  if s:err != ''
-    echoerr s:err
-    return
-  endif
-
-  let prog = provider#perl#Prog()
-  let args = [s:prog, '-e', 'use Neovim::Ext; start_host();']
-
-  " Collect registered perl plugins into args
-  let perl_plugins = remote#host#PluginsForHost(a:host.name)
-  for plugin in perl_plugins
-    call add(args, plugin.path)
-  endfor
-
-  return provider#Poll(args, a:host.orig_name, '$NVIM_PERL_LOG_FILE')
+  return v:lua.require'vim.provider.perl'.require(a:host, s:prog)
 endfunction
 
-function! provider#perl#Call(method, args) abort
-  if s:err != ''
-    echoerr s:err
-    return
-  endif
-
-  if !exists('s:host')
-    try
-      let s:host = remote#host#Require('legacy-perl-provider')
-    catch
-      let s:err = v:exception
-      echohl WarningMsg
-      echomsg v:exception
-      echohl None
-      return
-    endtry
-  endif
-  return call('rpcrequest', insert(insert(a:args, 'perl_'.a:method), s:host))
-endfunction
-
-let [s:prog, s:err] = provider#perl#Detect()
+let s:prog = v:lua.require'vim.provider.perl'.detect()
 let g:loaded_perl_provider = empty(s:prog) ? 1 : 2
-
-if g:loaded_perl_provider != 2
-  let s:err = 'Cannot find perl or the required perl module'
-endif
-
-
-" The perl provider plugin will run in a separate instance of the perl
-" host.
-call remote#host#RegisterClone('legacy-perl-provider', 'perl')
-call remote#host#RegisterPlugin('legacy-perl-provider', 'ScriptHost.pm', [])
-
+call v:lua.require'vim.provider.perl'.start()

runtime/lua/provider/perl/health.lua

@@ -9,19 +9,14 @@ function M.check()
     return
   end
 
-  local perl_detect_table = vim.fn['provider#perl#Detect']()
-  local perl_exec = perl_detect_table[1]
-  local perl_warnings = perl_detect_table[2]
+  local perl_exec, perl_warnings = require('vim.provider.perl').detect()
 
-  if perl_exec:find('^%s*$') then
-    if perl_warnings:find('%S') then
-      health.warn(perl_warnings, {
+  if not perl_exec then
+    health.warn(assert(perl_warnings), {
       'See :help provider-perl for more information.',
       'You may disable this provider (and warning) by adding `let g:loaded_perl_provider = 0` to your init.vim',
     })
-    else
     health.warn('No usable perl executable found')
-    end
     return
   end
 

runtime/lua/vim/provider/perl.lua

@@ -0,0 +1,66 @@
+local M = {}
+local s_err ---@type string?
+local s_host ---@type string?
+
+function M.require(host, prog)
+  local args = { prog, '-e', 'use Neovim::Ext; start_host();' }
+
+  -- Collect registered perl plugins into args
+  local perl_plugins = vim.fn['remote#host#PluginsForHost'](host.name) ---@type any
+  ---@param plugin any
+  for _, plugin in ipairs(perl_plugins) do
+    table.insert(args, plugin.path)
+  end
+
+  return vim.fn['provider#Poll'](args, host.orig_name, '$NVIM_PERL_LOG_FILE')
+end
+
+--- @return string? path to detected perl, if any; nil if not found
+--- @return string? error message if perl can't be detected; nil if success
+function M.detect()
+  -- use g:perl_host_prog if set or check if perl is on the path
+  local prog = vim.fn.exepath(vim.g.perl_host_prog or 'perl')
+  if prog == '' then
+    return nil, 'No perl executable found'
+  end
+
+  -- if perl is available, make sure we have 5.22+
+  vim.fn.system({ prog, '-e', 'use v5.22' })
+  if vim.v.shell_error ~= 0 then
+    return nil, 'Perl version is too old, 5.22+ required'
+  end
+
+  -- if perl is available, make sure the required module is available
+  vim.fn.system({ prog, '-W', '-MNeovim::Ext', '-e', '' })
+  if vim.v.shell_error ~= 0 then
+    return nil, '"Neovim::Ext" cpan module is not installed'
+  end
+  return prog, nil
+end
+
+function M.call(method, args)
+  if s_err then
+    return
+  end
+
+  if not s_host then
+    -- Ensure that we can load the Perl host before bootstrapping
+    local ok, result = pcall(vim.fn['remote#host#Require'], 'legacy-perl-provider') ---@type any, any
+    if not ok then
+      s_err = result
+      vim.api.nvim_echo({ result, 'WarningMsg' }, true, {})
+      return
+    end
+    s_host = result
+  end
+
+  return vim.fn.rpcrequest(s_host, 'perl_' .. method, unpack(args))
+end
+
+function M.start()
+  -- The perl provider plugin will run in a separate instance of the perl host.
+  vim.fn['remote#host#RegisterClone']('legacy-perl-provider', 'perl')
+  vim.fn['remote#host#RegisterPlugin']('legacy-perl-provider', 'ScriptHost.pm', {})
+end
+
+return M

test/functional/helpers.lua

@@ -936,10 +936,17 @@ end
 --- @param provider string
 --- @return string|boolean?
 function module.missing_provider(provider)
-  if provider == 'ruby' or provider == 'node' or provider == 'perl' then
+  if provider == 'ruby' then
     --- @type string?
-    local e = module.fn['provider#' .. provider .. '#Detect']()[2]
+    local e = module.fn['provider#ruby#Detect']()[2]
     return e ~= '' and e or false
+  elseif provider == 'node' then
+    --- @type string?
+    local e = module.fn['provider#node#Detect']()[2]
+    return e ~= '' and e or false
+  elseif provider == 'perl' then
+    --- @type string?
+    return module.exec_lua([[return {require('vim.provider.perl').detect()}]])[2]
   elseif provider == 'python' then
     return module.exec_lua([[return {require('vim.provider.python').detect_by_module('neovim')}]])[2]
   end