refactor: rewrite ruby provider in lua

runtime/lua/vim/provider/ruby.lua

@@ -0,0 +1,61 @@
+local M = {}
+local s_err ---@type string?
+local s_host ---@type string?
+
+function M.require(host)
+  local prog = M.detect()
+  local args = { prog }
+  local ruby_plugins = vim.fn['remote#host#PluginsForHost'](host.name) ---@type any
+
+  ---@param plugin any
+  for _, plugin in ipairs(ruby_plugins) do
+    table.insert(args, plugin.path)
+  end
+
+  return vim.fn['provider#Poll'](args, host.orig_name, '$NVIM_RUBY_LOG_FILE')
+end
+
+function M.call(method, args)
+  if s_err then
+    return
+  end
+
+  if not s_host then
+    local ok, result = pcall(vim.fn['remote#host#Require'], 'legacy-ruby-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, 'ruby_' .. method, unpack(args))
+end
+
+function M.detect()
+  local prog ---@type string
+  if vim.g.ruby_host_prog then
+    prog = vim.fn.expand(vim.g.ruby_host_prog, true)
+  elseif vim.fn.has('win32') == 1 then
+    prog = vim.fn.exepath('neovim-ruby-host.bat')
+  else
+    local p = vim.fn.exepath('neovim-ruby-host')
+    if p == '' then
+      prog = ''
+    else
+      -- neovim-ruby-host could be an rbenv shim for another Ruby version.
+      vim.fn.system(p)
+      prog = vim.v.shell_error ~= 0 and '' or p
+    end
+  end
+  local err = prog == '' and 'missing ruby or ruby-host' or ''
+  return prog, err
+end
+
+function M.start(plugin_path)
+  vim.fn['remote#host#RegisterClone']('legacy-ruby-provider', 'ruby')
+  vim.fn['remote#host#RegisterPlugin']('legacy-ruby-provider', plugin_path, {})
+end
+
+return M