Fix lua repl && add layer doc

autoload/SpaceVim/layers/lang/lua.vim

@@ -11,30 +11,40 @@
 " <
 
 function! SpaceVim#layers#lang#lua#plugins() abort
-    let plugins = []
-    " Improved Lua 5.3 syntax and indentation support for Vim
-    call add(plugins, ['tbastos/vim-lua', {'on_ft' : 'lua'}])
-    call add(plugins, ['WolfgangMehner/lua-support', {'on_ft' : 'lua'}])
-    call add(plugins, ['SpaceVim/vim-luacomplete', {'on_ft' : 'lua', 'if' : has('lua')}])
-    return plugins
+  let plugins = []
+  " Improved Lua 5.3 syntax and indentation support for Vim
+  call add(plugins, ['tbastos/vim-lua', {'on_ft' : 'lua'}])
+  call add(plugins, ['WolfgangMehner/lua-support', {'on_ft' : 'lua'}])
+  call add(plugins, ['SpaceVim/vim-luacomplete', {'on_ft' : 'lua', 'if' : has('lua')}])
+  return plugins
 endfunction
 
+let s:lua_repl_command = ''
+
 function! SpaceVim#layers#lang#lua#config() abort
   if has('lua')
     augroup spacevim_lua
-        autocmd FileType lua setlocal omnifunc=luacomplete#complete
+      autocmd FileType lua setlocal omnifunc=luacomplete#complete
     augroup END
   endif
 
   call SpaceVim#mapping#space#regesit_lang_mappings('lua', funcref('s:language_specified_mappings'))
   call SpaceVim#plugins#runner#reg_runner('lua', 'lua %s')
-  if executable('luap')
-    call SpaceVim#plugins#repl#reg('lua', 'luap')
+  if !empty(s:lua_repl_command)
+      call SpaceVim#plugins#repl#reg('lua',s:lua_repl_command)
   else
-    call SpaceVim#plugins#repl#reg('lua', 'lua')
+    if executable('luap')
+      call SpaceVim#plugins#repl#reg('lua', 'luap')
+    else
+      call SpaceVim#plugins#repl#reg('lua', 'lua')
+    endif
   endif
 endfunction
 
+function! SpaceVim#layers#lang#lua#set_variablee(opt) abort
+  let s:lua_repl_command = get(a:opt, 'repl_command', '') 
+endfunction
+
 " Add language specific mappings
 function! s:language_specified_mappings() abort
   call SpaceVim#mapping#space#langSPC('nmap', ['l','b'], 'LuaCompile', 'lua compile', 1)

docs/layers/lang/lua.md

@@ -0,0 +1,57 @@
+---
+title: "SpaceVim lang#lua layer"
+description: "This layer is for lua development, provide autocompletion, syntax checking, code format for lua file."
+---
+
+# [SpaceVim Layers:](https://spacevim.org/layers) lang#lua
+
+<!-- vim-markdown-toc GFM -->
+
+- [Description](#description)
+- [Installation](#installation)
+  - [Layer](#layer)
+  - [Syntax checking && Code formatting](#syntax-checking--code-formatting)
+- [Key bindings](#key-bindings)
+  - [Inferior REPL process](#inferior-repl-process)
+  - [Running current script](#running-current-script)
+
+<!-- vim-markdown-toc -->
+
+## Description
+
+This layer is for lua development.
+
+## Installation
+
+### Layer
+
+To use this configuration layer, add `SPLayer 'lang#lua'` to your custom configuration file.
+
+### Syntax checking && Code formatting
+
+
+## Key bindings
+
+### Inferior REPL process
+
+Start a `lua` or `luap` inferior REPL process with `SPC l s i`.  You may change the REPL command by layer option `repl_command`. for example, if you want to use `lua.repl`, load this layer via:
+
+```vim
+call SpaceVim#layers#load('lang#lua'
+    \ {
+    \ 'repl_command' : '~/.luarocks/lib/luarocks/rocks-5.3/luarepl/0.8-1/bin/rep.lua',
+    \ }
+```
+
+Send code to inferior process commands:
+
+| Key Binding | Description                                      |
+| ----------- | ------------------------------------------------ |
+| `SPC l s b` | send buffer and keep code buffer focused         |
+| `SPC l s l` | send line and keep code buffer focused           |
+| `SPC l s s` | send selection text and keep code buffer focused |
+
+
+### Running current script
+
+To running a ruby script, you can press `SPC l r` to run current file without loss focus, and the result will be shown in a runner buffer.