Add luacheck option to pass in more options

ale_linters/lua/luacheck.vim

@@ -4,12 +4,16 @@
 let g:ale_lua_luacheck_executable =
 \   get(g:, 'ale_lua_luacheck_executable', 'luacheck')
 
+let g:ale_lua_luacheck_options =
+\   get(g:, 'ale_lua_luacheck_options', '')
+
 function! ale_linters#lua#luacheck#GetExecutable(buffer) abort
     return ale#Var(a:buffer, 'lua_luacheck_executable')
 endfunction
 
 function! ale_linters#lua#luacheck#GetCommand(buffer) abort
     return ale_linters#lua#luacheck#GetExecutable(a:buffer)
+    \   . ' ' . ale#Var(a:buffer, 'lua_luacheck_options')
     \   . ' --formatter plain --codes --filename %s -'
 endfunction
 

doc/ale-lua.txt

@@ -13,5 +13,13 @@ g:ale_lua_luacheck_executable                   *g:ale_lua_luacheck_executable*
   This variable can be changed to change the path to luacheck.
 
 
+g:ale_lua_luacheck_options                         *g:ale_lua_luacheck_options*
+                                                   *b:ale_lua_luacheck_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be set to pass additional options to luacheck.
+
+
 -------------------------------------------------------------------------------
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:

test/command_callback/test_luacheck_command_callback.vader

@@ -0,0 +1,24 @@
+Before:
+  runtime ale_linters/lua/luacheck.vim
+
+After:
+  call ale#linter#Reset()
+  let g:ale_lua_luacheck_options = ''
+  let g:ale_lua_luacheck_executable = 'luacheck'
+
+Execute(The lua luacheck command callback should return the correct default string):
+  AssertEqual 'luacheck --formatter plain --codes --filename %s -',
+  \ join(split(ale_linters#lua#luacheck#GetCommand(1)))
+
+Execute(The lua luacheck command callback should let you set options):
+  let g:ale_lua_luacheck_options = '--config filename'
+
+  AssertEqual 'luacheck --config filename --formatter plain --codes --filename %s -',
+  \ join(split(ale_linters#lua#luacheck#GetCommand(1)))
+
+Execute(The luacheck executable should be configurable):
+  let g:ale_lua_luacheck_executable = 'luacheck.sh'
+
+  AssertEqual 'luacheck.sh', ale_linters#lua#luacheck#GetExecutable(1)
+  AssertEqual 'luacheck.sh --formatter plain --codes --filename %s -',
+  \ join(split(ale_linters#lua#luacheck#GetCommand(1)))