Add bundle option to mdl

ale_linters/markdown/mdl.vim

@@ -10,9 +10,13 @@ endfunction
 
 function! ale_linters#markdown#mdl#GetCommand(buffer) abort
     let l:executable = ale_linters#markdown#mdl#GetExecutable(a:buffer)
+    let l:exec_args = l:executable =~? 'bundle$'
+    \   ? ' exec mdl'
+    \   : ''
+
     let l:options = ale#Var(a:buffer, 'markdown_mdl_options')
 
-    return ale#Escape(l:executable)
+    return ale#Escape(l:executable) . l:exec_args
     \   . (!empty(l:options) ? ' ' . l:options : '')
 endfunction
 

doc/ale-markdown.txt

@@ -10,7 +10,8 @@ g:ale_markdown_mdl_executable                   *g:ale_markdown_mdl_executable*
   Type: |String|
   Default: `'mdl'`
 
-  See |ale-integrations-local-executables|
+  Override the invoked mdl binary. This is useful for running mdl from
+  binstubs or a bundle.
 
 
 g:ale_markdown_mdl_options                         *g:ale_markdown_mdl_options*

test/command_callback/test_markdown_mdl_command_callback.vader

@@ -26,3 +26,10 @@ Execute(The executable and options should be configurable):
   AssertEqual
   \ ale_linters#markdown#mdl#GetCommand(bufnr('')),
   \ ale#Escape('foo bar') . ' --wat'
+
+Execute(Setting bundle appends 'exec mdl'):
+  let g:ale_markdown_mdl_executable = 'path to/bundle'
+
+  AssertEqual
+  \ ale#Escape('path to/bundle') . ' exec mdl',
+  \ ale_linters#markdown#mdl#GetCommand(bufnr(''))