add support for locally installed coffee

ale_linters/coffee/coffee.vim

@@ -1,10 +1,23 @@
 " Author: KabbAmine - https://github.com/KabbAmine
 " Description: Coffee for checking coffee files
 
+function! ale_linters#coffee#coffee#GetExecutable(buffer) abort
+    return ale#util#ResolveLocalPath(
+    \   a:buffer,
+    \   'node_modules/.bin/coffee',
+    \   'coffee'
+    \)
+endfunction
+
+function! ale_linters#coffee#coffee#GetCommand(buffer) abort
+    return ale_linters#coffee#coffee#GetExecutable(a:buffer)
+    \   . ' -cp -s'
+endfunction
+
 call ale#linter#Define('coffee', {
 \   'name': 'coffee',
-\   'executable': 'coffee',
-\   'command': 'coffee -cp -s',
+\   'executable_callback': 'ale_linters#coffee#coffee#GetExecutable',
+\   'command_callback': 'ale_linters#coffee#coffee#GetCommand',
 \   'output_stream': 'stderr',
 \   'callback': 'ale#handlers#HandleGCCFormat',
 \})