Remove the need for pointless callbacks for LSP linters

1 files changed, 8 insertions, 5 deletions

diff --git a/autoload/ale/linter.vim b/autoload/ale/linter.vim
index 3419f5af..4138b876 100644
--- a/autoload/ale/linter.vim
+++ b/autoload/ale/linter.vim
@@ -52,21 +52,24 @@ function! ale#linter#PreProcess(linter) abort
     let l:obj = {
     \   'name': get(a:linter, 'name'),
     \   'lsp': get(a:linter, 'lsp', ''),
-    \   'callback': get(a:linter, 'callback'),
     \}
 
     if type(l:obj.name) != type('')
         throw '`name` must be defined to name the linter'
     endif
 
-    if !s:IsCallback(l:obj.callback)
-        throw '`callback` must be defined with a callback to accept output'
-    endif
-
     let l:needs_address = l:obj.lsp ==# 'socket'
     let l:needs_executable = l:obj.lsp !=# 'socket'
     let l:needs_command = l:obj.lsp !=# 'socket'
 
+    if empty(l:obj.lsp)
+        let l:obj.callback = get(a:linter, 'callback')
+
+        if !s:IsCallback(l:obj.callback)
+            throw '`callback` must be defined with a callback to accept output'
+        endif
+    endif
+
     if index(['', 'socket', 'stdio', 'tsserver'], l:obj.lsp) < 0
         throw '`lsp` must be either `''lsp''` or `''tsserver''` if defined'
     endif