Fix #371 Allow ALE to be disabled in different buffers

autoload/ale.vim

@@ -29,6 +29,11 @@ function! ale#Queue(delay, ...) abort
         throw "linting_flag must be either '' or 'lint_file'"
     endif
 
+    " Stop here if ALE is disabled.
+    if !ale#Var(bufnr(''), 'enabled')
+        return
+    endif
+
     if ale#ShouldDoNothing()
         return
     endif

autoload/ale/cursor.vim

@@ -66,6 +66,15 @@ function! s:StopCursorTimer() abort
 endfunction
 
 function! ale#cursor#EchoCursorWarning(...) abort
+    " Stop here if ALE is disabled.
+    if !ale#Var(bufnr(''), 'enabled')
+        return
+    endif
+
+    if ale#ShouldDoNothing()
+        return
+    endif
+
     " Only echo the warnings in normal mode, otherwise we will get problems.
     if mode() !=# 'n'
         return
@@ -89,6 +98,11 @@ let s:cursor_timer = -1
 let s:last_pos = [0, 0, 0]
 
 function! ale#cursor#EchoCursorWarningWithDelay() abort
+    " Stop here if ALE is disabled.
+    if !ale#Var(bufnr(''), 'enabled')
+        return
+    endif
+
     if ale#ShouldDoNothing()
         return
     endif