Fix #1176 - Add an option for caching failing executable checks

1 files changed, 11 insertions, 7 deletions

diff --git a/autoload/ale/engine.vim b/autoload/ale/engine.vim
index 811b2438..150b53c1 100644
--- a/autoload/ale/engine.vim
+++ b/autoload/ale/engine.vim
@@ -32,16 +32,20 @@ function! ale#engine#IsExecutable(buffer, executable) abort
         return 0
     endif
 
-    if has_key(s:executable_cache_map, a:executable)
-        return 1
-    endif
+    " Check for a cached executable() check.
+    let l:result = get(s:executable_cache_map, a:executable, v:null)
 
-    let l:result = 0
+    if l:result isnot v:null
+        return l:result
+    endif
 
-    if executable(a:executable)
-        let s:executable_cache_map[a:executable] = 1
+    " Check if the file is executable, and convert -1 to 1.
+    let l:result = executable(a:executable) isnot 0
 
-        let l:result = 1
+    " Cache the executable check if we found it, or if the option to cache
+    " failing checks is on.
+    if l:result || g:ale_cache_executable_check_failures
+        let s:executable_cache_map[a:executable] = l:result
     endif
 
     if g:ale_history_enabled