Merge 329a6d82cb into 7121983c45

runtime/lua/vim/loader.lua

@@ -120,12 +120,22 @@ local function cache_filename(name)
   return ret:sub(-4) == '.lua' and (ret .. 'c') or (ret .. '.luac')
 end
 
+local writing = {} --- @type table<string,function>
+
 --- Saves the cache entry for a given module or file
 --- @param cname string cache filename
 --- @param hash vim.loader.CacheHash
 --- @param chunk function
 local function write_cachefile(cname, hash, chunk)
-  local f = assert(uv.fs_open(cname, 'w', 438))
+  if writing[cname] then
+    return
+  end
+
+  writing[cname] = chunk
+  uv.fs_open(cname, 'w', 438, function(err, f)
+    if err then
+      error(err)
+    end
     local header = {
       VERSION,
       hash.size,
@@ -135,6 +145,8 @@ local function write_cachefile(cname, hash, chunk)
     uv.fs_write(f, table.concat(header, ',') .. '\0')
     uv.fs_write(f, string.dump(chunk))
     uv.fs_close(f)
+    writing[cname] = nil
+  end)
 end
 
 --- @param path string
@@ -255,6 +267,10 @@ local function loadfile_cached(filename, mode, env)
     end
   end
 
+  if writing[cname] then
+    return writing[cname]
+  end
+
   local chunk, err = _loadfile(modpath, mode, env)
   if chunk and stat then
     write_cachefile(cname, stat, chunk)