refactor: deprecate util.path.exists

Use `vim.uv.fs_stat` instead.

Work on neovim#2079.

.github/ci/run_sanitizer.sh

@@ -15,7 +15,7 @@ if git diff --pickaxe-all -U0 -G "${SEARCH_PATTERN}" "${REF_BRANCH}" "${PR_BRANC
   exit 1
 fi
 
-SEARCH_PATTERN='(util\.path\.dirname|util\.path\.sanitize)'
+SEARCH_PATTERN='(util\.path\.dirname|util\.path\.sanitize|util\.path\.exists)'
 
 if git diff --pickaxe-all -U0 -G "${SEARCH_PATTERN}" "${REF_BRANCH}" "${PR_BRANCH}" -- '*.lua' | grep -Ev '\.lua$' | grep -E "^\+.*${SEARCH_PATTERN}" ; then
   echo

lua/lspconfig/util.lua

@@ -102,23 +102,24 @@ M.path = (function()
     return path:gsub('([%[%]%?%*])', '\\%1')
   end
 
-  --- @param filename string
-  --- @return string|false
-  local function exists(filename)
-    local stat = uv.fs_stat(filename)
-    return stat and stat.type or false
-  end
-
   --- @param filename string
   --- @return boolean
   local function is_dir(filename)
-    return exists(filename) == 'directory'
+    local stat = uv.fs_stat(filename)
+    if not stat then
+      return false
+    end
+    return stat.type == 'directory'
   end
 
   --- @param filename string
   --- @return boolean
   local function is_file(filename)
-    return exists(filename) == 'file'
+    local stat = uv.fs_stat(filename)
+    if not stat then
+      return false
+    end
+    return stat.type == 'file'
   end
 
   --- @param path string
@@ -395,10 +396,18 @@ function M.strip_archive_subpath(path)
   return path
 end
 
----@deprecated use `vim.fs.dirname` instead
+--- @deprecated use `vim.fs.dirname` instead
 M.dirname = vim.fs.dirname
 
 --- @deprecated use `vim.fs.normalize` instead
 M.sanitize = vim.fs.normalize
 
+--- @deprecated use `vim.loop.fs_stat` instead
+--- @param filename string
+--- @return string|false
+function M.exists(filename)
+  local stat = uv.fs_stat(filename)
+  return stat and stat.type or false
+end
+
 return M