feat(fs): add vim.fs.dirname()

runtime/doc/lua.txt

@@ -2151,6 +2151,15 @@ set({mode}, {lhs}, {rhs}, {opts})                           *vim.keymap.set()*
 ==============================================================================
 Lua module: fs                                                        *lua-fs*
 
+dirname({file})                                             *vim.fs.dirname()*
+                Return the parent directory of the given file or directory
+
+                Parameters: ~
+                    {file}  (string) File or directory
+
+                Return: ~
+                    (string) Parent directory of {file}
+
 parents({start})                                            *vim.fs.parents()*
                 Iterate over all the parents of the given file or directory.
 

runtime/lua/vim/fs.lua

@@ -21,7 +21,7 @@ local M = {}
 ---@return (function) Iterator
 function M.parents(start)
   return function(_, dir)
-    local parent = vim.fn.fnamemodify(dir, ":h")
+    local parent = M.dirname(dir)
     if parent == dir then
       return nil
     end
@@ -32,4 +32,12 @@ function M.parents(start)
     start
 end
 
+--- Return the parent directory of the given file or directory
+---
+---@param file (string) File or directory
+---@return (string) Parent directory of {file}
+function M.dirname(file)
+  return vim.fn.fnamemodify(file, ':h')
+end
+
 return M

test/functional/lua/fs_spec.lua

@@ -30,4 +30,13 @@ describe('vim.fs', function()
       rmdir(test_dir)
     end)
   end)
+
+  describe('dirname()', function()
+    it('works', function()
+      eq(test_build_dir, exec_lua([[
+        local nvim_dir = ...
+        return vim.fs.dirname(nvim_dir)
+      ]], nvim_dir))
+    end)
+  end)
 end)