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

runtime/doc/lua.txt

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

runtime/lua/vim/fs.lua

@@ -40,4 +40,12 @@ function M.dirname(file)
   return vim.fn.fnamemodify(file, ':h')
 end
 
+--- Return the basename of the given file or directory
+---
+---@param file (string) File or directory
+---@return (string) Basename of {file}
+function M.basename(file)
+  return vim.fn.fnamemodify(file, ':t')
+end
+
 return M

test/functional/lua/fs_spec.lua

@@ -7,6 +7,10 @@ local mkdir_p = helpers.mkdir_p
 local rmdir = helpers.rmdir
 local nvim_dir = helpers.nvim_dir
 local test_build_dir = helpers.test_build_dir
+local iswin = helpers.iswin
+local nvim_prog = helpers.nvim_prog
+
+local nvim_prog_basename = iswin() and 'nvim.exe' or 'nvim'
 
 before_each(clear)
 
@@ -39,4 +43,13 @@ describe('vim.fs', function()
       ]], nvim_dir))
     end)
   end)
+
+  describe('basename()', function()
+    it('works', function()
+      eq(nvim_prog_basename, exec_lua([[
+        local nvim_prog = ...
+        return vim.fs.basename(nvim_prog)
+      ]], nvim_prog))
+    end)
+  end)
 end)