Ignore files from homedir and root for indent

https://github.com/tpope/vim-sleuth/pull/57

plugin/polyglot.vim

@@ -36,7 +36,7 @@ function! s:guess(lines) abort
   let spaces_minus_tabs = 0
 
   for line in a:lines
-    if !len(line) || line =~# '^\s*$'
+    if !len(line) || line =~# '^\W*$'
       continue
     endif
 
@@ -138,6 +138,10 @@ function! s:detect_indent() abort
   let dir = expand('%:p:h')
   let level = 3
   while isdirectory(dir) && dir !=# fnamemodify(dir, ':h') && level > 0
+    " Ignore files from homedir and root 
+    if dir == expand('~') || dir == '/'
+      return
+    endif
     for neighbor in glob(dir . '/' . pattern, 0, 1)[0:level]
       " Do not consider directories above .git, .svn or .hg
       if fnamemodify(neighbor, ":h:t")[0] == "."
@@ -157,10 +161,6 @@ endfunction
 
 setglobal smarttab
 
-if !exists('g:did_indent_on')
-  filetype indent on
-endif
-
 augroup polyglot
   autocmd!
   autocmd FileType * call s:detect_indent()