patch 8.1.2133: some tests fail when run as root

Problem:    Some tests fail when run as root.
Solution:   Add CheckNotRoot and use it. (James McCoy, closes #5020)

src/testdir/check.vim

@@ -1,3 +1,5 @@
+source shared.vim
+
 " Command to check for the presence of a feature.
 command -nargs=1 CheckFeature call CheckFeature(<f-args>)
 func CheckFeature(name)
@@ -102,3 +104,11 @@ func CheckNotGui()
     throw 'Skipped: only works in the terminal'
   endif
 endfunc
+
+" Command to check that test is not running as root
+command CheckNotRoot call CheckNotRoot()
+func CheckNotRoot()
+  if IsRoot()
+    throw 'Skipped: cannot run test as root'
+  endif
+endfunc

src/testdir/shared.vim

@@ -325,3 +325,12 @@ func RunVimPiped(before, after, arguments, pipecmd)
   endif
   return 1
 endfunc
+
+func IsRoot()
+  if !has('unix')
+    return v:false
+  elseif $USER == 'root' || system('id -un') =~ '\<root\>'
+    return v:true
+  endif
+  return v:false
+endfunc

src/testdir/test_rename.vim

@@ -1,5 +1,7 @@
 " Test rename()
 
+source shared.vim
+
 func Test_rename_file_to_file()
   call writefile(['foo'], 'Xrename1')
 
@@ -81,7 +83,7 @@ func Test_rename_copy()
 
   call assert_equal(0, rename('Xrenamedir/Xrenamefile', 'Xrenamefile'))
 
-  if !has('win32')
+  if !has('win32') && !IsRoot()
     " On Windows, the source file is removed despite
     " its directory being made not writable.
     call assert_equal(['foo'], readfile('Xrenamedir/Xrenamefile'))

src/testdir/test_swap.vim

@@ -1,5 +1,7 @@
 " Tests for the swap feature
 
+source shared.vim
+
 func s:swapname()
   return trim(execute('swapname'))
 endfunc
@@ -196,6 +198,8 @@ func Test_swapfile_delete()
   quit
   call assert_equal(fnamemodify(swapfile_name, ':t'), fnamemodify(s:swapname, ':t'))
 
+  " This test won't work as root because root can successfully run kill(1, 0)
+  if !IsRoot()
     " Write the swapfile with a modified PID, now it will be automatically
     " deleted. Process one should never be Vim.
     let swapfile_bytes[24:27] = 0z01000000
@@ -204,6 +208,7 @@ func Test_swapfile_delete()
     split XswapfileText
     quit
     call assert_equal('', s:swapname)
+  endif
 
   " Now set the modified flag, the swap file will not be deleted
   let swapfile_bytes[28 + 80 + 899] = 0x55

src/testdir/test_terminal.vim

@@ -570,7 +570,7 @@ func Test_terminal_cwd_failure()
 
   " Case 3: Directory exists but is not accessible.
   " Skip this for root, it will be accessible anyway.
-  if $USER != 'root'
+  if !IsRoot()
     call mkdir('XdirNoAccess', '', '0600')
     " return early if the directory permissions could not be set properly
     if getfperm('XdirNoAccess')[2] == 'x'
@@ -1353,7 +1353,6 @@ endfunc
 func Test_terminal_api_call()
   CheckRunVimInTerminal
 
-call ch_logfile('logfile', 'w')
   unlet! g:called_bufnum
   unlet! g:called_arg
 

src/testdir/test_viminfo.vim

@@ -736,6 +736,7 @@ endfunc
 " Test for an unwritable and unreadble 'viminfo' file
 func Test_viminfo_perm()
   CheckUnix
+  CheckNotRoot
   call writefile([''], 'Xviminfo')
   call setfperm('Xviminfo', 'r-x------')
   call assert_fails('wviminfo Xviminfo', 'E137:')

src/version.c

@@ -753,6 +753,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2133,
 /**/
     2132,
 /**/