patch 9.1.0721: tests: test_mksession does not consider XDG_CONFIG_HOME

Problem:  tests: test_mksession does not consider XDG_CONFIG_HOME
Solution: allow to match $HOME/.vim/ and $HOME/.config/vim for &viewdir
          (John M Devin)

closes: #15639

Signed-off-by: John M Devin <john.m.devin@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/testdir/setup.vim

@@ -34,6 +34,10 @@ if 1
   " defaults before we get here, and test_mksession checks that.
   let $ORIGHOME = $HOME
 
+  if !exists('$XDG_CONFIG_HOME')
+    let $XDG_CONFIG_HOME = $HOME .. '/.config'
+  endif
+
   " Make sure $HOME does not get read or written.
   " It must exist, gnome tries to create $HOME/.gnome2
   let $HOME = getcwd() . '/XfakeHOME'

src/testdir/test_mksession.vim

@@ -1270,7 +1270,10 @@ func Test_mkview_default_home()
     " use escape() to handle backslash path separators
     call assert_match('^' .. escape($ORIGHOME, '\') .. '/vimfiles', &viewdir)
   elseif has('unix')
-    call assert_match('^' .. $ORIGHOME .. '/.vim', &viewdir)
+    call assert_match(
+          \ '^' .. $ORIGHOME .. '/.vim\|' ..
+          \ '^' .. $XDG_CONFIG_HOME .. '/vim'
+          \ , &viewdir)
   elseif has('amiga')
     call assert_match('^home:vimfiles', &viewdir)
   elseif has('mac')

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    721,
 /**/
     720,
 /**/