From 7cc96923c44bbcc541cbd211b6308d87a965f0c3 Mon Sep 17 00:00:00 2001
From: Bram Moolenaar <Bram@vim.org>
Date: Fri, 31 Jan 2020 22:41:38 +0100
Subject: [PATCH] patch 8.2.0189: cd() with NULL argument crashes

Problem:    cd() with NULL argument crashes.
Solution:   Check for NULL. (Ken Takata, closes #5558)
---
 src/ex_docmd.c          | 2 +-
 src/testdir/test_cd.vim | 2 ++
 src/version.c           | 2 ++
 3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 6df6975ea..80cc9307c 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -6572,7 +6572,7 @@ changedir_func(
     int		dir_differs;
     int		retval = FALSE;
 
-    if (allbuf_locked())
+    if (new_dir == NULL || allbuf_locked())
 	return FALSE;
 
     if (vim_strchr(p_cpo, CPO_CHDIR) != NULL && curbufIsChanged() && !forceit)
diff --git a/src/testdir/test_cd.vim b/src/testdir/test_cd.vim
index 05d3877c7..e44b25f0f 100644
--- a/src/testdir/test_cd.vim
+++ b/src/testdir/test_cd.vim
@@ -101,6 +101,8 @@ func Test_chdir_func()
   call assert_fails("call chdir('dir-abcd')", 'E472:')
   silent! let d = chdir("dir_abcd")
   call assert_equal("", d)
+  " Should not crash
+  call chdir(d)
 
   only | tabonly
   call chdir(topdir)
diff --git a/src/version.c b/src/version.c
index 9a3d42f0b..5f090c332 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    189,
 /**/
     188,
 /**/