# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1660510804 -7200
# Node ID 1e9ee1b61d6dc8c3bdf46ea079fd4de7c94e081c
# Parent  806c3ef643fe377ba74c61a24504bc3ee914c3a9
patch 9.0.0212: invalid memory access when compiling :unlet

Commit: https://github.com/vim/vim/commit/dbdd16b62560413abcc3c8e893cc3010ccf31666
Author: Bram Moolenaar <Bram@vim.org>
Date:   Sun Aug 14 21:46:07 2022 +0100

    patch 9.0.0212: invalid memory access when compiling :unlet

    Problem:    Invalid memory access when compiling :unlet.
    Solution:   Don't read past the end of the line.

diff --git a/src/testdir/test_vim9_cmd.vim b/src/testdir/test_vim9_cmd.vim
--- a/src/testdir/test_vim9_cmd.vim
+++ b/src/testdir/test_vim9_cmd.vim
@@ -1740,12 +1740,19 @@ def Test_lockvar()
 
   lines =<< trim END
       def _()
-        s:0([], s:0)
         lockv
       enddef
       defcomp
   END
-  v9.CheckScriptFailure(lines, 'E179', 2)
+  v9.CheckScriptFailure(lines, 'E179', 1)
+
+  lines =<< trim END
+      def T()
+        unlet
+      enddef
+      defcomp
+  END
+  v9.CheckScriptFailure(lines, 'E179', 1)
 enddef
 
 def Test_substitute_expr()
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -736,6 +736,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    212,
+/**/
     211,
 /**/
     210,
diff --git a/src/vim9cmds.c b/src/vim9cmds.c
--- a/src/vim9cmds.c
+++ b/src/vim9cmds.c
@@ -92,6 +92,12 @@ free_locals(cctx_T *cctx)
     int
 check_vim9_unlet(char_u *name)
 {
+    if (*name == NUL)
+    {
+	semsg(_(e_argument_required_for_str), "unlet");
+	return FAIL;
+    }
+
     if (name[1] != ':' || vim_strchr((char_u *)"gwtb", *name) == NULL)
     {
 	// "unlet s:var" is allowed in legacy script.