# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1599398104 -7200
# Node ID 3ec9e302ec940b355cf074a5d72b14a7bc5c5b65
# Parent  572e3d7849e5a15346e53edec5fdb38603badbbf
patch 8.2.1621: crash when using submatch(0, 1) in substitute()

Commit: https://github.com/vim/vim/commit/8a0dcf43305586853f452a77fa295b0c8d54b463
Author: Bram Moolenaar <Bram@vim.org>
Date:   Sun Sep 6 15:14:45 2020 +0200

    patch 8.2.1621: crash when using submatch(0, 1) in substitute()

    Problem:    Crash when using submatch(0, 1) in substitute().
    Solution:   Increment reference count. (closes https://github.com/vim/vim/issues/6887)

diff --git a/src/regexp.c b/src/regexp.c
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -2543,6 +2543,7 @@ reg_submatch_list(int no)
 	list_free(list);
 	return NULL;
     }
+    ++list->lv_refcount;
     return list;
 }
 #endif
diff --git a/src/testdir/test_substitute.vim b/src/testdir/test_substitute.vim
--- a/src/testdir/test_substitute.vim
+++ b/src/testdir/test_substitute.vim
@@ -881,6 +881,12 @@ func Test_invalid_submatch()
   call assert_equal([], submatch(1, 1))
 endfunc
 
+func Test_submatch_list_concatenate()
+  let pat = 'A\(.\)'
+  let Rep = {-> string([submatch(0, 1)] + [[submatch(1)]])}
+  call substitute('A1', pat, Rep, '')->assert_equal("[['A1'], ['1']]")
+endfunc
+
 func Test_substitute_expr_arg()
   call assert_equal('123456789-123456789=', substitute('123456789',
 	\ '\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)\(.\)',
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1621,
+/**/
     1620,
 /**/
     1619,