diff --git a/src/testdir/test_global.vim b/src/testdir/test_global.vim
index 34857b2..0f72c3c 100644
--- a/src/testdir/test_global.vim
+++ b/src/testdir/test_global.vim
@@ -116,7 +116,16 @@
   close!
 endfunc
 
-func Test_wrong_delimiter()
+" Test :g with ? as delimiter.
+func Test_global_question_delimiter()
+  new
+  call setline(1, ['aaaaa', 'b?bbb', 'ccccc', 'ddd?d', 'eeeee'])
+  g?\??delete
+  call assert_equal(['aaaaa', 'ccccc', 'eeeee'], getline(1, '$'))
+  bwipe!
+endfunc
+
+func Test_global_wrong_delimiter()
   call assert_fails('g x^bxd', 'E146:')
 endfunc
 
diff --git a/src/testdir/test_substitute.vim b/src/testdir/test_substitute.vim
index a2367cd..afdc104 100644
--- a/src/testdir/test_substitute.vim
+++ b/src/testdir/test_substitute.vim
@@ -174,8 +174,8 @@
   bwipe!
 endfunc
 
-" Test :s with ? as separator.
-func Test_substitute_question_separator()
+" Test :s with ? as delimiter.
+func Test_substitute_question_delimiter()
   new
   call setline(1, '??:??')
   %s?\?\??!!?g