patch 7.4.2269
Problem:    Using 'hlsearch' highlighting instead of matchpos if there is no
            search match.
Solution:   Pass NULL as last item to next_search_hl() when searching for
            'hlsearch' match. (Shane Harper, closes #1013)
diff --git a/src/testdir/test_match.vim b/src/testdir/test_match.vim
index 0008936..9ac1db1 100644
--- a/src/testdir/test_match.vim
+++ b/src/testdir/test_match.vim
@@ -186,4 +186,31 @@
   set hlsearch&
 endfunc
 
+func Test_matchaddpos_using_negative_priority()
+  set hlsearch
+
+  call clearmatches()
+
+  call setline(1, 'x')
+  let @/='x'
+  redraw!
+  let search_attr = screenattr(1,1)
+
+  let @/=''
+  call matchaddpos('Error', [1], 10)
+  redraw!
+  let error_attr = screenattr(1,1)
+
+  call setline(2, '-1 match priority')
+  call matchaddpos('Error', [2], -1)
+  redraw!
+  let negative_match_priority_attr = screenattr(2,1)
+
+  call assert_notequal(negative_match_priority_attr, search_attr, "Match with negative priority is incorrectly highlighted with Search highlight.")
+  call assert_equal(negative_match_priority_attr, error_attr)
+
+  nohl
+  set hlsearch&
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab