patch 9.0.0407: matchstr() does match column offset

Problem:    matchstr() does match column offset. (Yasuhiro Matsumoto)
Solution:   Accept line number zero. (closes #10938)
diff --git a/src/testdir/test_regexp_latin.vim b/src/testdir/test_regexp_latin.vim
index bc08439..6f3ffe2 100644
--- a/src/testdir/test_regexp_latin.vim
+++ b/src/testdir/test_regexp_latin.vim
@@ -30,11 +30,13 @@
 func Test_equivalence_re1()
   set re=1
   call s:equivalence_test()
+  set re=0
 endfunc
 
 func Test_equivalence_re2()
   set re=2
   call s:equivalence_test()
+  set re=0
 endfunc
 
 func Test_recursive_substitute()
@@ -67,6 +69,7 @@
     let actual = matchlist('abc def', '\(abc\>\)\?\s*\(def\)')
     call assert_equal(expected, actual)
   endfor
+  set re=0
 endfunc
 
 func Test_backref()
@@ -1141,4 +1144,14 @@
   prop_type_delete('name')
 enddef
 
+def Test_compare_column_matchstr()
+  enew
+  set re=1
+  call assert_equal('aaa', matchstr('aaaaaaaaaaaaaaaaaaaa', '.*\%<5v'))
+  set re=2
+  call assert_equal('aaa', matchstr('aaaaaaaaaaaaaaaaaaaa', '.*\%<5v'))
+  set re=0
+enddef
+
+
 " vim: shiftwidth=2 sts=2 expandtab