t/7000-mseq.t: add test for 74857db19

t/7000-mseq.t

@@ -1,7 +1,7 @@
 #!/bin/sh -e
 cd ${0%/*}
 . ./lib.sh
-plan 10
+plan 11
 
 rm -rf test.dir
 mkdir test.dir
@@ -31,6 +31,7 @@ check_test 'whole thread' -eq 4 'mseq 6= | wc -l'
 check_test  'subthread' -eq 2 'mseq 7_ | wc -l'
 check 'parent' 'mseq 6^ | grep "inbox/cur/5_1:2,"'
 check_test 'range' -eq 3 'mseq 1:3 | wc -l'
+check_same 'multiple mmsg' 'mseq 1 2' 'echo "inbox/cur/1:2,\ninbox/cur/2:2,"'
 
 cat <<! >seq
 inbox/cur/1:2,