Convince grep to output all lines, not just those with matches

Say I have the following file:

$ cat test



test line 1

test line 2

line without the search word

another line without it

test line 3 with two test words

test line 4

By default, grep returns each line that contains the search term:

$ grep test test



test line 1

test line 2

test line 3 with two test words

test line 4

My current terrible hack to accomplish this (at least on files that don't have 10000+ consecutive lines with no matches) is:

$ grep -B 9999 -A 9999 test test

If grep can't accomplish this, is there another command-line tool that offers the same functionality? I've fiddled with ack, but it doesn't seem to have an option for it either