ansible/ansible — pull request #2482 by bladypirat (2013-03-22 10:53:58+00:00)
Title: disabled appending file with garbage when regexp didn't match.

When using lineinfile module, lines was appended with garbage when regular expression didn't match.
Using example: lineinfile dest=/tmp/grub.conf state=present regexp='^(splashimage=.*)$' line="#\\1"
when regexp was not found originally lineinfile module would append file with "#\1".
I believe better is do nothing if regexp returned false.