Ansible lineinfile insertafter injects line at end of file

Question

I'm using lineinfile as follows:

lineinfile dest=./hosts_exp insertafter='\[hosts1\]' line="xxxxxxxxx" state=present

My hosts_exp is as follows:

[local]
localhost

[hosts1]

[hosts2]

[hosts3]

lineinfile inserts the text after [hosts3] instead of inserting it after [hosts1].

Answer 1

use:

lineinfile:
  dest: "./hosts_exp"
  line: "xxxxxxxxx"
  insertafter: '^\[hosts1\]'
  state: present