Ansibleで「~/」を指定した際に指し示す場所

結論から言うと、become: yesを付けた時点で「~/」は「/root」を指し示した。
become、become_method、become_userの組み合わせで「~/」の指定ユーザに変更することは可能。
playbookのコメントでファイルが作成された位置を追記しています。

実験のplaybookの内容

ansible-playbook -i hosts_vagrant playbook_test20160811.yml --tags debug数字で実験した

- hosts: targets

  tasks:
    # /home/vagrant/20160811
    - name: "debug1"
      file:
        path: "~/20160811"
        state: touch
      tags:
        - debug1

    # /root/20160811
    - name: "debug2"
      become: yes
      file:
        path: "~/20160811"
        state: touch
      tags:
        - debug2

    # /home/vagrant/20160811
    - name: "debug3"
      shell: /bin/bash -lc "touch ~/20160811"
      tags:
        - debug3

    # /root/20160811
    - name: "debug4"
      become: yes
      shell: /bin/bash -lc "touch ~/20160811"
      tags:
        - debug4

    # /home/vagrant/20160811
    - name: "debug5"
      shell: /bin/bash -lc "touch 20160811"
      args:
        chdir: "~"
      tags:
        - debug5

    # /root/20160811
    - name: "debug6"
      become: yes
      shell: /bin/bash -lc "touch 20160811"
      args:
        chdir: "~"
      tags:
        - debug6

    # /home/vagrant/20160811
    - name: "debug7"
      become: yes
      become_user: "vagrant"
      become_method: su
      shell: /bin/bash -lc "touch ~/20160811"
      tags:
        - debug7

    # /home/vagrant/20160811
    - name: "debug8"
      become: yes
      become_user: "vagrant"
      become_method: su
      shell: /bin/bash -lc "touch 20160811"
      args:
        chdir: "~"
      tags:
        - debug8