Difference between become and become_user in Ansible

Question

become_user defines the user which is being used for privilege escalation.

become simply is a flag to either activate or deactivate the same.

Here are three examples which should make it clear:

This task will be executed as root, because root is the default user for privilege escalation:
```
 - do: something
   become: true
```
This task will be executed as user someone, because the user is explicitly set:
```
 - do: something
   become: true
   become_user: someone
```
This task will not do anything with become_user, because become is not set and defaults to false/no:
```
 - do: something
   become_user: someone
```

…unless become was set to true on a higher level, e.g. a block, the playbook, group or host-vars etc.

Here is an example with a block:

    - become: true
      block:
        - do: something
          become_user: someone
        - do: something

The first 1st is ran as user someone, the 2nd as root.

As I understand it become_user is something similar to su , and become means something like sudo su or “perform all commands as a sudo user”.

The default become_method is sudo, so sudo do something or sudo -u <become_user> do something

_{^{Fineprint: Of course “do: something” is pseudocode. Put your actual Ansible module there.}}