`_shell_executable=None` is ignored in inventory

[vojta001]

Describe the bug

Since #724 we can use --shell-executable None in CLI to make pyinfra not explicitly specify a shell (crucial for non-POSIX targets). I struggle to opt in for the same behavior using the inventory file only.

To Reproduce

inventory.py:

test = [
    ("example.tld", {"_shell_executable": None, "ssh_user": "root"})
]

pyinfra -vvv inventory.py exec date

The output is

--> Loading config...

--> Loading inventory...

--> Connecting to hosts...
    [example.tld] Connected
    [example.tld] Ready: shell

--> Proposed changes:
    Groups: test / inventory
    [example.tld]   Operations: 1   Change: 1   No change: 0

--> Beginning operation run...
--> Starting operation: Server/Shell (date)
[example.tld] >>> sh -c date
[example.tld] Sun Feb  4 11:17:36 CET 2024
    [example.tld] Success

--> Results:
    Groups: test / inventory
    [example.tld]   Changed: 1   No change: 0   Errors: 0

Compare it with

pyinfra --shell-executable None -vvv inventory.py exec date

and its output

--> Loading inventory...

--> Connecting to hosts...
    [example.tld] Connected
    [example.tld] Ready: shell

--> Proposed changes:
    Groups: inventory / test
    [example.tld]   Operations: 1   Change: 1   No change: 0

--> Beginning operation run...
--> Starting operation: Server/Shell (date)
[example.tld] >>> date
[example.tld] Sun Feb  4 11:17:59 CET 2024
    [example.tld] Success

--> Results:
    Groups: inventory / test
    [example.tld]   Changed: 1   No change: 0   Errors: 0

It's the [example.tld] >>> sh -c date vs. [example.tld] >>> date.

Meta

• Include output of pyinfra --support.

  --> Support information:
  System: Linux
    Platform: Linux-6.1.75-x86_64-with-glibc2.38
    Release: 6.1.75
    Machine: x86_64
  pyinfra: v2.8
  Executable: /nix/store/pwk54za44zp4q0x6p9sm0vr78s66gcy3-python3.11-pyinfra-2.8/bin/pyinfra
  Python: 3.11.6 (CPython, GCC 12.3.0)

• How was pyinfra installed (source/pip)? distribution's package manager nix

[Fizzadar]

Hi @vojta001, thank you for reporting this. I've pushed a fix (unfortunately messed up the commit here) in https://github.com/pyinfra-dev/pyinfra/commit/8177f500d60a650313f20f2f4cce8f313d41e70c and just released that in v2.9.1. Would you be able to retry to confirm this is fixed?

[Fizzadar]

Fixed, cherry picked into v3 branch.

[vojta001]

@Fizzadar Thank you for fixing this and sorry for the long delay to test the patch. I can now confirm the issue is gone.

[Fizzadar]

@vojta001 no worries at all appreciate you checking in 🙏