Requisites 'onlyif'/'unless' ignored in some cases

[cr1st1p]

Description of Issue

I have some states with 'unless' that are running regardless of the unless condition exit code.

Setup

After lot of lost time, I deduced that the problem is that in some conditions, when a salt python exception is thrown, the onlyif/unless conditions are not evaluated anymore in next state entries.

I succeeded in reproducing with a smaller state:

zsh_fail_1:
  cmd.run:
    - name: echo hey
    - runas: cristi
    - unless: test -d ~/.zinit/bin    

zsh_test_1:
  cmd.run:
    - name: echo "t1"
    - onlyif: /bin/false

When I used some 'test.fail_without_changes' state for 'zsh_fail_1', 'zsh_test_1' is working ok.
But if you try using it as above, the zsh_test_1 command is executed!

The important part here is that user 'cristi' does not exist, so code gets some python exception like below:

----------
          ID: zsh_fail_1
    Function: cmd.run
        Name: echo hey
      Result: False
     Comment: An exception occurred in this state: Traceback (most recent call last):
                File "/usr/lib/python3/dist-packages/salt/modules/cmdmod.py", line 442, in _run
                  pwd.getpwnam(runas)
              KeyError: "getpwnam(): name not found: 'cristi'"
              
              During handling of the above exception, another exception occurred:
              
              Traceback (most recent call last):
                File "/usr/lib/python3/dist-packages/salt/state.py", line 1981, in call
                  **cdata['kwargs'])
                File "/usr/lib/python3/dist-packages/salt/loader.py", line 1977, in wrapper
                  return f(*args, **kwargs)
                File "/usr/lib/python3/dist-packages/salt/states/cmd.py", line 892, in run
                  cret = mod_run_check(cmd_kwargs, onlyif, unless, creates)
                File "/usr/lib/python3/dist-packages/salt/states/cmd.py", line 366, in mod_run_check
                  cmd = __salt__['cmd.retcode'](unless, ignore_retcode=True, python_shell=True, **cmd_kwargs)
                File "/usr/lib/python3/dist-packages/salt/modules/cmdmod.py", line 2277, in retcode
                  **kwargs)
                File "/usr/lib/python3/dist-packages/salt/modules/cmdmod.py", line 445, in _run
                  'User \'{0}\' is not available'.format(runas)
              salt.exceptions.CommandExecutionError: User 'cristi' is not available
     Started: 11:52:32.097022
    Duration: 9.035 ms
     Changes:   
----------
          ID: zsh_test_1
    Function: cmd.run
        Name: echo "t1"
      Result: True
     Comment: Command "echo "t1"" run
     Started: 11:52:32.106490
    Duration: 37.838 ms
     Changes:   
              ----------
              pid:
                  30057
              retcode:
                  0
              stderr:
              stdout:
                  t1

Steps to Reproduce Issue

See above.

Versions Report

Salt Version:
           Salt: 3000
 
Dependency Versions:
           cffi: Not Installed
       cherrypy: Not Installed
       dateutil: 2.6.1
      docker-py: Not Installed
          gitdb: Not Installed
      gitpython: Not Installed
         Jinja2: 2.10
        libgit2: Not Installed
       M2Crypto: Not Installed
           Mako: Not Installed
   msgpack-pure: Not Installed
 msgpack-python: 0.5.6
   mysql-python: Not Installed
      pycparser: Not Installed
       pycrypto: 2.6.1
   pycryptodome: Not Installed
         pygit2: Not Installed
         Python: 3.6.9 (default, Nov  7 2019, 10:44:02)
   python-gnupg: 0.4.1
         PyYAML: 3.12
          PyZMQ: 16.0.2
          smmap: Not Installed
        timelib: Not Installed
        Tornado: 4.5.3
            ZMQ: 4.2.5
 
System Versions:
           dist: Ubuntu 18.04 bionic
         locale: UTF-8
        machine: x86_64
        release: 5.4.18-1-MANJARO
         system: Linux
        version: Ubuntu 18.04 bionic

Strange value for the 'System Versions' 'release' field. Looks more like the kernel's name - I'm running salt inside an ubuntu LXD container on a Manjaro distro.

[Ch3LL]

i was able to replciate this on 2019.2.2, 3000 and the head of master. this will need to be fixed up thanks

[mchugh19]

@Ch3LL as of the current master branch, some modules have their own handling for requisites such as unless/onlif. cmd is one of them, so this error is currently raised from that module.

As of neon, the unless/onlyif requisites were enhanced to allow not just shell commands for their logic, but to also support using salt execution module results. As the main requisites have been getting enhanced, this has left the local requisite handling of the few modules working that way to languish. This was discussed briefly in #55938.

To correct the mixed behavior where some modules use the global requisite system and have the full documented functionality, while others like cmd have more limited functionality, I've evaluated and unified on the global requisites in #55974. Seeing this issue, I just corrected this error there as well.

So rather than fix this in the modules/cmdmod.py, I suggest waiting for #55974 which fixes it in state.py.