[BUG] Parallel states on spawning platforms are missing some global dunders

[lkubb]

Description
On a spawning platform, running a state module relying on dunders like __env__ via parallel: true fails with a NameError (this is probably an issue for __low__, __running__, __instance_id__, __lowstate__ and __user__ as well).

Setup
(Please provide relevant configs and/or SLS files (be sure to remove sensitive info. There is no general set-up of Salt.)

Please be as specific as possible and give set-up details.

• on-prem machine
• onedir packaging

On bare-metal macOS with official 3007.1 package.

Note that Windows is a spawning platform as well.

Steps to Reproduce the behavior

# /opt/srv/salt/fail.sls

foo:
  git.latest:
    - name: https://github.com/saltstack/salt.git
    - target: /tmp/salt
    - parallel: true

salt-call state.apply fail

Expected behavior
The clone works.

Screenshots

----------
          ID: foo
    Function: git.latest
        Name: https://github.com/saltstack/salt.git
      Result: False
     Comment: An exception occurred in this state: Traceback (most recent call last):
                File "/opt/salt/lib/python3.10/site-packages/salt/state.py", line 2161, in _call_parallel_target
                  ret = instance.states[cdata["full"]](*cdata["args"], **cdata["kwargs"])
                File "/opt/salt/lib/python3.10/site-packages/salt/loader/lazy.py", line 160, in __call__
                  ret = self.loader.run(run_func, *args, **kwargs)
                File "/opt/salt/lib/python3.10/site-packages/salt/loader/lazy.py", line 1269, in run
                  return self._last_context.run(self._run_as, _func_or_method, *args, **kwargs)
                File "/opt/salt/lib/python3.10/site-packages/salt/loader/lazy.py", line 1284, in _run_as
                  return _func_or_method(*args, **kwargs)
                File "/opt/salt/lib/python3.10/site-packages/salt/states/git.py", line 726, in latest
                  saltenv=__env__,
              NameError: name '__env__' is not defined
     Started: 10:46:38.229375
    Duration: 7.989 ms
     Changes:

Versions Report

salt --versions-report

(Provided by running salt --versions-report. Please also mention any differences in master/minion versions.)

Salt Version:
          Salt: 3007.1

Python Version:
        Python: 3.10.14 (main, Apr  3 2024, 21:27:26) [Clang 15.0.0 (clang-1500.0.40.1)]

Dependency Versions:
          cffi: 1.16.0
      cherrypy: unknown
      dateutil: 2.8.2
     docker-py: Not Installed
         gitdb: Not Installed
     gitpython: Not Installed
        Jinja2: 3.1.4
       libgit2: Not Installed
  looseversion: 1.3.0
      M2Crypto: Not Installed
          Mako: Not Installed
       msgpack: 1.0.7
  msgpack-pure: Not Installed
  mysql-python: Not Installed
     packaging: 23.1
     pycparser: 2.21
      pycrypto: Not Installed
  pycryptodome: 3.19.1
        pygit2: Not Installed
  python-gnupg: 0.5.2
        PyYAML: 6.0.1
         PyZMQ: 25.1.2
        relenv: 0.16.0
         smmap: Not Installed
       timelib: 0.3.0
       Tornado: 6.3.3
           ZMQ: 4.3.4

Salt Package Information:
  Package Type: onedir

System Versions:
          dist: darwin 23.6.0
        locale: utf-8
       machine: arm64
       release: 23.6.0
        system: Darwin
       version: 14.7 arm64

Additional context
inject_globals is defined in the parent process:

salt/salt/state.py

Lines 2362 to 2372 in d7b4d10

	inject_globals = {
	# Pass a copy of the running dictionary, the low state chunks and
	# the current state dictionaries.
	# We pass deep copies here because we don't want any misbehaving
	# state module to change these at runtime.
	"__low__": immutabletypes.freeze(low),
	"__running__": immutabletypes.freeze(running) if running else {},
	"__instance_id__": self.instance_id,
	"__lowstate__": immutabletypes.freeze(chunks) if chunks else {},
	"__user__": self.opts.get("user", "UNKNOWN"),
	}

__env__ is ensured to be defined in there as well:

salt/salt/state.py

Lines 2414 to 2416 in d7b4d10

	if "__env__" not in inject_globals:
	# Let's use the default environment
	inject_globals["__env__"] = "base"

The parent process' State instance sets the inject_globals attribute on its state loader:

salt/salt/state.py

Line 2422 in d7b4d10

self.states.inject_globals = inject_globals

When parallel is True, self.call_parallel is called

salt/salt/state.py

Lines 2435 to 2437 in d7b4d10

	elif not low.get("__prereq__") and low.get("parallel"):
	# run the state call in parallel, but only if not in a prereq
	ret = self.call_parallel(cdata, low)

On spawning platforms, a new State instance has to be created, which also resets the inject_globals attribute on the state module loader:

salt/salt/state.py

Lines 2283 to 2291 in d7b4d10

	if salt.utils.platform.spawning_platform():
	instance = None
	else:
	instance = self
	proc = salt.utils.process.Process(
	target=self._call_parallel_target,
	args=(instance, self._init_kwargs, name, cdata, low),
	name=f"ParallelState({name})",

And it's never redefined.