Deprecate rsync support

[nicoddemus]

It's possible that the current tests don't correctly capture the requirements in a way that finds breakage.

If that's the case we should evaluate that and consider dropping rsync over fixing it.

Originally posted by @RonnyPfannschmidt in #823 (comment)

[nicoddemus]

We probably can just deprecate in the same way as we did with --boxed:

pytest-xdist/src/xdist/plugin.py

Lines 198 to 205 in 1471164

	if config.getoption("boxed"):
	warning = DeprecationWarning(
	"The --boxed command line argument is deprecated. "
	"Install pytest-forked and use --forked instead. "
	"pytest-xdist 3.0.0 will remove the --boxed argument and pytest-forked dependency."
	)
	config.issue_config_time_warning(warning, 2)
	config.option.forked = True

Except the removal itself will have to happen in pytest-xdist 4.0.

[nicoddemus]

@RonnyPfannschmidt is this something you want to do before the 3.0.0 release?

[RonnyPfannschmidt]

Ideally yes, but my bandwidth this week is unclear

[nicoddemus]

Want me to tackle it?

I think it is important to release 3.0 before or right after pytest 7.2, that's why I ask (but this deprecation can be done later of course).

[RonnyPfannschmidt]

Then let's defer

[nicoddemus]

While I waited for your response I went ahead and opened #828, let me know if that's sufficient or you would like something more elaborate, in which case we can defer it.

[ssbarnea]

While the rsyncdir(s) were deprecated and I am not them anywhere, now I see my test suited failing because I run them with warnings as errors.

That was with latest versions of pytest and its plugins:

INTERNALERROR> Traceback (most recent call last):
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/_pytest/main.py", line 266, in wrap_session
INTERNALERROR>     config._do_configure()
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/_pytest/config/__init__.py", line 1037, in _do_configure
INTERNALERROR>     self.hook.pytest_configure.call_historic(kwargs=dict(config=self))
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/pluggy/_hooks.py", line 277, in call_historic
INTERNALERROR>     res = self._hookexec(self.name, self.get_hookimpls(), kwargs, False)
INTERNALERROR>           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/pluggy/_manager.py", line 80, in _hookexec
INTERNALERROR>     return self._inner_hookexec(hook_name, methods, kwargs, firstresult)
INTERNALERROR>            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/pluggy/_callers.py", line 60, in _multicall
INTERNALERROR>     return outcome.get_result()
INTERNALERROR>            ^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/pluggy/_result.py", line 60, in get_result
INTERNALERROR>     raise ex[1].with_traceback(ex[2])
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/pluggy/_callers.py", line 39, in _multicall
INTERNALERROR>     res = hook_impl.function(*args)
INTERNALERROR>           ^^^^^^^^^^^^^^^^^^^^^^^^^
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/xdist/plugin.py", line 214, in pytest_configure
INTERNALERROR>     config.issue_config_time_warning(warning, 2)
INTERNALERROR>   File "/Users/ssbarnea/c/a/molecule/.tox/py/lib/python3.11/site-packages/_pytest/config/__init__.py", line 1394, in issue_config_time_warning
INTERNALERROR>     warnings.warn(warning, stacklevel=stacklevel)
INTERNALERROR> DeprecationWarning: The --rsyncdir command line argument and rsyncdirs config variable are deprecated.
INTERNALERROR> The rsync feature will be removed in pytest-xdist 4.0.

Am I the only one running with warnings as errors?