Stu Hood

Thanks a lot @jyggen!

I think that regardless of whether `PEX_EXTRA_SYS_PATH` works in this version (it sounds like it probably moved from not-working to working?), it seems like it should be stripped during the...

Frustratingly, this doesn't repro when Pants is run from sources. So will need a repro in an integration test.

The comment from https://github.com/pantsbuild/pants/blob/aaaedbb01c3f8b4c5a26bc6fee601418e4cd551c/src/python/pants/backend/python/goals/run_helper.py#L76-L79 was added in #12060. Things are tricky, but: on `main`, there is a deprecation in place that will remove executing `pex_binary`s via "cobbling". So: 1. (**deprecated**)...

(sorry: made a bunch of edits to the previous item: best to view in github's UI to see the latest)

> `PEX_EXTRA_SYS_PATH` lives on as a way to modify the --venv pex `sys.path` at runtime: > https://github.com/pantsbuild/pex/blob/54fb072e5258215c3a0d5ec4e2fb406c17093644/pex/venv/pex.py#L466-L476 Hm. I think that that means that regardless of whether `--no-strip-pex-env` is set,...

> BUT. I just noticed that item 2 and item 3 from the description don't quite make sense, because the `pants` script does this: https://github.com/pantsbuild/setup/blob/eb887ad5fd80766214e8c38102a5bc92d1342beb/pants#L282-L295 ... so I should be...

Given that the deprecation of: ``` use_deprecated_pex_binary_run_semantics = true ``` ...will resolve this for existing users, I'm going to attempt to punt on fixing this for case `#3` from https://github.com/pantsbuild/pants/issues/16325#issuecomment-1218386421...

> I'd love to get a handle on how we're so often wrong on these things. The longer more awkward name was intentional while the feature was experimental: we had...

Reusing the "shape" of the `set_defaults` API, but within an options scope could make sense. ```toml [target.defaults] python_tests = { platforms = [] } ```