Deprecate --interpreter-constraints option where it no-ops

[Eric-Arellano]

There are several places now where --interpreter-constraints is never used, or it's exceedingly rare to be used so it's misleading to have as an option.

This also fixes Pylint to ensure that no matter what, the tool Pex uses the same constraints as the requirements Pex. It looks like this was happening in practice, but it's important to enforce to avoid a Pex runtime error about "Missing Wheels".

Finally, this fixes setuptools to have default constraints, which it needs.

[ci skip-build-wheels]
[ci skip-rust]

[Eric-Arellano]

Broken out of #10820, as that implementation is going to change a lot. This should have been a dedicated PR either way.

[Eric-Arellano]

This seems to have broken the Build Wheels shards.

[Eric-Arellano]

This seems to have broken the Build Wheels shards.

It's for some reason fixed by this change:

diff --git a/src/python/pants/backend/python/subsystems/setuptools.py b/src/python/pants/backend/python/subsystems/setuptools.py
index 6f08409af..8c12a8b51 100644
--- a/src/python/pants/backend/python/subsystems/setuptools.py
+++ b/src/python/pants/backend/python/subsystems/setuptools.py
@@ -12,5 +12,5 @@ class Setuptools(PythonToolBase):
     options_scope = "setuptools"
     default_version = "setuptools>=50.3.0,<50.4"
     default_extra_requirements = ["wheel==0.35.1"]
-    register_interpreter_constraints = True
-    default_interpreter_constraints = ["CPython>=3.5"]
+    # register_interpreter_constraints = True
+    # default_interpreter_constraints = ["CPython>=3.5"]

I have no idea why that would be. Why does the interpreter we run setuptools.pex with have an impact on whether the built wheel is compatible with Python 3.7? cc @benjyw if you have ideas

Note that the failure is only when using PY=python3.7 and PY=python3.8. The default, which uses python3.6, passes.

[Eric-Arellano]

Okay, I think I see the issue. We only run setup-py with bdist_wheel for pantsbuild.pants. No --python-tag. This means that setuptools uses the interpreter it's running with to determine the ABI, afaict, e.g. cp36-cp36m-macosx_10_15_x86_64.

Now that we've set the interpreter constraints for setuptools, it's always using the minimum version of 3.6 no matter what. I'm still unclear on why it was working previously; I don't see why us setting PY=python3.7 and --python-setup-interpreter-constraints=['==3.7.*'] would influence what setuptools is run with. It seems finicky that this was working in the first place.

The solution is for our release script to set --setuptools-interpreter-constraints to the interpreter we want. That's fine for us. But this doesn't seem ideal for end users. I think we need to make some improvements to setup-py, including:

1. Start embedding more information like bdist_wheel args in the BUILD file.
2. Figure out this story on interpreter constraints.