BackendUnavailable when specifying backend-path (original) (raw)

Environment

• pip version: 19.1.1
• Python version: 3.7.3
• OS: Linux

After extensive discussion, PEP 517 was amended to add a backend-path key to allow bootstrapped backends. I modified the build-system section of pyproject.toml in setuptools to be:

[build-system] requires = ["wheel"] build-backend = "setuptools.build_meta" backend-path = ["."]

But installing setuptools with pip install -t tmp/ . is still failing with BackendUnavailable. Did anyone get around to implementing this functionality after the discussion? I don't see any PR or issue tracking it, so I figured I'd start one.