[pip-compile] Upgrading a dependency with -P that has extras fails with backtracking resolver

[nwalsh1995]

Environment Versions

1. Python version: 3.7.5
2. pip version: 23.0
3. pip-tools version: 6.12.2

Steps to replicate

1. Create requirements.in file.

# requirements.in
googleapis-common-protos[grpc]==1.56.4
google-api-core[grpc]==1.32.0

2. Attempt upgrading googleapis-common-protos[grpc] with -P and the backtracking resolver

pip-compile -v --resolver backtracking -P googleapis-common-protos\[grpc\] requirements.in

Expected result

pip-compile upgrades googleapis-common-protos\[grpc\] and extra packages.

Actual result

pip._internal.exceptions.InstallationError: Constraints cannot have extras

Note: without --resolver backtracking the call succeeds after multiple rounds.

pip-compile -v -P googleapis-common-protos\[grpc\] requirements.in

Edit: the command also doesn't work with --strip-extras:

$ pip-compile -v --strip-extras --resolver=backtracking -P googleapis-common-protos\[grpc\] requirements.in

pip._internal.exceptions.InstallationError: Constraints cannot have extras

[pawelad]

You should be able to bypass that problem by passing extra --strip-extras option to pip-tools.

[nwalsh1995]

You should be able to bypass that problem by passing extra --strip-extras option to pip-tools.

Hi @pawelad, it doesn't work with --strip-extras either:

$ pip-compile -v --strip-extras --resolver=backtracking -P googleapis-common-protos\[grpc\] requirements.in

pip._internal.exceptions.InstallationError: Constraints cannot have extras

[nwalsh1995]

FYI the patch from @deivid-rodriguez here fixes this issue. Will see if Deivid wants to make the PR.

[deivid-rodriguez]

Happy to provide a PR but as I said over at the dependabot ticket, I did not manage to write a test for it.

[nwalsh1995]

This issue is fixed in #1808 🎉

[atugushev]

Completed via #1808.