As of version 0.16.0, vdirsyncer now uses SQLite for some of its internal metadata. Therefore it needs to depend on dev-lang/python[sqlite], not just dev-lang/python.
Thank you for your report, do you have a link for the maintainer where this information is from, or did you assume it from the code?
<https://github.com/pimutils/vdirsyncer/blob/master/CHANGELOG.rst>, version 0.16.0, sixth bullet point.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=7448437313040b4f25c06a86725932483d7081e8 commit 7448437313040b4f25c06a86725932483d7081e8 Author: Amy Liffey <amynka@gentoo.org> AuthorDate: 2017-10-09 19:22:09 +0000 Commit: Amy Liffey <amynka@gentoo.org> CommitDate: 2017-10-09 19:23:13 +0000 dev-python/vdirsyncer: add req python use sqlite Suggested-by: Christopher Head <chead@chead.ca> Closes: https://bugs.gentoo.org/630060 Package-Manager: Portage-2.3.6, Repoman-2.3.1 .../vdirsyncer/{vdirsyncer-0.16.0.ebuild => vdirsyncer-0.16.0-r1.ebuild} | 1 + 1 file changed, 1 insertion(+)