[FFe] Implement support for "buttercup_eval"

[Sergio Durigan Junior]

dh-elpa supports the "ert_eval" directive inside d/elpa-test, which allows the package to provide custom Elisp code to be executed before ERT is invoked. Unfortunately, a similar feature is missing for buttercup tests. This means that, whenever a package uses buttercup to run its tests, the maintainer needs to override dh_elpa_test and invoke buttercup by hand. This, however, only works during build time; dh-elpa is also used to run autopkgtest, and in that specific scenario it's not possible to execute custom Elisp code using buttercup at all.

Why is this important, you might ask. Well, I've been investigating a bug in Emacs 28.2's native compilation mechanism which affects a bunch of packages (see bug #2006963 for more details). One of those affected packages is flycheck, which uses buttercup. I uploaded a fix for a flycheck FTBFS which addresses the problem, but the package still fails its autopkgtest because of the problem mentioned above.

Long story short, I've implemented the support for a new dh-elpa directive called "buttercup_eval" and would like it to Lunar. I also proposed the feature to Debian here: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1032202

[Sergio Durigan Junior (sergiodj)]

debdiff containing the proposed change.

[Steve Langasek (vorlon)]

approved

[Launchpad Janitor (janitor)]

This bug was fixed in the package dh-elpa - 2.0.16ubuntu2

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dh-elpa (2.0.16ubuntu2) lunar; urgency=medium

  * dh_elpa_test: Implement new buttercup_eval directive.
    (LP: #2008919)

 -- Sergio Durigan Junior <email address hidden> Wed, 01 Mar 2023 13:08:44 -0500