Bug#930487: lintian: use GitLab caching of test packages to speed up test suite CI

[Felix Lechner <felix.lechner@lease-up.com>]

Hi,

On Sun, Jul 21, 2019 at 6:28 AM Chris Lamb <lamby@debian.org> wrote:
>
> Felix Lechner wrote:
>
>  $ find t/ debian/ -type f | sort | xargs sha1sum | sha1sum | cut -d' ' -f1

That's the same approach I suggested, except I would save the result of

   find t/ debian/ -type f | sort | xargs sha1sum

and do so on a per-test basis. Then t/bin/runtest can rebuild the test
packages adaptively.

Please remember, contributors currently cannot run tests with
'--onlyrun=check:XXX' when they add or change a tag, except after the
time-consuming 'rm -rf debian/test-out; t/bin/build-test-packages'.
(It was much faster until I separated the building of test packages.)
The adaptive rebuilding would be super helpful even without caching on
Salsa.

> .. throwing the entire set of build packages away in the case of cache
> miss.

I did not suggest by-package caching on Salsa. I would write the test
packages in to a different directory tree in d/test-out and only cache
that.

For example, I would write the filled templates to d/test-out/src.
Only this tree needs to be hashed. During building, I would then write
the test packages to d/test-out/built. Only that tree needs to be
cached.

> Anyway, without the Salsa caching working, all of this is moot.
>

One small step for a man; one big step for mankind. :)