Re: [PATCH 00/11] t: reduce direct disk access to data structures

Han-Wen Nienhuys [off-list ref] writes:

I think it would be really great if there were separate unittests for
the ref backend API. Some of the reftable work was needlessly
difficult because the contract of the API was underspecified. The API
is well compartmentalized in refs-internal.h, and a lot of the API
behavior can be tested as a black box, eg.

* setup symref HEAD pointing to R1
* setup transaction updating ref R1 from C1 to C2
* commit transaction, check that it succeeds
* read ref R1, check if it is C2
* read reflog for R1, see that it has a C1 => C2 update
* read reflog for HEAD, see that it has a C1 => C2 update

Tests for the loose/packed backend could directly mess with the
on-disk files to test failure scenarios.

With unittests like that, the tests can zoom in on the functionality
of the ref backend, and provide more convenient coverage for
dynamic/static analysis.

Yeah, I agree that something like that would really be great.