Re: [PATCH v2 1/5] cmake: make it easier to diagnose regressions in CTest runs

[Eric Sunshine <ericsunshine@gmail.com>]

On Thu, Sep 8, 2022 at 3:28 AM Ævar Arnfjörð Bjarmason <avarab@gmail.com> wrote:
> On Tue, Aug 23 2022, Johannes Schindelin via GitGitGadget wrote:
> > When a test script fails in Git's test suite, the usual course of action
> > is to re-run it using options to increase the verbosity of the output,
> > e.g. `-v` and `-x`.
> > [...]
> > Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> > ---
> > diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
> > +             COMMAND ${SH_EXE} ${tsh} --no-bin-wrappers --no-chain-lint -vx
>
> I think the "--no-bin-wrappers --no-chain-lint" and the "while at it"
> here should be stripped out, and put into its own commit.
>
> So, perhaps we should have a performance hack due to Windows's slowness,
> but:
>
>  C. Since I sent [1] we've had submitted chainlint.pl in-flight
>     series. It's partly trying to take special considerations to be fast
>     on Windows. I don't think it's the case with that series that this
>     needs to be skipped on Windows anymore (and if it is, Eric would
>     like to know).

I had the opportunity to test chainlint.pl on an 8-core machine using
both Linux and Windows 10. The machine is more than a few years old,
though not nearly as old as my own development machine. Although
chainlint.pl checked all test definitions in the entire project in
less than one _second_ on Linux, it took two _minutes_ on Windows 10
on the same machine (using all 8 cores). Despite the fact that Perl is
run just once to check all test definitions -- unlike chainlint.sed
running 'sed' tens of thousands of times, chainlint.pl is still
painfully slow on Windows, so I certainly understand the desire to use
--no-chain-lint, at least on Windows.