Re: [PATCH] test-lib: try harder to ensure a working jgit

[Todd Zullinger <tmz@pobox.com>]

Hi,

Ævar Arnfjörð Bjarmason wrote:
> 
> On Tue, May 14 2019, Jonathan Nieder wrote:
> 
>> Todd Zullinger wrote:
>>
>>> The JGIT prereq uses 'type jgit' to determine whether jgit is present.
>>> While this should be sufficient, if the jgit found is broken we'll waste
>>> time running tests which fail due to no fault of our own.
>>>
>>> Use 'jgit --version' instead, to catch some badly broken jgit
>>> installations.
>>>
>>> Signed-off-by: Todd Zullinger <tmz@pobox.com>
>>> ---
>>> I ran into such a broken jgit on Fedora >= 30¹.  This is clearly a
>>> problem in the Fedora jgit package which will hopefully be resolved
>>> soon.  But it may be good to avoid wasting time debugging tests which
>>> fail due to a broken tool outside of our control.
>>>
>>> ¹ https://bugzilla.redhat.com/1709624
>>
>> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
>>
>> It would be nice to describe that bug in the commit message, to save
>> readers some head scratching.
> 
> FWIW the jgit in Debian testing/unstable is similarly broken right now:
[...]

Hah, small world. :)

> So rather than describe specific bugs on RedHat/Debian maybe just say:
> 
>     This guards against cases where jgit is present on the system, but
>     will fail to run, e.g. because of some JRE issue, or missing Java
>     dependencies. Seeing if it gets far enough to process the
>     "--version" argument isn't perfect, but seems to be good enough in
>     practice. It's also consistent with how we detect some other
>     dependencies, see e.g. the CURL and UNZIP prerequisites.

Well said.  I indeed avoided putting the detail into the
commit message because it was such a Fedora-specific bug.
I'll update the commit message to add more details though,
borrowing liberally from^W^W^Wperhaps stealing your
suggested wording.

Thanks!

-- 
Todd