Re: Do test-path_is_{file,dir,exists} make sense anymore with -x?

From: Junio C Hamano <gitster@pobox.com>
Date: Mar 1, 2019, 02:52 UTC
Message-ID: <xmqqzhqf8fw5.fsf@gitster-ct.c.googlers.com>
In-Reply-To: <87sgwav8cp.fsf@evledraar.gmail.com>

Ævar Arnfjörð Bjarmason <avarab@gmail.com> writes:

Show 12 quoted lines

> I swear I'm not just on a mission to ruin everyone's GSOC projects. This
> patch definitely looks good, and given that we have this / document it
> makes sense.
>
> However. I wonder in general if we've re-visited the utility of these
> wrappers and maybe other similar wrappers after -x was added.
>
> Back when this was added in 2caf20c52b ("test-lib: user-friendly
> alternatives to test [-d|-f|-e]", 2010-08-10) we didn't have -x.
> ...
> But 4 years after this was added in a136f6d8ff ("test-lib.sh: support -x
> option for shell-tracing", 2014-10-10) we got -x, and then with "-i -v -x":

I think two things need to be considered separately.

 - Do the path-is-file and friends make the test source easier to
   read and undrstand?  Special bonus if it helps us by making it
   harder to write a wrong test.

 - Do these helpers make the output from the test execution easier
   to diagnose or harder?

If your primary compalint is the latter (which I think it is, and I share the same feeling to a certain degree), I think it is to throw the baby with bathwater to get rid of path-is-* family.

And as to the former question, I think we even are getting special bonus. Often when people write tests to ensure a fix that left an unwanted file behind would say "! test -f unwanted", but if we say "path-is-missing unwanted" that would catch not just a regular file but also catch other kinds of filesystem entities.

As to readablity, I do not think "test -f/-d" etc are unnecessary hard to read, but using path-is-* does not make it harder to read, so I'd say it would not give us much to revert to the bare "test -f" and friends.

Unless you are after squeezing the last cycle spent executing a shell builtin in the test scripts by using bare-bones "test -f", that is. But that is not among the two I said we need to consider separately, so I won't go there.

Thanks.

[jch: I am still mostly offline til the next week, but I had a chance to sit in front of my mailbox long enough, so...]