Re: Test failures with GNU grep 2.23

On Fri, Feb 19, 2016 at 6:59 AM, Jeff King [off-list ref] wrote:

On Sun, Feb 07, 2016 at 04:25:40PM +0000, John Keeping wrote:

quoted

The following patch fixes the tests for me, but I wonder if "-a" is
supported on all target platforms (it's not in POSIX, which specifies
that the "input files shall be text files") or whether we should do
something more comprehensive to provide sane_{e,f,}grep which guarantee
to treat input as text.

I also tried setting POSIXLY_CORRECT but that doesn't affect the
text/binary decision.

Yeah, I'd worry that "-a" is not portable. OTOH, BSD grep seems to have
it, so between that and GNU, I think most systems are covered.

Mac OS X grep seems to support -a and tests in t8005 still pass with
-a added to the egrep invocations.

We could
do:

  test_lazy_prereq GREP_A '
        echo foo | grep -a foo
  '

and mark these tests with it. I'd also be happy to skip that step and
just do it if and when somebody actually complains about a system
without it (I wouldn't be surprised if most people on antique systems
end up installing GNU grep anyway).

Another option might be using "sed -ne '/^author/p'" or similar. But
that may very well just be trading one portability problem for another.

I also wondered whether we could get away without grepping at all here.
But the blame output has a bunch of cruft we don't care about; I think
the readability of the tests would suffer if we tried to match the whole
thing in a test_cmp.

-Peff