t/aclocal-print-acdir.sh at installcheck and AUTOMAKE_UNINSTALLED

[Karl Berry]

The aclocal-print-acdir.sh test fails at the make installcheck step of
make distcheck (it succeeds in the normal make check, and it succeeds at
the make check of make distcheck; only fails in the make installcheck).

This is because AUTOMAKE_UNINSTALLED is (correctly) set in the
environment at that point, which causes aclocal-1.16 --print-ac-dir
to forcibly return the empty string, which does not match the expected
acdir string:

  + aclocal-1.16 -Werror --print-ac-dir

  test "$($ACLOCAL --print-ac-dir)" = "$am_system_acdir"
  ++ aclocal-1.16 -Werror --print-ac-dir
  + test '' = /u/karl/gnu/src/akarl/automake-1.16a/_inst/share/aclocal
  am_exit_trap $?
  + am_exit_trap 1

Per this bit in the aclocal-1.16 Perl script:

  if (exists $ENV{"AUTOMAKE_UNINSTALLED"})
    {
      @automake_includes = ();
      @system_includes = ();
    }

(The --print-ac-dir option simply prints the value of @system_includes.)

So, if I unset AUTOMAKE_UNINSTALLED in the test, it works:
test "$am_running_installcheck" = yes && unset AUTOMAKE_UNINSTALLED || :

Since this test is intended to check exactly a value that only is set
normally in an installation, that seems like a reasonable thing to do.

But I am not sure. Jim, anyone with more experience, can you confirm/deny?

Thanks,
Karl

P.S. This also fails for me if I run make installcheck after
building the released automake-1.16.

P.P.S. There are two other tests, print-libdir and aclocal-print-acdir,
which also fail at the make installcheck step of make distcheck, and not
sooner. Unfortunately they are not solved by unsetting
AUTOMAKE_UNINSTALLED, though I think the problem is generally similar.