Re: pgsql: Add basic TAP tests for psql's tab-completion logic.

I wrote:
> Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com> writes:
>> I think he means something like
>> make check with_readline=no
>> not for the actual build.

> Oh, I see. I'd rather not codify that though, because it risks
> problems if that symbol ever gets used any other way. I was
> thinking of making the test script check for some independent
> environment variable, say SKIP_READLINE_TESTS.

I thought of another problem with the with_readline=no method,
which is that it requires the user to be issuing "make check"
directly; it wouldn't be convenient for a buildfarm owner, say.
(*Perhaps* it'd work to set with_readline=no throughout a
buildfarm run, but I think that's asking for trouble with the
build part.) I pushed a patch using SKIP_READLINE_TESTS.
Christoph should be able to set that for the Ubuntu branches
where the test is failing.

regards, tom lane