AT_TESTED and (non)fatal errors

[Ralf Wildenhues]

Sorry for the crosspost.

I would like to run the Autotest testsuite of Libtool HEAD on systems
which do not have all AT_TESTED() programs available, or possibly under
a different name.

Right now, the testsuite fails when it there is at least one program
missing which is necessary for one test, even if all I want is to run
some other test which does not need the program.  Ideally, I would like
something like SKIP if the program is not available, and AT_TESTED to
allow to work more test-local.

Furthermore, I would like the names to be overridable, as in
  AUTORECONF=autoreconf259

What is the best way around this, short of creating stub commands in
$PATH somewhere (which I don't think I can force users to do)?
Or should we just ditch AT_TESTED and write our own little macro?

Thanks,
Ralf