[stdlib-sig] bootstrapping test suite

[Allison Randal]

For Pynie we're developing a bootstrapping test suite, which may be 
useful to other implementations as they migrate to 3.x. It uses Robert 
Collins' SubUnit, which decouples the testing framework from the tests. 
So the testing framework runs in CPython (or any reasonably complete 
Python 2.x implementation), while the tests run in Pynie. All that's 
required to pass the first test is an implementation of 'print' and 
string constants. The tests gradually build up in complexity through 
numeric constants, operators, control structures, functions, etc, and 
when we're done with them will walk all the way through to supporting 
the full Python 3.x syntax. When the bootstrap is complete, the test 
framework moves to Pynie too, integrated with the core CPython test suite.

It might eventually be useful to add to the py3k branch, though I 
wouldn't include it in release tarballs. Or, if another repo is started 
for the benchmark tests, the bootstrapping tests might be added there. 
We'll contribute it to the PSF, anyway, so it's available. It does 
depend on SubUnit, which isn't part of the standard library. I can strip 
it down to a minimal subset of SubUnit's features and include them in 
the test running script if that makes it more generally useful.

Right now the tests live in Lib/test/parrot in the Pynie repository, but 
will likely move to Lib/test/bootstrap (suggestions on Python-friendly 
naming welcome).

Allison