Black does not accept multiple top-level as-expressions on a case

[isidentical]

I've modified my script from the original issue to include the whole Lib/test/test_patma.py. It uncovered one potential bug, but other than the good news is we are fully compatible (even though it takes a ridiculously large amount of time to parse that file, twice (due to the second pass)). I still haven't figured out the best way to optimize, but that is on my bucket list.

The only example we can't parse is the following:

def test_patma_238(self):
    x = ((0, 1), (2, 3))
    match x:
        case ((a as b, c as d) as e) as w, ((f as g, h) as i) as z:
            y = 0

Where we have 2 top-level as-expressions (blabla as bla, blabla2 as bla2) it fails to parse since it doesn't recognize as expressions on the individual unparenthesized case expressions.