Message8827

I'm taking my usual approach of inspecting and commenting what we've got, ahead of any change. I notice we are also divergent in our handling of field numbering. CPython:
>>> list("hello {!r:#12x} and {!s:8.3f} world!"._formatter_parser())
[('hello ', '', '#12x', 'r'), (' and ', '', '8.3f', 's'), (' world!', None, None, None)]
>>>

Jython:
>>> list("hello {!r:#12x} and {!s:8.3f} world!"._formatter_parser())
[('hello ', '0', '#12x', 'r'), (' and ', '1', '8.3f', 's'), (' world!', None, None, None)]
>>>

Not the cause of this bug, I know.