tests/test-config-case.t

dirstate: fix some problems for recursive case normalization (issue3342)

file in nested directory causes unexpected abort.

problems below should be fixed for recursive normalization route in
dirstate._normalize():

    1. rsplit() may cause unpacking into more than 2 elements.
       it should be called with 'maxsplit' argument to unpack
       into 'd, f'

    2. 'd' is replaced by normalized value prefixed with
       'self._root', but this makes 'folded' as absolute path,
       and it is unexpected one for caller of recursive
       normalization

  $ echo '[Section]' >> $HGRCPATH
  $ echo 'KeY = Case Sensitive' >> $HGRCPATH
  $ echo 'key = lower case' >> $HGRCPATH

  $ hg showconfig Section
  Section.KeY=Case Sensitive
  Section.key=lower case