issue-6028: resolves 6028 - return (False, ".") instead of (False, '') Since 4.8, repo[] no longer takes an empty string, so we update to a valid with similar semantic. This value is strange and we should probably use an actual node ID here, however, this is an independent issue.

branching: merge with stable

tests: add sparserevlog cap since hg now has sparse revlogs by default CORE-TEST-OUTPUT-UPDATE: 3764330f76a6

split: rework the prompt to be more standard We dropped the initial capital and moved to a positive question.

split: add a option to discard remaining change during split This is useful to drop unwanted remaining change spotted during the split.

split: add a way to abort a split from the prompt This prompt is asking the user about the next step. Offering to abort there make sense.

split: add a help entry to the final prompt We are about to add more option in this prompt. Adding a way to document then seems like a good first step.

topic: make revset argument messages be similar to such messages in core

tests: don't forget to add hg serve pid to DAEMON_PIDS in test-wireproto.t Otherwise it leaves a process running after each run-tests.py launch.

test: adapt to change output change on default We now have a `wcache` directory in `.hg`.