tests: add tests and document expectations from visit_children_set in rust
The tests this patch are adding have the form of formal spec in
invariants::visit_children_set::holds,
and then a series of checks that all examples must satisfy this
formal spec.
I tried to make the spec consistent with how this function is used
and how it was originally conceived. This is in conflict with how it's
documented in Rust. Some of the implementations also fail to implement
this spec, which leads to bugs, in particular when complicated patterns
are used with `hg status`.
# stack.py - Mercurial functions for stack definition
#
# Copyright Olivia Mackall <olivia@selenic.com> and other
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
def getstack(repo, rev=None):
"""return a sorted smartrev of the stack containing either rev if it is
not None or the current working directory parent.
The stack will always contain all drafts changesets which are ancestors to
the revision and are not merges.
"""
if rev is None:
rev = b'.'
revspec = b'only(%s) and not public() and not ::merge()'
revisions = repo.revs(revspec, rev)
revisions.sort()
return revisions