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`.
$ NO_FALLBACK="env RHG_ON_UNSUPPORTED=abort"
$ cat << EOF >> $HGRCPATH
> [format]
> sparse-revlog = no
> EOF
$ hg init repo --config format.generaldelta=no --config format.usegeneraldelta=no
$ cd repo
$ (echo header; seq.py 20) > f
$ hg commit -q -Am initial
$ (echo header; seq.py 20; echo footer) > f
$ hg commit -q -Am x
$ hg update ".^"
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ (seq.py 20; echo footer) > f
$ hg commit -q -Am y
$ hg debugdeltachain f --template '{rev} {prevrev} {deltatype}\n'
0 -1 base
1 0 prev
2 1 prev
rhg works on non-generaldelta revlogs:
$ $NO_FALLBACK hg cat f -r .
1
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footer