match: strengthen visit_children_set invariant, Recursive means "all files"
My previous interpretation of "Recursive" was too relaxed: I thought it
instructed the caller to do something like this:
> you can stop calling `visit_children_set` because you'll need to descend into
> every directory recursively, but you should still check every file if it
> matches or not
Whereas the real instruction seems to be:
> I guarantee that everything in this subtree matches, you can stop
> querying the matcher for all files and dirs altogether.
The evidence to support this:
- the test actually passes with the stronger invariant, revealing no
exceptions from this rule
- the implementation of `visit_children_set` for `DifferenceMatcher`
clearly relies on this requirement, so it must hold for that not to
lead to bugs.
Define helpers.
$ hg_log () { hg log -G -T "{rev}:{node|short}"; }
$ commit () { echo "foo - ${2:-$1}" > $1; hg commit -Aqm "Edited $1"; }
$ strip() { hg --config extensions.strip= strip -q -r "$1" ; }
Setup hg repo.
$ hg init repo
$ cd repo
$ touch x; hg add x; hg commit -m "initial"
$ hg clone -q . ../clone
$ commit a
$ cd ../clone
$ commit b
$ hg pull -q ../repo
$ cat .hg/cache/branch2-visible
222ae9789a75703f9836e44de7db179cbfd420ee 2
a3498d6e39376d2456425dd8c692367bdbf00fa2 o default
222ae9789a75703f9836e44de7db179cbfd420ee o default
$ hg_log
o 2:222ae9789a75
|
| @ 1:a3498d6e3937
|/
o 0:7ab0a3bd758a
$ strip '1:'
The branchmap cache is not adjusted on strip.
Now mentions a changelog entry that has been stripped.
$ cat .hg/cache/branch2-visible
222ae9789a75703f9836e44de7db179cbfd420ee 2
a3498d6e39376d2456425dd8c692367bdbf00fa2 o default
222ae9789a75703f9836e44de7db179cbfd420ee o default
$ commit c
Not adjusted on commit, either.
$ cat .hg/cache/branch2-visible
222ae9789a75703f9836e44de7db179cbfd420ee 2
a3498d6e39376d2456425dd8c692367bdbf00fa2 o default
222ae9789a75703f9836e44de7db179cbfd420ee o default
On pull we end up with the same tip, and so wrongly reuse the invalid cache and crash.
$ hg pull ../repo 2>&1 | grep 'ValueError:'
ValueError: node a3498d6e39376d2456425dd8c692367bdbf00fa2 does not exist (known-bad-output !)