treemanifest: add walksubtrees api
Adds a new function to treemanifest that allows walking over the directories in
the tree. Currently it only accepts a matcher to prune the walk, but in the
future it will also accept a list of trees and will only walk over subtrees that
differ from the versions in the list. This will be useful for identifying what
parts of the tree are new to this revision, which is useful when deciding the
minimal set of trees to send to a client given that they have a certain tree
already.
Since this is intended for an extension to use, the only current consumer is a
test. In the future this function may be useful for implementing other
algorithms like diff and changegroup generation.
Just exercise debugindexdot
Create a short file history including a merge.
$ hg init t
$ cd t
$ echo a > a
$ hg ci -qAm t1 -d '0 0'
$ echo a >> a
$ hg ci -m t2 -d '1 0'
$ hg up -qC 0
$ echo b >> a
$ hg ci -m t3 -d '2 0'
created new head
$ HGMERGE=true hg merge -q
$ hg ci -m merge -d '3 0'
$ hg debugindexdot .hg/store/data/a.i
digraph G {
-1 -> 0
0 -> 1
0 -> 2
2 -> 3
1 -> 3
}
$ cd ..