subrepo: implement "storeclean" method for mercurial subrepos
The mercurial subrepo "storeclean" method works by calculating a "store hash" of
the repository state and comparing it to a cached store hash. The store hash is
always cached when the repository is cloned from or pushed to a remote
repository, but also on pull as long as the repository already had a clean
store. If the hashes match the store is "clean" versus the selected repository.
Note that this method is currenty unused, but it will be used by a later patch.
The store hash is calculated by hashing several key repository files, such as
the bookmarks file the phaseroots file and the changelog. Note that the hash
comparison is done file by file so that we can exit early if a pair of hashes
do not match. Also the hashes are calculated starting with the file that is
most likely to be smaller upto the file that is more likely to be larger.
Source bundle was generated with the following script:
# hg init
# echo a > a
# ln -s a l
# hg ci -Ama -d'0 0'
# mkdir b
# echo a > b/a
# chmod +x b/a
# hg ci -Amb -d'1 0'
$ hg init
$ hg -q pull "$TESTDIR/bundles/test-manifest.hg"
The next call is expected to return nothing:
$ hg manifest
$ hg co
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg manifest
a
b/a
l
$ hg manifest -v
644 a
755 * b/a
644 @ l
$ hg manifest --debug
b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644 a
b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 755 * b/a
047b75c6d7a3ef6a2243bd0e99f94f6ea6683597 644 @ l
$ hg manifest -r 0
a
l
$ hg manifest -r 1
a
b/a
l
$ hg manifest -r tip
a
b/a
l
$ hg manifest tip
a
b/a
l
$ hg manifest --all
a
b/a
l
The next two calls are expected to abort:
$ hg manifest -r 2
abort: unknown revision '2'!
[255]
$ hg manifest -r tip tip
abort: please specify just one revision
[255]