graft: test coverage of grafts and how merges can break duplicate detection
This demonstrates unfortunate behaviour: extending the graft range cause the
graft to behave differently. When the graft range includes a merge, we fail to
detect duplicates that are ancestors of the merge.
bdiff: proxy through mdiff module
See the previous commit for why.
mdiff seems a good place to host bdiff functions. bdiff.bdiff was already
aliased as textdiff, so we use it.
base85: proxy through util module
I'm going to replace hgimporter with a simpler import function, so we can
access to pure/cext modules by name:
# util.py
base85 = policy.importmod('base85') # select pure.base85 or cext.base85
# cffi/base85.py
from ..pure.base85 import * # may re-export pure.base85 functions
This means we'll have to use policy.importmod() function in place of the
standard import statement, but we wouldn't want to write it every place where
C extension modules are used. So this patch makes util host base85 functions.
strip: make tree stripping O(changes) instead of O(repo)
The old tree stripping logic iterated over every tree revlog in the repo looking
for commits that had revs to be stripped. That's very inefficient in large
repos. Instead, let's look at what files are touched by the strip and only
inspect those revlogs.
I don't have actual perf numbers, since internally we don't use a true
treemanifest, but simply iterating over hundreds of thousands of revlogs takes
many, many seconds, so this should help tremendously when stripping only a few
commits.
strip: move tree strip logic to it's own function
This will allow external extensions to modify tree strip behavior more
precisely.
manifest: remove unused property _oldmanifest
The last use seems to have gone away in
7c7d845f8b64 (manifest: make
manifestlog use it's own cache, 2016-11-10).