merge: start using the per-side copy dicts
The point of this patch is mostly to clarify `manifestmerge()`. I find
it much easier to reason about now.
Differential Revision: https://phab.mercurial-scm.org/D7990
# copies.py - copy detection for Mercurial
#
# Copyright 2008 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from __future__ import absolute_import
import collections
import multiprocessing
import os
from .i18n import _
from .revlogutils.flagutil import REVIDX_SIDEDATA
from . import (
error,
match as matchmod,
node,
pathutil,
pycompat,
util,
)
from .revlogutils import sidedata as sidedatamod
from .utils import stringutil
def _filter(src, dst, t):
"""filters out invalid copies after chaining"""
# When _chain()'ing copies in 'a' (from 'src' via some other commit 'mid')
# with copies in 'b' (from 'mid' to 'dst'), we can get the different cases
# in the following table (not including trivial cases). For example, case 2
# is where a file existed in 'src' and remained under that name in 'mid' and
# then was renamed between 'mid' and 'dst'.
#
# case src mid dst result
# 1 x y - -
# 2 x y y x->y
# 3 x y x -
# 4 x y z x->z
# 5 - x y -
# 6 x x y x->y
#
# _chain() takes care of chaining the copies in 'a' and 'b', but it
# cannot tell the difference between cases 1 and 2, between 3 and 4, or
# between 5 and 6, so it includes all cases in its result.
# Cases 1, 3, and 5 are then removed by _filter().
for k, v in list(t.items()):
# remove copies from files that didn't exist
if v not in src:
del t[k]
# remove criss-crossed copies
elif k in src and v in dst:
del t[k]
# remove copies to files that were then removed
elif k not in dst:
del t[k]
def _chain(prefix, suffix):
"""chain two sets of copies 'prefix' and 'suffix'"""
result = prefix.copy()
for key, value in pycompat.iteritems(suffix):
result[key] = prefix.get(value, value)
return result
def _tracefile(fctx, am, basemf):
"""return file context that is the ancestor of fctx present in ancestor
manifest am
Note: we used to try and stop after a given limit, however checking if that
limit is reached turned out to be very expensive. we are better off
disabling that feature."""
for f in fctx.ancestors():
path = f.path()
if am.get(path, None) == f.filenode():
return path
if basemf and basemf.get(path, None) == f.filenode():
return path
def _dirstatecopies(repo, match=None):
ds = repo.dirstate
c = ds.copies().copy()
for k in list(c):
if ds[k] not in b'anm' or (match and not match(k)):
del c[k]
return c
def _computeforwardmissing(a, b, match=None):
"""Computes which files are in b but not a.
This is its own function so extensions can easily wrap this call to see what
files _forwardcopies is about to process.
"""
ma = a.manifest()
mb = b.manifest()
return mb.filesnotin(ma, match=match)
def usechangesetcentricalgo(repo):
"""Checks if we should use changeset-centric copy algorithms"""
if repo.filecopiesmode == b'changeset-sidedata':
return True
readfrom = repo.ui.config(b'experimental', b'copies.read-from')
changesetsource = (b'changeset-only', b'compatibility')
return readfrom in changesetsource
def _committedforwardcopies(a, b, base, match):
"""Like _forwardcopies(), but b.rev() cannot be None (working copy)"""
# files might have to be traced back to the fctx parent of the last
# one-side-only changeset, but not further back than that
repo = a._repo
if usechangesetcentricalgo(repo):
return _changesetforwardcopies(a, b, match)
debug = repo.ui.debugflag and repo.ui.configbool(b'devel', b'debug.copies')
dbg = repo.ui.debug
if debug:
dbg(b'debug.copies: looking into rename from %s to %s\n' % (a, b))
am = a.manifest()
basemf = None if base is None else base.manifest()
# find where new files came from
# we currently don't try to find where old files went, too expensive
# this means we can miss a case like 'hg rm b; hg cp a b'
cm = {}
# Computing the forward missing is quite expensive on large manifests, since
# it compares the entire manifests. We can optimize it in the common use
# case of computing what copies are in a commit versus its parent (like
# during a rebase or histedit). Note, we exclude merge commits from this
# optimization, since the ctx.files() for a merge commit is not correct for
# this comparison.
forwardmissingmatch = match
if b.p1() == a and b.p2().node() == node.nullid:
filesmatcher = matchmod.exact(b.files())
forwardmissingmatch = matchmod.intersectmatchers(match, filesmatcher)
missing = _computeforwardmissing(a, b, match=forwardmissingmatch)
ancestrycontext = a._repo.changelog.ancestors([b.rev()], inclusive=True)
if debug:
dbg(b'debug.copies: missing files to search: %d\n' % len(missing))
for f in sorted(missing):
if debug:
dbg(b'debug.copies: tracing file: %s\n' % f)
fctx = b[f]
fctx._ancestrycontext = ancestrycontext
if debug:
start = util.timer()
opath = _tracefile(fctx, am, basemf)
if opath:
if debug:
dbg(b'debug.copies: rename of: %s\n' % opath)
cm[f] = opath
if debug:
dbg(
b'debug.copies: time: %f seconds\n'
% (util.timer() - start)
)
return cm
def _revinfogetter(repo):
"""return a function that return multiple data given a <rev>"i
* p1: revision number of first parent
* p2: revision number of first parent
* p1copies: mapping of copies from p1
* p2copies: mapping of copies from p2
* removed: a list of removed files
"""
cl = repo.changelog
parents = cl.parentrevs
if repo.filecopiesmode == b'changeset-sidedata':
changelogrevision = cl.changelogrevision
flags = cl.flags
# A small cache to avoid doing the work twice for merges
#
# In the vast majority of cases, if we ask information for a revision
# about 1 parent, we'll later ask it for the other. So it make sense to
# keep the information around when reaching the first parent of a merge
# and dropping it after it was provided for the second parents.
#
# It exists cases were only one parent of the merge will be walked. It
# happens when the "destination" the copy tracing is descendant from a
# new root, not common with the "source". In that case, we will only walk
# through merge parents that are descendant of changesets common
# between "source" and "destination".
#
# With the current case implementation if such changesets have a copy
# information, we'll keep them in memory until the end of
# _changesetforwardcopies. We don't expect the case to be frequent
# enough to matters.
#
# In addition, it would be possible to reach pathological case, were
# many first parent are met before any second parent is reached. In
# that case the cache could grow. If this even become an issue one can
# safely introduce a maximum cache size. This would trade extra CPU/IO
# time to save memory.
merge_caches = {}
def revinfo(rev):
p1, p2 = parents(rev)
if flags(rev) & REVIDX_SIDEDATA:
e = merge_caches.pop(rev, None)
if e is not None:
return e
c = changelogrevision(rev)
p1copies = c.p1copies
p2copies = c.p2copies
removed = c.filesremoved
if p1 != node.nullrev and p2 != node.nullrev:
# XXX some case we over cache, IGNORE
merge_caches[rev] = (p1, p2, p1copies, p2copies, removed)
else:
p1copies = {}
p2copies = {}
removed = []
return p1, p2, p1copies, p2copies, removed
else:
def revinfo(rev):
p1, p2 = parents(rev)
ctx = repo[rev]
p1copies, p2copies = ctx._copies
removed = ctx.filesremoved()
return p1, p2, p1copies, p2copies, removed
return revinfo
def _changesetforwardcopies(a, b, match):
if a.rev() in (node.nullrev, b.rev()):
return {}
repo = a.repo().unfiltered()
children = {}
revinfo = _revinfogetter(repo)
cl = repo.changelog
missingrevs = cl.findmissingrevs(common=[a.rev()], heads=[b.rev()])
mrset = set(missingrevs)
roots = set()
for r in missingrevs:
for p in cl.parentrevs(r):
if p == node.nullrev:
continue
if p not in children:
children[p] = [r]
else:
children[p].append(r)
if p not in mrset:
roots.add(p)
if not roots:
# no common revision to track copies from
return {}
min_root = min(roots)
from_head = set(
cl.reachableroots(min_root, [b.rev()], list(roots), includepath=True)
)
iterrevs = set(from_head)
iterrevs &= mrset
iterrevs.update(roots)
iterrevs.remove(b.rev())
revs = sorted(iterrevs)
return _combinechangesetcopies(revs, children, b.rev(), revinfo, match)
def _combinechangesetcopies(revs, children, targetrev, revinfo, match):
"""combine the copies information for each item of iterrevs
revs: sorted iterable of revision to visit
children: a {parent: [children]} mapping.
targetrev: the final copies destination revision (not in iterrevs)
revinfo(rev): a function that return (p1, p2, p1copies, p2copies, removed)
match: a matcher
It returns the aggregated copies information for `targetrev`.
"""
all_copies = {}
alwaysmatch = match.always()
for r in revs:
copies = all_copies.pop(r, None)
if copies is None:
# this is a root
copies = {}
for i, c in enumerate(children[r]):
p1, p2, p1copies, p2copies, removed = revinfo(c)
if r == p1:
parent = 1
childcopies = p1copies
else:
assert r == p2
parent = 2
childcopies = p2copies
if not alwaysmatch:
childcopies = {
dst: src for dst, src in childcopies.items() if match(dst)
}
newcopies = copies
if childcopies:
newcopies = _chain(newcopies, childcopies)
# _chain makes a copies, we can avoid doing so in some
# simple/linear cases.
assert newcopies is not copies
for f in removed:
if f in newcopies:
if newcopies is copies:
# copy on write to avoid affecting potential other
# branches. when there are no other branches, this
# could be avoided.
newcopies = copies.copy()
del newcopies[f]
othercopies = all_copies.get(c)
if othercopies is None:
all_copies[c] = newcopies
else:
# we are the second parent to work on c, we need to merge our
# work with the other.
#
# Unlike when copies are stored in the filelog, we consider
# it a copy even if the destination already existed on the
# other branch. It's simply too expensive to check if the
# file existed in the manifest.
#
# In case of conflict, parent 1 take precedence over parent 2.
# This is an arbitrary choice made anew when implementing
# changeset based copies. It was made without regards with
# potential filelog related behavior.
if parent == 1:
othercopies.update(newcopies)
else:
newcopies.update(othercopies)
all_copies[c] = newcopies
return all_copies[targetrev]
def _forwardcopies(a, b, base=None, match=None):
"""find {dst@b: src@a} copy mapping where a is an ancestor of b"""
if base is None:
base = a
match = a.repo().narrowmatch(match)
# check for working copy
if b.rev() is None:
cm = _committedforwardcopies(a, b.p1(), base, match)
# combine copies from dirstate if necessary
copies = _chain(cm, _dirstatecopies(b._repo, match))
else:
copies = _committedforwardcopies(a, b, base, match)
return copies
def _backwardrenames(a, b, match):
if a._repo.ui.config(b'experimental', b'copytrace') == b'off':
return {}
# Even though we're not taking copies into account, 1:n rename situations
# can still exist (e.g. hg cp a b; hg mv a c). In those cases we
# arbitrarily pick one of the renames.
# We don't want to pass in "match" here, since that would filter
# the destination by it. Since we're reversing the copies, we want
# to filter the source instead.
f = _forwardcopies(b, a)
r = {}
for k, v in sorted(pycompat.iteritems(f)):
if match and not match(v):
continue
# remove copies
if v in a:
continue
r[v] = k
return r
def pathcopies(x, y, match=None):
"""find {dst@y: src@x} copy mapping for directed compare"""
repo = x._repo
debug = repo.ui.debugflag and repo.ui.configbool(b'devel', b'debug.copies')
if debug:
repo.ui.debug(
b'debug.copies: searching copies from %s to %s\n' % (x, y)
)
if x == y or not x or not y:
return {}
a = y.ancestor(x)
if a == x:
if debug:
repo.ui.debug(b'debug.copies: search mode: forward\n')
if y.rev() is None and x == y.p1():
# short-circuit to avoid issues with merge states
return _dirstatecopies(repo, match)
copies = _forwardcopies(x, y, match=match)
elif a == y:
if debug:
repo.ui.debug(b'debug.copies: search mode: backward\n')
copies = _backwardrenames(x, y, match=match)
else:
if debug:
repo.ui.debug(b'debug.copies: search mode: combined\n')
base = None
if a.rev() != node.nullrev:
base = x
copies = _chain(
_backwardrenames(x, a, match=match),
_forwardcopies(a, y, base, match=match),
)
_filter(x, y, copies)
return copies
def mergecopies(repo, c1, c2, base):
"""
Finds moves and copies between context c1 and c2 that are relevant for
merging. 'base' will be used as the merge base.
Copytracing is used in commands like rebase, merge, unshelve, etc to merge
files that were moved/ copied in one merge parent and modified in another.
For example:
o ---> 4 another commit
|
| o ---> 3 commit that modifies a.txt
| /
o / ---> 2 commit that moves a.txt to b.txt
|/
o ---> 1 merge base
If we try to rebase revision 3 on revision 4, since there is no a.txt in
revision 4, and if user have copytrace disabled, we prints the following
message:
```other changed <file> which local deleted```
Returns a tuple where:
"branch_copies" an instance of branch_copies.
"diverge" is a mapping of source name -> list of destination names
for divergent renames.
This function calls different copytracing algorithms based on config.
"""
# avoid silly behavior for update from empty dir
if not c1 or not c2 or c1 == c2:
return branch_copies(), branch_copies(), {}
narrowmatch = c1.repo().narrowmatch()
# avoid silly behavior for parent -> working dir
if c2.node() is None and c1.node() == repo.dirstate.p1():
return (
branch_copies(_dirstatecopies(repo, narrowmatch)),
branch_copies(),
{},
)
copytracing = repo.ui.config(b'experimental', b'copytrace')
if stringutil.parsebool(copytracing) is False:
# stringutil.parsebool() returns None when it is unable to parse the
# value, so we should rely on making sure copytracing is on such cases
return branch_copies(), branch_copies(), {}
if usechangesetcentricalgo(repo):
# The heuristics don't make sense when we need changeset-centric algos
return _fullcopytracing(repo, c1, c2, base)
# Copy trace disabling is explicitly below the node == p1 logic above
# because the logic above is required for a simple copy to be kept across a
# rebase.
if copytracing == b'heuristics':
# Do full copytracing if only non-public revisions are involved as
# that will be fast enough and will also cover the copies which could
# be missed by heuristics
if _isfullcopytraceable(repo, c1, base):
return _fullcopytracing(repo, c1, c2, base)
return _heuristicscopytracing(repo, c1, c2, base)
else:
return _fullcopytracing(repo, c1, c2, base)
def _isfullcopytraceable(repo, c1, base):
""" Checks that if base, source and destination are all no-public branches,
if yes let's use the full copytrace algorithm for increased capabilities
since it will be fast enough.
`experimental.copytrace.sourcecommitlimit` can be used to set a limit for
number of changesets from c1 to base such that if number of changesets are
more than the limit, full copytracing algorithm won't be used.
"""
if c1.rev() is None:
c1 = c1.p1()
if c1.mutable() and base.mutable():
sourcecommitlimit = repo.ui.configint(
b'experimental', b'copytrace.sourcecommitlimit'
)
commits = len(repo.revs(b'%d::%d', base.rev(), c1.rev()))
return commits < sourcecommitlimit
return False
def _checksinglesidecopies(
src, dsts1, m1, m2, mb, c2, base, copy, renamedelete
):
if src not in m2:
# deleted on side 2
if src not in m1:
# renamed on side 1, deleted on side 2
renamedelete[src] = dsts1
elif m2[src] != mb[src]:
if not _related(c2[src], base[src]):
return
# modified on side 2
for dst in dsts1:
if dst not in m2:
# dst not added on side 2 (handle as regular
# "both created" case in manifestmerge otherwise)
copy[dst] = src
class branch_copies(object):
"""Information about copies made on one side of a merge/graft.
"copy" is a mapping from destination name -> source name,
where source is in c1 and destination is in c2 or vice-versa.
"movewithdir" is a mapping from source name -> destination name,
where the file at source present in one context but not the other
needs to be moved to destination by the merge process, because the
other context moved the directory it is in.
"renamedelete" is a mapping of source name -> list of destination
names for files deleted in c1 that were renamed in c2 or vice-versa.
"dirmove" is a mapping of detected source dir -> destination dir renames.
This is needed for handling changes to new files previously grafted into
renamed directories.
"""
def __init__(
self, copy=None, renamedelete=None, dirmove=None, movewithdir=None
):
self.copy = {} if copy is None else copy
self.renamedelete = {} if renamedelete is None else renamedelete
self.dirmove = {} if dirmove is None else dirmove
self.movewithdir = {} if movewithdir is None else movewithdir
def _fullcopytracing(repo, c1, c2, base):
""" The full copytracing algorithm which finds all the new files that were
added from merge base up to the top commit and for each file it checks if
this file was copied from another file.
This is pretty slow when a lot of changesets are involved but will track all
the copies.
"""
m1 = c1.manifest()
m2 = c2.manifest()
mb = base.manifest()
copies1 = pathcopies(base, c1)
copies2 = pathcopies(base, c2)
if not (copies1 or copies2):
return branch_copies(), branch_copies(), {}
inversecopies1 = {}
inversecopies2 = {}
for dst, src in copies1.items():
inversecopies1.setdefault(src, []).append(dst)
for dst, src in copies2.items():
inversecopies2.setdefault(src, []).append(dst)
copy1 = {}
copy2 = {}
diverge = {}
renamedelete1 = {}
renamedelete2 = {}
allsources = set(inversecopies1) | set(inversecopies2)
for src in allsources:
dsts1 = inversecopies1.get(src)
dsts2 = inversecopies2.get(src)
if dsts1 and dsts2:
# copied/renamed on both sides
if src not in m1 and src not in m2:
# renamed on both sides
dsts1 = set(dsts1)
dsts2 = set(dsts2)
# If there's some overlap in the rename destinations, we
# consider it not divergent. For example, if side 1 copies 'a'
# to 'b' and 'c' and deletes 'a', and side 2 copies 'a' to 'c'
# and 'd' and deletes 'a'.
if dsts1 & dsts2:
for dst in dsts1 & dsts2:
copy1[dst] = src
copy2[dst] = src
else:
diverge[src] = sorted(dsts1 | dsts2)
elif src in m1 and src in m2:
# copied on both sides
dsts1 = set(dsts1)
dsts2 = set(dsts2)
for dst in dsts1 & dsts2:
copy1[dst] = src
copy2[dst] = src
# TODO: Handle cases where it was renamed on one side and copied
# on the other side
elif dsts1:
# copied/renamed only on side 1
_checksinglesidecopies(
src, dsts1, m1, m2, mb, c2, base, copy1, renamedelete1
)
elif dsts2:
# copied/renamed only on side 2
_checksinglesidecopies(
src, dsts2, m2, m1, mb, c1, base, copy2, renamedelete2
)
# find interesting file sets from manifests
addedinm1 = m1.filesnotin(mb, repo.narrowmatch())
addedinm2 = m2.filesnotin(mb, repo.narrowmatch())
u1 = sorted(addedinm1 - addedinm2)
u2 = sorted(addedinm2 - addedinm1)
header = b" unmatched files in %s"
if u1:
repo.ui.debug(b"%s:\n %s\n" % (header % b'local', b"\n ".join(u1)))
if u2:
repo.ui.debug(b"%s:\n %s\n" % (header % b'other', b"\n ".join(u2)))
if repo.ui.debugflag:
renamedeleteset = set()
divergeset = set()
for dsts in diverge.values():
divergeset.update(dsts)
for dsts in renamedelete1.values():
renamedeleteset.update(dsts)
for dsts in renamedelete2.values():
renamedeleteset.update(dsts)
repo.ui.debug(
b" all copies found (* = to merge, ! = divergent, "
b"% = renamed and deleted):\n"
)
for side, copies in ((b"local", copies1), (b"remote", copies2)):
if not copies:
continue
repo.ui.debug(b" on %s side:\n" % side)
for f in sorted(copies):
note = b""
if f in copy1 or f in copy2:
note += b"*"
if f in divergeset:
note += b"!"
if f in renamedeleteset:
note += b"%"
repo.ui.debug(
b" src: '%s' -> dst: '%s' %s\n" % (copies[f], f, note)
)
del renamedeleteset
del divergeset
repo.ui.debug(b" checking for directory renames\n")
dirmove1, movewithdir2 = _dir_renames(repo, c1, copy1, copies1, u2)
dirmove2, movewithdir1 = _dir_renames(repo, c2, copy2, copies2, u1)
branch_copies1 = branch_copies(copy1, renamedelete1, dirmove1, movewithdir1)
branch_copies2 = branch_copies(copy2, renamedelete2, dirmove2, movewithdir2)
return branch_copies1, branch_copies2, diverge
def _dir_renames(repo, ctx, copy, fullcopy, addedfiles):
"""Finds moved directories and files that should move with them.
ctx: the context for one of the sides
copy: files copied on the same side (as ctx)
fullcopy: files copied on the same side (as ctx), including those that
merge.manifestmerge() won't care about
addedfiles: added files on the other side (compared to ctx)
"""
# generate a directory move map
d = ctx.dirs()
invalid = set()
dirmove = {}
# examine each file copy for a potential directory move, which is
# when all the files in a directory are moved to a new directory
for dst, src in pycompat.iteritems(fullcopy):
dsrc, ddst = pathutil.dirname(src), pathutil.dirname(dst)
if dsrc in invalid:
# already seen to be uninteresting
continue
elif dsrc in d and ddst in d:
# directory wasn't entirely moved locally
invalid.add(dsrc)
elif dsrc in dirmove and dirmove[dsrc] != ddst:
# files from the same directory moved to two different places
invalid.add(dsrc)
else:
# looks good so far
dirmove[dsrc] = ddst
for i in invalid:
if i in dirmove:
del dirmove[i]
del d, invalid
if not dirmove:
return {}, {}
dirmove = {k + b"/": v + b"/" for k, v in pycompat.iteritems(dirmove)}
for d in dirmove:
repo.ui.debug(
b" discovered dir src: '%s' -> dst: '%s'\n" % (d, dirmove[d])
)
movewithdir = {}
# check unaccounted nonoverlapping files against directory moves
for f in addedfiles:
if f not in fullcopy:
for d in dirmove:
if f.startswith(d):
# new file added in a directory that was moved, move it
df = dirmove[d] + f[len(d) :]
if df not in copy:
movewithdir[f] = df
repo.ui.debug(
b" pending file src: '%s' -> dst: '%s'\n"
% (f, df)
)
break
return dirmove, movewithdir
def _heuristicscopytracing(repo, c1, c2, base):
""" Fast copytracing using filename heuristics
Assumes that moves or renames are of following two types:
1) Inside a directory only (same directory name but different filenames)
2) Move from one directory to another
(same filenames but different directory names)
Works only when there are no merge commits in the "source branch".
Source branch is commits from base up to c2 not including base.
If merge is involved it fallbacks to _fullcopytracing().
Can be used by setting the following config:
[experimental]
copytrace = heuristics
In some cases the copy/move candidates found by heuristics can be very large
in number and that will make the algorithm slow. The number of possible
candidates to check can be limited by using the config
`experimental.copytrace.movecandidateslimit` which defaults to 100.
"""
if c1.rev() is None:
c1 = c1.p1()
if c2.rev() is None:
c2 = c2.p1()
changedfiles = set()
m1 = c1.manifest()
if not repo.revs(b'%d::%d', base.rev(), c2.rev()):
# If base is not in c2 branch, we switch to fullcopytracing
repo.ui.debug(
b"switching to full copytracing as base is not "
b"an ancestor of c2\n"
)
return _fullcopytracing(repo, c1, c2, base)
ctx = c2
while ctx != base:
if len(ctx.parents()) == 2:
# To keep things simple let's not handle merges
repo.ui.debug(b"switching to full copytracing because of merges\n")
return _fullcopytracing(repo, c1, c2, base)
changedfiles.update(ctx.files())
ctx = ctx.p1()
copies2 = {}
cp = _forwardcopies(base, c2)
for dst, src in pycompat.iteritems(cp):
if src in m1:
copies2[dst] = src
# file is missing if it isn't present in the destination, but is present in
# the base and present in the source.
# Presence in the base is important to exclude added files, presence in the
# source is important to exclude removed files.
filt = lambda f: f not in m1 and f in base and f in c2
missingfiles = [f for f in changedfiles if filt(f)]
copies1 = {}
if missingfiles:
basenametofilename = collections.defaultdict(list)
dirnametofilename = collections.defaultdict(list)
for f in m1.filesnotin(base.manifest()):
basename = os.path.basename(f)
dirname = os.path.dirname(f)
basenametofilename[basename].append(f)
dirnametofilename[dirname].append(f)
for f in missingfiles:
basename = os.path.basename(f)
dirname = os.path.dirname(f)
samebasename = basenametofilename[basename]
samedirname = dirnametofilename[dirname]
movecandidates = samebasename + samedirname
# f is guaranteed to be present in c2, that's why
# c2.filectx(f) won't fail
f2 = c2.filectx(f)
# we can have a lot of candidates which can slow down the heuristics
# config value to limit the number of candidates moves to check
maxcandidates = repo.ui.configint(
b'experimental', b'copytrace.movecandidateslimit'
)
if len(movecandidates) > maxcandidates:
repo.ui.status(
_(
b"skipping copytracing for '%s', more "
b"candidates than the limit: %d\n"
)
% (f, len(movecandidates))
)
continue
for candidate in movecandidates:
f1 = c1.filectx(candidate)
if _related(f1, f2):
# if there are a few related copies then we'll merge
# changes into all of them. This matches the behaviour
# of upstream copytracing
copies1[candidate] = f
return branch_copies(copies1), branch_copies(copies2), {}
def _related(f1, f2):
"""return True if f1 and f2 filectx have a common ancestor
Walk back to common ancestor to see if the two files originate
from the same file. Since workingfilectx's rev() is None it messes
up the integer comparison logic, hence the pre-step check for
None (f1 and f2 can only be workingfilectx's initially).
"""
if f1 == f2:
return True # a match
g1, g2 = f1.ancestors(), f2.ancestors()
try:
f1r, f2r = f1.linkrev(), f2.linkrev()
if f1r is None:
f1 = next(g1)
if f2r is None:
f2 = next(g2)
while True:
f1r, f2r = f1.linkrev(), f2.linkrev()
if f1r > f2r:
f1 = next(g1)
elif f2r > f1r:
f2 = next(g2)
else: # f1 and f2 point to files in the same linkrev
return f1 == f2 # true if they point to the same file
except StopIteration:
return False
def graftcopies(wctx, ctx, base):
"""reproduce copies between base and ctx in the wctx
Unlike mergecopies(), this function will only consider copies between base
and ctx; it will ignore copies between base and wctx. Also unlike
mergecopies(), this function will apply copies to the working copy (instead
of just returning information about the copies). That makes it cheaper
(especially in the common case of base==ctx.p1()) and useful also when
experimental.copytrace=off.
merge.update() will have already marked most copies, but it will only
mark copies if it thinks the source files are related (see
merge._related()). It will also not mark copies if the file wasn't modified
on the local side. This function adds the copies that were "missed"
by merge.update().
"""
new_copies = pathcopies(base, ctx)
_filter(wctx.p1(), wctx, new_copies)
for dst, src in pycompat.iteritems(new_copies):
wctx[dst].markcopied(src)
def computechangesetfilesadded(ctx):
"""return the list of files added in a changeset
"""
added = []
for f in ctx.files():
if not any(f in p for p in ctx.parents()):
added.append(f)
return added
def computechangesetfilesremoved(ctx):
"""return the list of files removed in a changeset
"""
removed = []
for f in ctx.files():
if f not in ctx:
removed.append(f)
return removed
def computechangesetcopies(ctx):
"""return the copies data for a changeset
The copies data are returned as a pair of dictionnary (p1copies, p2copies).
Each dictionnary are in the form: `{newname: oldname}`
"""
p1copies = {}
p2copies = {}
p1 = ctx.p1()
p2 = ctx.p2()
narrowmatch = ctx._repo.narrowmatch()
for dst in ctx.files():
if not narrowmatch(dst) or dst not in ctx:
continue
copied = ctx[dst].renamed()
if not copied:
continue
src, srcnode = copied
if src in p1 and p1[src].filenode() == srcnode:
p1copies[dst] = src
elif src in p2 and p2[src].filenode() == srcnode:
p2copies[dst] = src
return p1copies, p2copies
def encodecopies(files, copies):
items = []
for i, dst in enumerate(files):
if dst in copies:
items.append(b'%d\0%s' % (i, copies[dst]))
if len(items) != len(copies):
raise error.ProgrammingError(
b'some copy targets missing from file list'
)
return b"\n".join(items)
def decodecopies(files, data):
try:
copies = {}
if not data:
return copies
for l in data.split(b'\n'):
strindex, src = l.split(b'\0')
i = int(strindex)
dst = files[i]
copies[dst] = src
return copies
except (ValueError, IndexError):
# Perhaps someone had chosen the same key name (e.g. "p1copies") and
# used different syntax for the value.
return None
def encodefileindices(files, subset):
subset = set(subset)
indices = []
for i, f in enumerate(files):
if f in subset:
indices.append(b'%d' % i)
return b'\n'.join(indices)
def decodefileindices(files, data):
try:
subset = []
if not data:
return subset
for strindex in data.split(b'\n'):
i = int(strindex)
if i < 0 or i >= len(files):
return None
subset.append(files[i])
return subset
except (ValueError, IndexError):
# Perhaps someone had chosen the same key name (e.g. "added") and
# used different syntax for the value.
return None
def _getsidedata(srcrepo, rev):
ctx = srcrepo[rev]
filescopies = computechangesetcopies(ctx)
filesadded = computechangesetfilesadded(ctx)
filesremoved = computechangesetfilesremoved(ctx)
sidedata = {}
if any([filescopies, filesadded, filesremoved]):
sortedfiles = sorted(ctx.files())
p1copies, p2copies = filescopies
p1copies = encodecopies(sortedfiles, p1copies)
p2copies = encodecopies(sortedfiles, p2copies)
filesadded = encodefileindices(sortedfiles, filesadded)
filesremoved = encodefileindices(sortedfiles, filesremoved)
if p1copies:
sidedata[sidedatamod.SD_P1COPIES] = p1copies
if p2copies:
sidedata[sidedatamod.SD_P2COPIES] = p2copies
if filesadded:
sidedata[sidedatamod.SD_FILESADDED] = filesadded
if filesremoved:
sidedata[sidedatamod.SD_FILESREMOVED] = filesremoved
return sidedata
def getsidedataadder(srcrepo, destrepo):
use_w = srcrepo.ui.configbool(b'experimental', b'worker.repository-upgrade')
if pycompat.iswindows or not use_w:
return _get_simple_sidedata_adder(srcrepo, destrepo)
else:
return _get_worker_sidedata_adder(srcrepo, destrepo)
def _sidedata_worker(srcrepo, revs_queue, sidedata_queue, tokens):
"""The function used by worker precomputing sidedata
It read an input queue containing revision numbers
It write in an output queue containing (rev, <sidedata-map>)
The `None` input value is used as a stop signal.
The `tokens` semaphore is user to avoid having too many unprocessed
entries. The workers needs to acquire one token before fetching a task.
They will be released by the consumer of the produced data.
"""
tokens.acquire()
rev = revs_queue.get()
while rev is not None:
data = _getsidedata(srcrepo, rev)
sidedata_queue.put((rev, data))
tokens.acquire()
rev = revs_queue.get()
# processing of `None` is completed, release the token.
tokens.release()
BUFF_PER_WORKER = 50
def _get_worker_sidedata_adder(srcrepo, destrepo):
"""The parallel version of the sidedata computation
This code spawn a pool of worker that precompute a buffer of sidedata
before we actually need them"""
# avoid circular import copies -> scmutil -> worker -> copies
from . import worker
nbworkers = worker._numworkers(srcrepo.ui)
tokens = multiprocessing.BoundedSemaphore(nbworkers * BUFF_PER_WORKER)
revsq = multiprocessing.Queue()
sidedataq = multiprocessing.Queue()
assert srcrepo.filtername is None
# queue all tasks beforehand, revision numbers are small and it make
# synchronisation simpler
#
# Since the computation for each node can be quite expensive, the overhead
# of using a single queue is not revelant. In practice, most computation
# are fast but some are very expensive and dominate all the other smaller
# cost.
for r in srcrepo.changelog.revs():
revsq.put(r)
# queue the "no more tasks" markers
for i in range(nbworkers):
revsq.put(None)
allworkers = []
for i in range(nbworkers):
args = (srcrepo, revsq, sidedataq, tokens)
w = multiprocessing.Process(target=_sidedata_worker, args=args)
allworkers.append(w)
w.start()
# dictionnary to store results for revision higher than we one we are
# looking for. For example, if we need the sidedatamap for 42, and 43 is
# received, when shelve 43 for later use.
staging = {}
def sidedata_companion(revlog, rev):
sidedata = {}
if util.safehasattr(revlog, b'filteredrevs'): # this is a changelog
# Is the data previously shelved ?
sidedata = staging.pop(rev, None)
if sidedata is None:
# look at the queued result until we find the one we are lookig
# for (shelve the other ones)
r, sidedata = sidedataq.get()
while r != rev:
staging[r] = sidedata
r, sidedata = sidedataq.get()
tokens.release()
return False, (), sidedata
return sidedata_companion
def _get_simple_sidedata_adder(srcrepo, destrepo):
"""The simple version of the sidedata computation
It just compute it in the same thread on request"""
def sidedatacompanion(revlog, rev):
sidedata = {}
if util.safehasattr(revlog, 'filteredrevs'): # this is a changelog
sidedata = _getsidedata(srcrepo, rev)
return False, (), sidedata
return sidedatacompanion
def getsidedataremover(srcrepo, destrepo):
def sidedatacompanion(revlog, rev):
f = ()
if util.safehasattr(revlog, 'filteredrevs'): # this is a changelog
if revlog.flags(rev) & REVIDX_SIDEDATA:
f = (
sidedatamod.SD_P1COPIES,
sidedatamod.SD_P2COPIES,
sidedatamod.SD_FILESADDED,
sidedatamod.SD_FILESREMOVED,
)
return False, f, {}
return sidedatacompanion