mercurial/similar.py
author FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
Wed, 05 Nov 2014 23:24:47 +0900
changeset 23183 51c9196a6bd0
parent 16683 525fdb738975
child 27359 a56c47ed3885
permissions -rw-r--r--
largefiles: remove meaningless code path for "hg pull --rebase" This patch removes "--rebase" specific code path for "hg pull" in "overridepull", because previous patch makes it meaningless: now, "rebase.rebase" ("orig" invocation in this patch) can update/commit largefiles safely without "repo._isrebasing = True". As a side effect of removing "rebase.rebase" invocation in "overridepull", this patch removes "nothing to rebase ..." message in "test-largefiles.t", which is shown only when rebase extension is enabled AFTER largefiles: before this patch: 1. "dispatch" invokes "pullrebase" of rebase as "hg pull" at first, because rebase wraps "hg pull" later 2. "pullrebase" invokes "overridepull" of largefiles as "orig", even though rebase assumes that "orig" is "pull" of commands 3. "overridepull" executes "pull" and "rebase" directly 3.1 "pull" pulls changesets and creates new head "X" 3.2 "rebase" rebases current working parent "Y" on "X" 4. "overridepull" returns to "pullrebase" 5. "pullrebase" tries to rebase, but there is nothing to be done, because "Y" is already rebased on "X". then, it shows "nothing to rebase ..." after this patch: 1. "dispatch" invokes "pullrebase" of rebase as "hg pull" 2. "pullrebase" invokes "overridepull" of largefiles as "orig" 3. "overridepull" executes "pull" as "orig" 4. "overridepull" returns to "pullrebase" 5. revision "Y" is not yet rebased, so "pullrebase" doesn't shows "nothing to rebase ..." As another side effect of removing "rebase.rebase" invocation, this patch fixes issue3861, which occurs only when rebase extension is enabled BEFORE largefiles: before this patch: 1. "dispatch" invokes "overridepull" of largefiles at first, because largefiles wrap "hg pull" later 2. "overridepull" executes "pull" and "rebase" explicitly 2.1 "pull" pulls changesets and creates new head "X" 2.2 "rebase" rebases current working parent, but fails because no revision is checked out in issue3861 case 3. "overridepull" returns to "dispatch" with exit code 1 returned from "rebase" at (2.2) 4. "hg pull" terminates with exit code 1 unexpectedly after this patch: 1. "dispatch" invokes "overridepull" of largefiles at first 2. "overridepull" invokes "pullrebase" of rebase as "orig" 3. "pullrebase" invokes "pull" as "orig" 4. "pullrebase" invokes "rebase", and it fails 5. "pullrebase" returns to "overridepull" with exit code 0 (because "pullrebase" ignores result of "pull" and "rebase") 6. "overridepull" returns to "dispatch" with exit code 0 returned from "rebase" at (5) 7. "hg pull" terminates with exit code 0

# similar.py - mechanisms for finding similar files
#
# Copyright 2005-2007 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 i18n import _
import util
import mdiff
import bdiff

def _findexactmatches(repo, added, removed):
    '''find renamed files that have no changes

    Takes a list of new filectxs and a list of removed filectxs, and yields
    (before, after) tuples of exact matches.
    '''
    numfiles = len(added) + len(removed)

    # Get hashes of removed files.
    hashes = {}
    for i, fctx in enumerate(removed):
        repo.ui.progress(_('searching for exact renames'), i, total=numfiles)
        h = util.sha1(fctx.data()).digest()
        hashes[h] = fctx

    # For each added file, see if it corresponds to a removed file.
    for i, fctx in enumerate(added):
        repo.ui.progress(_('searching for exact renames'), i + len(removed),
                total=numfiles)
        h = util.sha1(fctx.data()).digest()
        if h in hashes:
            yield (hashes[h], fctx)

    # Done
    repo.ui.progress(_('searching for exact renames'), None)

def _findsimilarmatches(repo, added, removed, threshold):
    '''find potentially renamed files based on similar file content

    Takes a list of new filectxs and a list of removed filectxs, and yields
    (before, after, score) tuples of partial matches.
    '''
    copies = {}
    for i, r in enumerate(removed):
        repo.ui.progress(_('searching for similar files'), i,
                         total=len(removed))

        # lazily load text
        @util.cachefunc
        def data():
            orig = r.data()
            return orig, mdiff.splitnewlines(orig)

        def score(text):
            orig, lines = data()
            # bdiff.blocks() returns blocks of matching lines
            # count the number of bytes in each
            equal = 0
            matches = bdiff.blocks(text, orig)
            for x1, x2, y1, y2 in matches:
                for line in lines[y1:y2]:
                    equal += len(line)

            lengths = len(text) + len(orig)
            return equal * 2.0 / lengths

        for a in added:
            bestscore = copies.get(a, (None, threshold))[1]
            myscore = score(a.data())
            if myscore >= bestscore:
                copies[a] = (r, myscore)
    repo.ui.progress(_('searching'), None)

    for dest, v in copies.iteritems():
        source, score = v
        yield source, dest, score

def findrenames(repo, added, removed, threshold):
    '''find renamed files -- yields (before, after, score) tuples'''
    parentctx = repo['.']
    workingctx = repo[None]

    # Zero length files will be frequently unrelated to each other, and
    # tracking the deletion/addition of such a file will probably cause more
    # harm than good. We strip them out here to avoid matching them later on.
    addedfiles = set([workingctx[fp] for fp in added
            if workingctx[fp].size() > 0])
    removedfiles = set([parentctx[fp] for fp in removed
            if fp in parentctx and parentctx[fp].size() > 0])

    # Find exact matches.
    for (a, b) in _findexactmatches(repo,
            sorted(addedfiles), sorted(removedfiles)):
        addedfiles.remove(b)
        yield (a.path(), b.path(), 1.0)

    # If the user requested similar files to be matched, search for them also.
    if threshold < 1.0:
        for (a, b, score) in _findsimilarmatches(repo,
                sorted(addedfiles), sorted(removedfiles), threshold):
            yield (a.path(), b.path(), score)