Handle merge with deletions
If you merge with a repo that has deleted a file after editing it, hg
attempted to resolve the file. This (correctly) resulted in hg verify
errors because the resolved version didn't show up in the manifests.
This moves the manifest resolution before file resolution and decides
which files to resolve based on the (partially) resolved manifest.
After files are resolved, the final manifest is committed.
# transaction.py - simple journalling scheme for mercurial
#
# This transaction scheme is intended to gracefully handle program
# errors and interruptions. More serious failures like system crashes
# can be recovered with an fsck-like tool. As the whole repository is
# effectively log-structured, this should amount to simply truncating
# anything that isn't referenced in the changelog.
#
# Copyright 2005 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
import os
class transaction:
def __init__(self, opener, journal, after = None):
self.opener = opener
self.after = after
self.entries = []
self.map = {}
self.journal = journal
# abort here if the journal already exists
if os.path.exists(self.journal):
raise "journal already exists!"
self.file = open(self.journal, "w")
def __del__(self):
if self.entries: self.abort()
try: os.unlink(self.journal)
except: pass
def add(self, file, offset):
if file in self.map: return
self.entries.append((file, offset))
self.map[file] = 1
# add enough data to the journal to do the truncate
self.file.write("%s\0%d\n" % (file, offset))
self.file.flush()
def close(self):
self.file.close()
self.entries = []
if self.after:
os.rename(self.journal, self.after)
else:
os.unlink(self.journal)
def abort(self):
if not self.entries: return
print "transaction abort!"
for f, o in self.entries:
try:
self.opener(f, "a").truncate(o)
except:
print "failed to truncate", f
self.entries = []
print "rollback completed"
def recover(self):
for l in open(self.journal).readlines():
f, o = l.split('\0')
self.opener(f, "a").truncate(int(o))
os.unlink(self.journal)