repair: add experimental option to write bundle2 files

This adds an experimental option 'strip-bundle2-version' which causes backup
bundles to use bundle2 formatting.  Especially for generaldelta repositories,
this should provide significant performance gains for any operation that needs
to write a backup.

mercurial/repair.py

@@ -1,197 +1,216 b''
 # repair.py - functions for repository repair for mercurial
 #
 # Copyright 2005, 2006 Chris Mason <[e-mail]>
 # Copyright 2007 Matt Mackall
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
-from mercurial import changegroup, exchange, util
+from mercurial import changegroup, exchange, util, bundle2
 from mercurial.node import short, hex
 from mercurial.i18n import _
 import errno
 
 def _bundle(repo, bases, heads, node, suffix, compress=True):
     """create a bundle with the specified revisions as a backup"""
-    cg = changegroup.changegroupsubset(repo, bases, heads, 'strip')
+    usebundle2 = (repo.ui.config('experimental', 'bundle2-exp') and
+                  repo.ui.config('experimental', 'strip-bundle2-version'))
+    if usebundle2:
+        cgversion = repo.ui.config('experimental', 'strip-bundle2-version')
+    else:
+        cgversion = '01'
+
+    cg = changegroup.changegroupsubset(repo, bases, heads, 'strip',
+                                       version=cgversion)
     backupdir = "strip-backup"
     vfs = repo.vfs
     if not vfs.isdir(backupdir):
         vfs.mkdir(backupdir)
 
     # Include a hash of all the nodes in the filename for uniqueness
     hexbases = (hex(n) for n in bases)
     hexheads = (hex(n) for n in heads)
     allcommits = repo.set('%ls::%ls', hexbases, hexheads)
     allhashes = sorted(c.hex() for c in allcommits)
     totalhash = util.sha1(''.join(allhashes)).hexdigest()
     name = "%s/%s-%s-%s.hg" % (backupdir, short(node), totalhash[:8], suffix)
 
-    if compress:
+    if usebundle2:
+        bundletype = "HG2Y"
+    elif compress:
         bundletype = "HG10BZ"
     else:
         bundletype = "HG10UN"
     return changegroup.writebundle(repo.ui, cg, name, bundletype, vfs)
 
 def _collectfiles(repo, striprev):
     """find out the filelogs affected by the strip"""
     files = set()
 
     for x in xrange(striprev, len(repo)):
         files.update(repo[x].files())
 
     return sorted(files)
 
 def _collectbrokencsets(repo, files, striprev):
     """return the changesets which will be broken by the truncation"""
     s = set()
     def collectone(revlog):
         _, brokenset = revlog.getstrippoint(striprev)
         s.update([revlog.linkrev(r) for r in brokenset])
 
     collectone(repo.manifest)
     for fname in files:
         collectone(repo.file(fname))
 
     return s
 
 def strip(ui, repo, nodelist, backup=True, topic='backup'):
 
     # Simple way to maintain backwards compatibility for this
     # argument.
     if backup in ['none', 'strip']:
         backup = False
 
     repo = repo.unfiltered()
     repo.destroying()
 
     cl = repo.changelog
     # TODO handle undo of merge sets
     if isinstance(nodelist, str):
         nodelist = [nodelist]
     striplist = [cl.rev(node) for node in nodelist]
     striprev = min(striplist)
 
     # Some revisions with rev > striprev may not be descendants of striprev.
     # We have to find these revisions and put them in a bundle, so that
     # we can restore them after the truncations.
     # To create the bundle we use repo.changegroupsubset which requires
     # the list of heads and bases of the set of interesting revisions.
     # (head = revision in the set that has no descendant in the set;
     #  base = revision in the set that has no ancestor in the set)
     tostrip = set(striplist)
     for rev in striplist:
         for desc in cl.descendants([rev]):
             tostrip.add(desc)
 
     files = _collectfiles(repo, striprev)
     saverevs = _collectbrokencsets(repo, files, striprev)
 
     # compute heads
     saveheads = set(saverevs)
     for r in xrange(striprev + 1, len(cl)):
         if r not in tostrip:
             saverevs.add(r)
             saveheads.difference_update(cl.parentrevs(r))
             saveheads.add(r)
     saveheads = [cl.node(r) for r in saveheads]
 
     # compute base nodes
     if saverevs:
         descendants = set(cl.descendants(saverevs))
         saverevs.difference_update(descendants)
     savebases = [cl.node(r) for r in saverevs]
     stripbases = [cl.node(r) for r in tostrip]
 
     # For a set s, max(parents(s) - s) is the same as max(heads(::s - s)), but
     # is much faster
     newbmtarget = repo.revs('max(parents(%ld) - (%ld))', tostrip, tostrip)
     if newbmtarget:
         newbmtarget = repo[newbmtarget.first()].node()
     else:
         newbmtarget = '.'
 
     bm = repo._bookmarks
     updatebm = []
     for m in bm:
         rev = repo[bm[m]].rev()
         if rev in tostrip:
             updatebm.append(m)
 
     # create a changegroup for all the branches we need to keep
     backupfile = None
     vfs = repo.vfs
     if backup:
         backupfile = _bundle(repo, stripbases, cl.heads(), node, topic)
         repo.ui.status(_("saved backup bundle to %s\n") %
                        vfs.join(backupfile))
         repo.ui.log("backupbundle", "saved backup bundle to %s\n",
                     vfs.join(backupfile))
     if saveheads or savebases:
         # do not compress partial bundle if we remove it from disk later
         chgrpfile = _bundle(repo, savebases, saveheads, node, 'temp',
                             compress=False)
 
     mfst = repo.manifest
 
     tr = repo.transaction("strip")
     offset = len(tr.entries)
 
     try:
         tr.startgroup()
         cl.strip(striprev, tr)
         mfst.strip(striprev, tr)
         for fn in files:
             repo.file(fn).strip(striprev, tr)
         tr.endgroup()
 
         try:
             for i in xrange(offset, len(tr.entries)):
                 file, troffset, ignore = tr.entries[i]
                 repo.svfs(file, 'a').truncate(troffset)
                 if troffset == 0:
                     repo.store.markremoved(file)
             tr.close()
         except: # re-raises
             tr.abort()
             raise
 
         if saveheads or savebases:
             ui.note(_("adding branch\n"))
             f = vfs.open(chgrpfile, "rb")
             gen = exchange.readbundle(ui, f, chgrpfile, vfs)
             if not repo.ui.verbose:
                 # silence internal shuffling chatter
                 repo.ui.pushbuffer()
-            changegroup.addchangegroup(repo, gen, 'strip',
-                                       'bundle:' + vfs.join(chgrpfile), True)
+            if isinstance(gen, bundle2.unbundle20):
+                tr = repo.transaction('strip')
+                try:
+                    bundle2.processbundle(repo, gen, lambda: tr)
+                    tr.close()
+                finally:
+                    tr.release()
+            else:
+                changegroup.addchangegroup(repo, gen, 'strip',
+                                           'bundle:' + vfs.join(chgrpfile),
+                                           True)
             if not repo.ui.verbose:
                 repo.ui.popbuffer()
             f.close()
 
         # remove undo files
         for undovfs, undofile in repo.undofiles():
             try:
                 undovfs.unlink(undofile)
             except OSError, e:
                 if e.errno != errno.ENOENT:
                     ui.warn(_('error removing %s: %s\n') %
                             (undovfs.join(undofile), str(e)))
 
         for m in updatebm:
             bm[m] = repo[newbmtarget].node()
         bm.write()
     except: # re-raises
         if backupfile:
             ui.warn(_("strip failed, full bundle stored in '%s'\n")
                     % vfs.join(backupfile))
         elif saveheads:
             ui.warn(_("strip failed, partial bundle stored in '%s'\n")
                     % vfs.join(chgrpfile))
         raise
     else:
         if saveheads or savebases:
             # Remove partial backup only if there were no exceptions
             vfs.unlink(chgrpfile)
 
     repo.destroyed()

tests/test-strip.t

@@ -1,571 +1,595 b''
   $ echo "[extensions]" >> $HGRCPATH
   $ echo "strip=" >> $HGRCPATH
 
   $ restore() {
   >     hg unbundle -q .hg/strip-backup/*
   >     rm .hg/strip-backup/*
   > }
   $ teststrip() {
   >     hg up -C $1
   >     echo % before update $1, strip $2
   >     hg parents
   >     hg --traceback strip $2
   >     echo % after update $1, strip $2
   >     hg parents
   >     restore
   > }
 
   $ hg init test
   $ cd test
 
   $ echo foo > bar
   $ hg ci -Ama
   adding bar
 
   $ echo more >> bar
   $ hg ci -Amb
 
   $ echo blah >> bar
   $ hg ci -Amc
 
   $ hg up 1
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo blah >> bar
   $ hg ci -Amd
   created new head
 
   $ echo final >> bar
   $ hg ci -Ame
 
   $ hg log
   changeset:   4:443431ffac4f
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     e
   
   changeset:   3:65bd5f99a4a3
   parent:      1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     d
   
   changeset:   2:264128213d29
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     c
   
   changeset:   1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     b
   
   changeset:   0:9ab35a2d17cb
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     a
   
 
   $ teststrip 4 4
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   % before update 4, strip 4
   changeset:   4:443431ffac4f
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     e
   
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   % after update 4, strip 4
   changeset:   3:65bd5f99a4a3
   tag:         tip
   parent:      1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     d
   
   $ teststrip 4 3
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   % before update 4, strip 3
   changeset:   4:443431ffac4f
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     e
   
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   % after update 4, strip 3
   changeset:   1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     b
   
   $ teststrip 1 4
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   % before update 1, strip 4
   changeset:   1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     b
   
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   % after update 1, strip 4
   changeset:   1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     b
   
   $ teststrip 4 2
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   % before update 4, strip 2
   changeset:   4:443431ffac4f
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     e
   
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   % after update 4, strip 2
   changeset:   3:443431ffac4f
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     e
   
   $ teststrip 4 1
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   % before update 4, strip 1
   changeset:   4:264128213d29
   tag:         tip
   parent:      1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     c
   
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   % after update 4, strip 1
   changeset:   0:9ab35a2d17cb
   tag:         tip
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     a
   
   $ teststrip null 4
   0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   % before update null, strip 4
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   % after update null, strip 4
 
   $ hg log
   changeset:   4:264128213d29
   tag:         tip
   parent:      1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     c
   
   changeset:   3:443431ffac4f
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     e
   
   changeset:   2:65bd5f99a4a3
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     d
   
   changeset:   1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     b
   
   changeset:   0:9ab35a2d17cb
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     a
   
+  $ hg up -C 4
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  $ hg parents
+  changeset:   4:264128213d29
+  tag:         tip
+  parent:      1:ef3a871183d7
+  user:        test
+  date:        Thu Jan 01 00:00:00 1970 +0000
+  summary:     c
+  
+  $ hg --config experimental.bundle2-exp=True --config experimental.strip-bundle2-version=02 --traceback strip 4
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  saved backup bundle to $TESTTMP/test/.hg/strip-backup/264128213d29-0b39d6bf-backup.hg (glob)
+  $ hg parents
+  changeset:   1:ef3a871183d7
+  user:        test
+  date:        Thu Jan 01 00:00:00 1970 +0000
+  summary:     b
+  
+  $ hg debugbundle .hg/strip-backup/*
+  Stream params: {}
+  b2x:changegroup -- "{'version': '02'}"
+      264128213d290d868c54642d13aeaa3675551a78
+  $ restore
 
   $ hg up -C 2
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg merge 4
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   (branch merge, don't forget to commit)
 
 before strip of merge parent
 
   $ hg parents
   changeset:   2:65bd5f99a4a3
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     d
   
   changeset:   4:264128213d29
   tag:         tip
   parent:      1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     c
   
   $ hg strip 4
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
 
 after strip of merge parent
 
   $ hg parents
   changeset:   1:ef3a871183d7
   user:        test
   date:        Thu Jan 01 00:00:00 1970 +0000
   summary:     b
   
   $ restore
 
   $ hg up
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ hg log -G
   @  changeset:   4:264128213d29
   |  tag:         tip
   |  parent:      1:ef3a871183d7
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     c
   |
   | o  changeset:   3:443431ffac4f
   | |  user:        test
   | |  date:        Thu Jan 01 00:00:00 1970 +0000
   | |  summary:     e
   | |
   | o  changeset:   2:65bd5f99a4a3
   |/   user:        test
   |    date:        Thu Jan 01 00:00:00 1970 +0000
   |    summary:     d
   |
   o  changeset:   1:ef3a871183d7
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     b
   |
   o  changeset:   0:9ab35a2d17cb
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
 
 2 is parent of 3, only one strip should happen
 
   $ hg strip "roots(2)" 3
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   $ hg log -G
   @  changeset:   2:264128213d29
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     c
   |
   o  changeset:   1:ef3a871183d7
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     b
   |
   o  changeset:   0:9ab35a2d17cb
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
   $ restore
   $ hg log -G
   o  changeset:   4:443431ffac4f
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     e
   |
   o  changeset:   3:65bd5f99a4a3
   |  parent:      1:ef3a871183d7
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     d
   |
   | @  changeset:   2:264128213d29
   |/   user:        test
   |    date:        Thu Jan 01 00:00:00 1970 +0000
   |    summary:     c
   |
   o  changeset:   1:ef3a871183d7
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     b
   |
   o  changeset:   0:9ab35a2d17cb
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
 
 2 different branches: 2 strips
 
   $ hg strip 2 4
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   $ hg log -G
   o  changeset:   2:65bd5f99a4a3
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     d
   |
   @  changeset:   1:ef3a871183d7
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     b
   |
   o  changeset:   0:9ab35a2d17cb
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
   $ restore
 
 2 different branches and a common ancestor: 1 strip
 
   $ hg strip 1 "2|4"
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   $ restore
 
 verify fncache is kept up-to-date
 
   $ touch a
   $ hg ci -qAm a
   $ cat .hg/store/fncache | sort
   data/a.i
   data/bar.i
   $ hg strip tip
   0 files updated, 0 files merged, 1 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   $ cat .hg/store/fncache
   data/bar.i
 
 stripping an empty revset
 
   $ hg strip "1 and not 1"
   abort: empty revision set
   [255]
 
 remove branchy history for qimport tests
 
   $ hg strip 3
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
 
 
 strip of applied mq should cleanup status file
 
   $ echo "mq=" >> $HGRCPATH
   $ hg up -C 3
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ echo fooagain >> bar
   $ hg ci -mf
   $ hg qimport -r tip:2
 
 applied patches before strip
 
   $ hg qapplied
   2.diff
   3.diff
   4.diff
 
 stripping revision in queue
 
   $ hg strip 3
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
 
 applied patches after stripping rev in queue
 
   $ hg qapplied
   2.diff
 
 stripping ancestor of queue
 
   $ hg strip 1
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
 
 applied patches after stripping ancestor of queue
 
   $ hg qapplied
 
 Verify strip protects against stripping wc parent when there are uncommitted mods
 
   $ echo b > b
   $ hg add b
   $ hg ci -m 'b'
   $ hg log --graph
   @  changeset:   1:7519abd79d14
   |  tag:         tip
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     b
   |
   o  changeset:   0:9ab35a2d17cb
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
 
   $ echo c > b
   $ echo c > bar
   $ hg strip tip
   abort: local changes found
   [255]
   $ hg strip tip --keep
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   $ hg log --graph
   @  changeset:   0:9ab35a2d17cb
      tag:         tip
      user:        test
      date:        Thu Jan 01 00:00:00 1970 +0000
      summary:     a
   
   $ hg status
   M bar
   ? b
 
 Strip adds, removes, modifies with --keep
 
   $ touch b
   $ hg add b
   $ hg commit -mb
   $ touch c
 
 ... with a clean working dir
 
   $ hg add c
   $ hg rm bar
   $ hg commit -mc
   $ hg status
   $ hg strip --keep tip
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/*-backup.hg (glob)
   $ hg status
   ! bar
   ? c
 
 ... with a dirty working dir
 
   $ hg add c
   $ hg rm bar
   $ hg commit -mc
   $ hg status
   $ echo b > b
   $ echo d > d
   $ hg strip --keep tip
   saved backup bundle to $TESTTMP/test/.hg/strip-backup/57e364c8a475-4cfed93c-backup.hg (glob)
   $ hg status
   M b
   ! bar
   ? c
   ? d
   $ cd ..
 
 stripping many nodes on a complex graph (issue3299)
 
   $ hg init issue3299
   $ cd issue3299
   $ hg debugbuilddag '@a.:a@b.:b.:x<a@a.:a<b@b.:b<a@a.:a'
   $ hg strip 'not ancestors(x)'
   saved backup bundle to $TESTTMP/issue3299/.hg/strip-backup/*-backup.hg (glob)
 
 test hg strip -B bookmark
 
   $ cd ..
   $ hg init bookmarks
   $ cd bookmarks
   $ hg debugbuilddag '..<2.*1/2:m<2+3:c<m+3:a<2.:b'
   $ hg bookmark -r 'a' 'todelete'
   $ hg bookmark -r 'b' 'B'
   $ hg bookmark -r 'b' 'nostrip'
   $ hg bookmark -r 'c' 'delete'
   $ hg up -C todelete
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   (activating bookmark todelete)
   $ hg strip -B nostrip
   bookmark 'nostrip' deleted
   abort: empty revision set
   [255]
   $ hg strip -B todelete
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/bookmarks/.hg/strip-backup/*-backup.hg (glob)
   bookmark 'todelete' deleted
   $ hg id -ir dcbb326fdec2
   abort: unknown revision 'dcbb326fdec2'!
   [255]
   $ hg id -ir d62d843c9a01
   d62d843c9a01
   $ hg bookmarks
      B                         9:ff43616e5d0f
      delete                    6:2702dd0c91e7
   $ hg strip -B delete
   saved backup bundle to $TESTTMP/bookmarks/.hg/strip-backup/*-backup.hg (glob)
   bookmark 'delete' deleted
   $ hg id -ir 6:2702dd0c91e7
   abort: unknown revision '2702dd0c91e7'!
   [255]
   $ hg update B
   0 files updated, 0 files merged, 0 files removed, 0 files unresolved
   (activating bookmark B)
   $ echo a > a
   $ hg add a
   $ hg strip -B B
   abort: local changes found
   [255]
   $ hg bookmarks
    * B                         6:ff43616e5d0f
 
 Make sure no one adds back a -b option:
 
   $ hg strip -b tip
   hg strip: option -b not recognized
   hg strip [-k] [-f] [-n] [-B bookmark] [-r] REV...
   
   strip changesets and all their descendants from the repository
   
   (use "hg help -e strip" to show help for the strip extension)
   
   options ([+] can be repeated):
   
    -r --rev REV [+]    strip specified revision (optional, can specify revisions
                        without this option)
    -f --force          force removal of changesets, discard uncommitted changes
                        (no backup)
       --no-backup      no backups
    -k --keep           do not modify working copy during strip
    -B --bookmark VALUE remove revs only reachable from given bookmark
       --mq             operate on patch repository
   
   (use "hg strip -h" to show more help)
   [255]
 
   $ cd ..
 
 Verify bundles don't get overwritten:
 
   $ hg init doublebundle
   $ cd doublebundle
   $ touch a
   $ hg commit -Aqm a
   $ touch b
   $ hg commit -Aqm b
   $ hg strip -r 0
   0 files updated, 0 files merged, 2 files removed, 0 files unresolved
   saved backup bundle to $TESTTMP/doublebundle/.hg/strip-backup/3903775176ed-e68910bd-backup.hg (glob)
   $ ls .hg/strip-backup
   3903775176ed-e68910bd-backup.hg
   $ hg pull -q -r 3903775176ed .hg/strip-backup/3903775176ed-e68910bd-backup.hg
   $ hg strip -r 0
   saved backup bundle to $TESTTMP/doublebundle/.hg/strip-backup/3903775176ed-54390173-backup.hg (glob)
   $ ls .hg/strip-backup
   3903775176ed-54390173-backup.hg
   3903775176ed-e68910bd-backup.hg