--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mercurial/destutil.py Tue Oct 20 15:59:10 2015 -0500
@@ -0,0 +1,200 @@
+# destutil.py - Mercurial utility function for command destination
+#
+# Copyright Matt Mackall <mpm@selenic.com> and other
+#
+# 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 _
+from . import (
+ bookmarks,
+ error,
+ obsolete,
+)
+
+def _destupdatevalidate(repo, rev, clean, check):
+ """validate that the destination comply to various rules
+
+ This exists as its own function to help wrapping from extensions."""
+ wc = repo[None]
+ p1 = wc.p1()
+ if not clean:
+ # Check that the update is linear.
+ #
+ # Mercurial do not allow update-merge for non linear pattern
+ # (that would be technically possible but was considered too confusing
+ # for user a long time ago)
+ #
+ # See mercurial.merge.update for details
+ if p1.rev() not in repo.changelog.ancestors([rev], inclusive=True):
+ dirty = wc.dirty(missing=True)
+ foreground = obsolete.foreground(repo, [p1.node()])
+ if not repo[rev].node() in foreground:
+ if dirty:
+ msg = _("uncommitted changes")
+ hint = _("commit and merge, or update --clean to"
+ " discard changes")
+ raise error.UpdateAbort(msg, hint=hint)
+ elif not check: # destination is not a descendant.
+ msg = _("not a linear update")
+ hint = _("merge or update --check to force update")
+ raise error.UpdateAbort(msg, hint=hint)
+
+def _destupdateobs(repo, clean, check):
+ """decide of an update destination from obsolescence markers"""
+ node = None
+ wc = repo[None]
+ p1 = wc.p1()
+ movemark = None
+
+ if p1.obsolete() and not p1.children():
+ # allow updating to successors
+ successors = obsolete.successorssets(repo, p1.node())
+
+ # behavior of certain cases is as follows,
+ #
+ # divergent changesets: update to highest rev, similar to what
+ # is currently done when there are more than one head
+ # (i.e. 'tip')
+ #
+ # replaced changesets: same as divergent except we know there
+ # is no conflict
+ #
+ # pruned changeset: no update is done; though, we could
+ # consider updating to the first non-obsolete parent,
+ # similar to what is current done for 'hg prune'
+
+ if successors:
+ # flatten the list here handles both divergent (len > 1)
+ # and the usual case (len = 1)
+ successors = [n for sub in successors for n in sub]
+
+ # get the max revision for the given successors set,
+ # i.e. the 'tip' of a set
+ node = repo.revs('max(%ln)', successors).first()
+ if bookmarks.isactivewdirparent(repo):
+ movemark = repo['.'].node()
+ return node, movemark, None
+
+def _destupdatebook(repo, clean, check):
+ """decide on an update destination from active bookmark"""
+ # we also move the active bookmark, if any
+ activemark = None
+ node, movemark = bookmarks.calculateupdate(repo.ui, repo, None)
+ if node is not None:
+ activemark = node
+ return node, movemark, activemark
+
+def _destupdatebranch(repo, clean, check):
+ """decide on an update destination from current branch"""
+ wc = repo[None]
+ movemark = node = None
+ try:
+ node = repo.branchtip(wc.branch())
+ if bookmarks.isactivewdirparent(repo):
+ movemark = repo['.'].node()
+ except error.RepoLookupError:
+ if wc.branch() == 'default': # no default branch!
+ node = repo.lookup('tip') # update to tip
+ else:
+ raise error.Abort(_("branch %s not found") % wc.branch())
+ return node, movemark, None
+
+# order in which each step should be evalutated
+# steps are run until one finds a destination
+destupdatesteps = ['evolution', 'bookmark', 'branch']
+# mapping to ease extension overriding steps.
+destupdatestepmap = {'evolution': _destupdateobs,
+ 'bookmark': _destupdatebook,
+ 'branch': _destupdatebranch,
+ }
+
+def destupdate(repo, clean=False, check=False):
+ """destination for bare update operation
+
+ return (rev, movemark, activemark)
+
+ - rev: the revision to update to,
+ - movemark: node to move the active bookmark from
+ (cf bookmark.calculate update),
+ - activemark: a bookmark to activate at the end of the update.
+ """
+ node = movemark = activemark = None
+
+ for step in destupdatesteps:
+ node, movemark, activemark = destupdatestepmap[step](repo, clean, check)
+ if node is not None:
+ break
+ rev = repo[node].rev()
+
+ _destupdatevalidate(repo, rev, clean, check)
+
+ return rev, movemark, activemark
+
+def _destmergebook(repo):
+ """find merge destination in the active bookmark case"""
+ node = None
+ bmheads = repo.bookmarkheads(repo._activebookmark)
+ curhead = repo[repo._activebookmark].node()
+ if len(bmheads) == 2:
+ if curhead == bmheads[0]:
+ node = bmheads[1]
+ else:
+ node = bmheads[0]
+ elif len(bmheads) > 2:
+ raise error.Abort(_("multiple matching bookmarks to merge - "
+ "please merge with an explicit rev or bookmark"),
+ hint=_("run 'hg heads' to see all heads"))
+ elif len(bmheads) <= 1:
+ raise error.Abort(_("no matching bookmark to merge - "
+ "please merge with an explicit rev or bookmark"),
+ hint=_("run 'hg heads' to see all heads"))
+ assert node is not None
+ return node
+
+def _destmergebranch(repo):
+ """find merge destination based on branch heads"""
+ node = None
+ branch = repo[None].branch()
+ bheads = repo.branchheads(branch)
+ nbhs = [bh for bh in bheads if not repo[bh].bookmarks()]
+
+ if len(nbhs) > 2:
+ raise error.Abort(_("branch '%s' has %d heads - "
+ "please merge with an explicit rev")
+ % (branch, len(bheads)),
+ hint=_("run 'hg heads .' to see heads"))
+
+ parent = repo.dirstate.p1()
+ if len(nbhs) <= 1:
+ if len(bheads) > 1:
+ raise error.Abort(_("heads are bookmarked - "
+ "please merge with an explicit rev"),
+ hint=_("run 'hg heads' to see all heads"))
+ if len(repo.heads()) > 1:
+ raise error.Abort(_("branch '%s' has one head - "
+ "please merge with an explicit rev")
+ % branch,
+ hint=_("run 'hg heads' to see all heads"))
+ msg, hint = _('nothing to merge'), None
+ if parent != repo.lookup(branch):
+ hint = _("use 'hg update' instead")
+ raise error.Abort(msg, hint=hint)
+
+ if parent not in bheads:
+ raise error.Abort(_('working directory not at a head revision'),
+ hint=_("use 'hg update' or merge with an "
+ "explicit revision"))
+ if parent == nbhs[0]:
+ node = nbhs[-1]
+ else:
+ node = nbhs[0]
+ assert node is not None
+ return node
+
+def destmerge(repo):
+ if repo._activebookmark:
+ node = _destmergebook(repo)
+ else:
+ node = _destmergebranch(repo)
+ return repo[node].rev()