Merged with Trevor's -rr branch

25 files changed, 2452 insertions, 1464 deletions

diff --git a/interfaces/web/Bugs-Everywhere-Web/beweb/controllers.py b/interfaces/web/Bugs-Everywhere-Web/beweb/controllers.py
index a0d0ff9..50cc754 100644
--- a/interfaces/web/Bugs-Everywhere-Web/beweb/controllers.py
+++ b/interfaces/web/Bugs-Everywhere-Web/beweb/controllers.py
@@ -119,9 +119,9 @@ class Bug(PrestHandler):
             assigned = None
         bug.assigned = assigned
         bug.save()
-#        bug.rcs.precommit(bug.path)
-#        bug.rcs.commit(bug.path, "Auto-commit")
-#        bug.rcs.postcommit(bug.path)
+#        bug.vcs.precommit(bug.path)
+#        bug.vcs.commit(bug.path, "Auto-commit")
+#        bug.vcs.postcommit(bug.path)
         raise cherrypy.HTTPRedirect(bug_list_url(bug_data["project"]))
 
     def instantiate(self, project, bug):
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/arch.py b/interfaces/web/Bugs-Everywhere-Web/libbe/arch.py
index 2f45aa9..ab55172 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/arch.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/arch.py
@@ -17,6 +17,10 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+"""
+GNU Arch (tla) backend.
+"""
+
 import codecs
 import os
 import re
@@ -26,10 +30,11 @@ import time
 import unittest
 import doctest
 
-import config
 from beuuid import uuid_gen
-import rcs
-from rcs import RCS
+import config
+import vcs
+
+
 
 DEFAULT_CLIENT = "tla"
 
@@ -38,7 +43,7 @@ client = config.get_val("arch_client", default=DEFAULT_CLIENT)
 def new():
     return Arch()
 
-class Arch(RCS):
+class Arch(vcs.VCS):
     name = "Arch"
     client = client
     versioned = True
@@ -48,21 +53,25 @@ class Arch(RCS):
     _project_name = None
     _tmp_project = False
     _arch_paramdir = os.path.expanduser("~/.arch-params")
-    def _rcs_help(self):
+    def _vcs_help(self):
         status,output,error = self._u_invoke_client("--help")
         return output
-    def _rcs_detect(self, path):
+    def _vcs_detect(self, path):
         """Detect whether a directory is revision-controlled using Arch"""
         if self._u_search_parent_directories(path, "{arch}") != None :
             config.set_val("arch_client", client)
             return True
         return False
-    def _rcs_init(self, path):
+    def _vcs_init(self, path):
         self._create_archive(path)
         self._create_project(path)
         self._add_project_code(path)
     def _create_archive(self, path):
-        # Create a new archive
+        """
+        Create a temporary Arch archive in the directory PATH.  This
+        archive will be removed by
+          __del__->cleanup->_vcs_cleanup->_remove_archive
+        """
         # http://regexps.srparish.net/tutorial-tla/new-archive.html#Creating_a_New_Archive
         assert self._archive_name == None
         id = self.get_user_id()
@@ -103,7 +112,7 @@ class Arch(RCS):
         """
         Create a temporary Arch project in the directory PATH.  This
         project will be removed by
-          __del__->cleanup->_rcs_cleanup->_remove_project
+          __del__->cleanup->_vcs_cleanup->_remove_project
         """
         # http://mwolson.org/projects/GettingStartedWithArch.html
         # http://regexps.srparish.net/tutorial-tla/new-project.html#Starting_a_New_Project
@@ -159,13 +168,13 @@ class Arch(RCS):
         self._adjust_naming_conventions(path)
         self._invoke_client("import", "--summary", "Began versioning",
                             directory=path)
-    def _rcs_cleanup(self):
+    def _vcs_cleanup(self):
         if self._tmp_project == True:
             self._remove_project()
         if self._tmp_archive == True:
             self._remove_archive()
 
-    def _rcs_root(self, path):
+    def _vcs_root(self, path):
         if not os.path.isdir(path):
             dirname = os.path.dirname(path)
         else:
@@ -176,7 +185,6 @@ class Arch(RCS):
         self._get_archive_project_name(root)
 
         return root
-
     def _get_archive_name(self, root):
         status,output,error = self._u_invoke_client("archives")
         lines = output.split('\n')
@@ -188,7 +196,6 @@ class Arch(RCS):
             if os.path.realpath(location) == os.path.realpath(root):
                 self._archive_name = archive
         assert self._archive_name != None
-
     def _get_archive_project_name(self, root):
         # get project names
         status,output,error = self._u_invoke_client("tree-version", directory=root)
@@ -197,7 +204,7 @@ class Arch(RCS):
         archive_name,project_name = output.rstrip('\n').split('/')
         self._archive_name = archive_name
         self._project_name = project_name
-    def _rcs_get_user_id(self):
+    def _vcs_get_user_id(self):
         try:
             status,output,error = self._u_invoke_client('my-id')
             return output.rstrip('\n')
@@ -206,9 +213,9 @@ class Arch(RCS):
                 return None
             else:
                 raise
-    def _rcs_set_user_id(self, value):
+    def _vcs_set_user_id(self, value):
         self._u_invoke_client('my-id', value)
-    def _rcs_add(self, path):
+    def _vcs_add(self, path):
         self._u_invoke_client("add-id", path)
         realpath = os.path.realpath(self._u_abspath(path))
         pathAdded = realpath in self._list_added(self.rootdir)
@@ -237,14 +244,14 @@ class Arch(RCS):
         self._add_dir_rule(rule, os.path.dirname(path), self.rootdir)
         if os.path.realpath(path) not in self._list_added(self.rootdir):
             raise CantAddFile(path)
-    def _rcs_remove(self, path):
+    def _vcs_remove(self, path):
         if not '.arch-ids' in path:
             self._u_invoke_client("delete-id", path)
-    def _rcs_update(self, path):
+    def _vcs_update(self, path):
         pass
-    def _rcs_get_file_contents(self, path, revision=None, binary=False):
+    def _vcs_get_file_contents(self, path, revision=None, binary=False):
         if revision == None:
-            return RCS._rcs_get_file_contents(self, path, revision, binary=binary)
+            return vcs.VCS._vcs_get_file_contents(self, path, revision, binary=binary)
         else:
             status,output,error = \
                 self._invoke_client("file-find", path, revision)
@@ -254,18 +261,18 @@ class Arch(RCS):
             contents = f.read()
             f.close()
             return contents
-    def _rcs_duplicate_repo(self, directory, revision=None):
+    def _vcs_duplicate_repo(self, directory, revision=None):
         if revision == None:
-            RCS._rcs_duplicate_repo(self, directory, revision)
+            vcs.VCS._vcs_duplicate_repo(self, directory, revision)
         else:
             status,output,error = \
                 self._u_invoke_client("get", revision,directory)
-    def _rcs_commit(self, commitfile, allow_empty=False):
+    def _vcs_commit(self, commitfile, allow_empty=False):
         if allow_empty == False:
             # arch applies empty commits without complaining, so check first
             status,output,error = self._u_invoke_client("changes",expect=(0,1))
             if status == 0:
-                raise rcs.EmptyCommit()
+                raise vcs.EmptyCommit()
         summary,body = self._u_parse_commitfile(commitfile)
         args = ["commit", "--summary", summary]
         if body != None:
@@ -281,6 +288,16 @@ class Arch(RCS):
         assert revpath.startswith(self._archive_project_name()+'--')
         revision = revpath[len(self._archive_project_name()+'--'):]
         return revpath
+    def _vcs_revision_id(self, index):
+        status,output,error = self._u_invoke_client("logs")
+        logs = output.splitlines()
+        first_log = logs.pop(0)
+        assert first_log == "base-0", first_log
+        try:
+            log = logs[index]
+        except IndexError:
+            return None
+        return "%s--%s" % (self._archive_project_name(), log)
 
 class CantAddFile(Exception):
     def __init__(self, file):
@@ -289,7 +306,7 @@ class CantAddFile(Exception):
 
 
 
-rcs.make_rcs_testcase_subclasses(Arch, sys.modules[__name__])
+vcs.make_vcs_testcase_subclasses(Arch, sys.modules[__name__])
 
 unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
 suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/beuuid.py b/interfaces/web/Bugs-Everywhere-Web/libbe/beuuid.py
index bc47208..490ed62 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/beuuid.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/beuuid.py
@@ -13,6 +13,7 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
 """
 Backwards compatibility support for Python 2.4.  Once people give up
 on 2.4 ;), the uuid call should be merged into bugdir.py
@@ -20,6 +21,7 @@ on 2.4 ;), the uuid call should be merged into bugdir.py
 
 import unittest
 
+
 try:
     from uuid import uuid4 # Python >= 2.5
     def uuid_gen():
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/bug.py b/interfaces/web/Bugs-Everywhere-Web/libbe/bug.py
index c1e5481..fd30ff7 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/bug.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/bug.py
@@ -15,6 +15,11 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Define the Bug class for representing bugs.
+"""
+
 import os
 import os.path
 import errno
@@ -33,6 +38,11 @@ import comment
 import utility
 
 
+class DiskAccessRequired (Exception):
+    def __init__(self, goal):
+        msg = "Cannot %s without accessing the disk" % goal
+        Exception.__init__(self, msg)
+
 ### Define and describe valid bug categories
 # Use a tuple of (category, description) tuples since we don't have
 # ordered dicts in Python yet http://www.python.org/dev/peps/pep-0372/
@@ -216,15 +226,15 @@ class Bug(settings_object.SavedSettingsObject):
     @doc_property(doc="The trunk of the comment tree")
     def comment_root(): return {}
 
-    def _get_rcs(self):
-        if hasattr(self.bugdir, "rcs"):
-            return self.bugdir.rcs
+    def _get_vcs(self):
+        if hasattr(self.bugdir, "vcs"):
+            return self.bugdir.vcs
 
     @Property
-    @cached_property(generator=_get_rcs)
-    @local_property("rcs")
+    @cached_property(generator=_get_vcs)
+    @local_property("vcs")
     @doc_property(doc="A revision control system instance.")
-    def rcs(): return {}
+    def vcs(): return {}
 
     def __init__(self, bugdir=None, uuid=None, from_disk=False,
                  load_comments=False, summary=None):
@@ -238,17 +248,20 @@ class Bug(settings_object.SavedSettingsObject):
             if uuid == None:
                 self.uuid = uuid_gen()
             self.time = int(time.time()) # only save to second precision
-            if self.rcs != None:
-                self.creator = self.rcs.get_user_id()
+            if self.vcs != None:
+                self.creator = self.vcs.get_user_id()
             self.summary = summary
 
     def __repr__(self):
         return "Bug(uuid=%r)" % self.uuid
 
-    def set_sync_with_disk(self, value):
-        self.sync_with_disk = value
-        for comment in self.comments():
-            comment.set_sync_with_disk(value)
+    def __str__(self):
+        return self.string(shortlist=True)
+
+    def __cmp__(self, other):
+        return cmp_full(self, other)
+
+    # serializing methods
 
     def _setting_attr_string(self, setting):
         value = getattr(self, setting)
@@ -331,43 +344,34 @@ class Bug(settings_object.SavedSettingsObject):
             output = bugout
         return output
 
-    def __str__(self):
-        return self.string(shortlist=True)
+    # methods for saving/loading/acessing settings and properties.
 
-    def __cmp__(self, other):
-        return cmp_full(self, other)
+    def get_path(self, *args):
+        dir = os.path.join(self.bugdir.get_path("bugs"), self.uuid)
+        if len(args) == 0:
+            return dir
+        assert args[0] in ["values", "comments"], str(args)
+        return os.path.join(dir, *args)
 
-    def get_path(self, name=None):
-        my_dir = os.path.join(self.bugdir.get_path("bugs"), self.uuid)
-        if name is None:
-            return my_dir
-        assert name in ["values", "comments"]
-        return os.path.join(my_dir, name)
+    def set_sync_with_disk(self, value):
+        self.sync_with_disk = value
+        for comment in self.comments():
+            comment.set_sync_with_disk(value)
 
     def load_settings(self):
-        self.settings = mapfile.map_load(self.rcs, self.get_path("values"))
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("load settings")
+        self.settings = mapfile.map_load(self.vcs, self.get_path("values"))
         self._setup_saved_settings()
 
-    def load_comments(self, load_full=True):
-        if load_full == True:
-            # Force a complete load of the whole comment tree
-            self.comment_root = self._get_comment_root(load_full=True)
-        else:
-            # Setup for fresh lazy-loading.  Clear _comment_root, so
-            # _get_comment_root returns a fresh version.  Turn of
-            # syncing temporarily so we don't write our blank comment
-            # tree to disk.
-            self.sync_with_disk = False
-            self.comment_root = None
-            self.sync_with_disk = True
-
     def save_settings(self):
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("save settings")
         assert self.summary != None, "Can't save blank bug"
-        
-        self.rcs.mkdir(self.get_path())
+        self.vcs.mkdir(self.get_path())
         path = self.get_path("values")
-        mapfile.map_save(self.rcs, path, self._get_saved_settings())
-        
+        mapfile.map_save(self.vcs, path, self._get_saved_settings())
+
     def save(self):
         """
         Save any loaded contents to disk.  Because of lazy loading of
@@ -378,15 +382,39 @@ class Bug(settings_object.SavedSettingsObject):
         calling this method will just waste time (unless something
         else has been messing with your on-disk files).
         """
+        sync_with_disk = self.sync_with_disk
+        if sync_with_disk == False:
+            self.set_sync_with_disk(True)
         self.save_settings()
         if len(self.comment_root) > 0:
             comment.saveComments(self)
+        if sync_with_disk == False:
+            self.set_sync_with_disk(False)
+
+    def load_comments(self, load_full=True):
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("load comments")
+        if load_full == True:
+            # Force a complete load of the whole comment tree
+            self.comment_root = self._get_comment_root(load_full=True)
+        else:
+            # Setup for fresh lazy-loading.  Clear _comment_root, so
+            # _get_comment_root returns a fresh version.  Turn of
+            # syncing temporarily so we don't write our blank comment
+            # tree to disk.
+            self.sync_with_disk = False
+            self.comment_root = None
+            self.sync_with_disk = True
 
     def remove(self):
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("remove")
         self.comment_root.remove()
         path = self.get_path()
-        self.rcs.recursive_remove(path)
+        self.vcs.recursive_remove(path)
     
+    # methods for managing comments
+
     def comments(self):
         for comment in self.comment_root.traverse():
             yield comment
@@ -489,8 +517,12 @@ def cmp_attr(bug_1, bug_2, attr, invert=False):
         return cmp(val_1, val_2)
 
 # alphabetical rankings (a < z)
+cmp_uuid = lambda bug_1, bug_2 : cmp_attr(bug_1, bug_2, "uuid")
 cmp_creator = lambda bug_1, bug_2 : cmp_attr(bug_1, bug_2, "creator")
 cmp_assigned = lambda bug_1, bug_2 : cmp_attr(bug_1, bug_2, "assigned")
+cmp_target = lambda bug_1, bug_2 : cmp_attr(bug_1, bug_2, "target")
+cmp_reporter = lambda bug_1, bug_2 : cmp_attr(bug_1, bug_2, "reporter")
+cmp_summary = lambda bug_1, bug_2 : cmp_attr(bug_1, bug_2, "summary")
 # chronological rankings (newer < older)
 cmp_time = lambda bug_1, bug_2 : cmp_attr(bug_1, bug_2, "time", invert=True)
 
@@ -512,7 +544,8 @@ def cmp_comments(bug_1, bug_2):
     return 0
 
 DEFAULT_CMP_FULL_CMP_LIST = \
-    (cmp_status,cmp_severity,cmp_assigned,cmp_time,cmp_creator,cmp_comments)
+    (cmp_status, cmp_severity, cmp_assigned, cmp_time, cmp_creator,
+     cmp_reporter, cmp_target, cmp_comments, cmp_summary, cmp_uuid)
 
 class BugCompoundComparator (object):
     def __init__(self, cmp_list=DEFAULT_CMP_FULL_CMP_LIST):
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/bugdir.py b/interfaces/web/Bugs-Everywhere-Web/libbe/bugdir.py
index 6e020ee..c4f0f91 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/bugdir.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/bugdir.py
@@ -17,23 +17,30 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Define the BugDir class for representing bug comments.
+"""
+
+import copy
+import errno
 import os
 import os.path
-import errno
+import sys
 import time
-import copy
 import unittest
 import doctest
 
+import bug
+import encoding
 from properties import Property, doc_property, local_property, \
     defaulting_property, checked_property, fn_checked_property, \
     cached_property, primed_property, change_hook_property, \
     settings_property
-import settings_object
 import mapfile
-import bug
-import rcs
-import encoding
+import vcs
+import settings_object
+import upgrade
 import utility
 
 
@@ -62,8 +69,16 @@ class MultipleBugMatches(ValueError):
         self.shortname = shortname
         self.matches = matches
 
+class NoBugMatches(KeyError):
+    def __init__(self, shortname):
+        msg = "No bug matches %s" % shortname
+        KeyError.__init__(self, msg)
+        self.shortname = shortname
 
-TREE_VERSION_STRING = "Bugs Everywhere Tree 1 0\n"
+class DiskAccessRequired (Exception):
+    def __init__(self, goal):
+        msg = "Cannot %s without accessing the disk" % goal
+        Exception.__init__(self, msg)
 
 
 class BugDir (list, settings_object.SavedSettingsObject):
@@ -99,7 +114,8 @@ class BugDir (list, settings_object.SavedSettingsObject):
     all bugs/comments/etc. that have been loaded into memory.  If
     you've been living in memory and want to move to
     .sync_with_disk==True, but you're not sure if anything has been
-    changed in memoryy, a call to save() is a safe move.
+    changed in memory, a call to save() immediately before the
+    .set_sync_with_disk(True) call is a safe move.
 
     Regardless of .sync_with_disk, a call to .save() will write out
     all the contents that the BugDir instance has loaded into memory.
@@ -107,15 +123,14 @@ class BugDir (list, settings_object.SavedSettingsObject):
     changes, this .save() call will be a waste of time.
 
     The BugDir will only load information from the file system when it
-    loads new bugs/comments that it doesn't already have in memory, or
-    when it explicitly asked to do so (e.g. .load() or
-    __init__(from_disk=True)).
+    loads new settings/bugs/comments that it doesn't already have in
+    memory and .sync_with_disk == True.
 
-    Allow RCS initialization
+    Allow VCS initialization
     ========================
 
     This one is for testing purposes.  Setting it to True allows the
-    BugDir to search for an installed RCS backend and initialize it in
+    BugDir to search for an installed VCS backend and initialize it in
     the root directory.  This is a convenience option for supporting
     tests of versioning functionality (e.g. .duplicate_bugdir).
 
@@ -172,9 +187,9 @@ class BugDir (list, settings_object.SavedSettingsObject):
     def encoding(): return {}
 
     def _setup_user_id(self, user_id):
-        self.rcs.user_id = user_id
+        self.vcs.user_id = user_id
     def _guess_user_id(self):
-        return self.rcs.get_user_id()
+        return self.vcs.get_user_id()
     def _set_user_id(self, old_user_id, new_user_id):
         self._setup_user_id(new_user_id)
         self._prop_save_settings(old_user_id, new_user_id)
@@ -182,7 +197,7 @@ class BugDir (list, settings_object.SavedSettingsObject):
     @_versioned_property(name="user_id",
                          doc=
 """The user's prefered name, e.g. 'John Doe <jdoe@example.com>'.  Note
-that the Arch RCS backend *enforces* ids with this format.""",
+that the Arch VCS backend *enforces* ids with this format.""",
                          change_hook=_set_user_id,
                          generator=_guess_user_id)
     def user_id(): return {}
@@ -192,32 +207,32 @@ that the Arch RCS backend *enforces* ids with this format.""",
 """The default assignee for new bugs e.g. 'John Doe <jdoe@example.com>'.""")
     def default_assignee(): return {}
 
-    @_versioned_property(name="rcs_name",
-                         doc="""The name of the current RCS.  Kept seperate to make saving/loading
-settings easy.  Don't set this attribute.  Set .rcs instead, and
-.rcs_name will be automatically adjusted.""",
+    @_versioned_property(name="vcs_name",
+                         doc="""The name of the current VCS.  Kept seperate to make saving/loading
+settings easy.  Don't set this attribute.  Set .vcs instead, and
+.vcs_name will be automatically adjusted.""",
                          default="None",
                          allowed=["None", "Arch", "bzr", "darcs", "git", "hg"])
-    def rcs_name(): return {}
+    def vcs_name(): return {}
 
-    def _get_rcs(self, rcs_name=None):
+    def _get_vcs(self, vcs_name=None):
         """Get and root a new revision control system"""
-        if rcs_name == None:
-            rcs_name = self.rcs_name
-        new_rcs = rcs.rcs_by_name(rcs_name)
-        self._change_rcs(None, new_rcs)
-        return new_rcs
-    def _change_rcs(self, old_rcs, new_rcs):
-        new_rcs.encoding = self.encoding
-        new_rcs.root(self.root)
-        self.rcs_name = new_rcs.name
+        if vcs_name == None:
+            vcs_name = self.vcs_name
+        new_vcs = vcs.vcs_by_name(vcs_name)
+        self._change_vcs(None, new_vcs)
+        return new_vcs
+    def _change_vcs(self, old_vcs, new_vcs):
+        new_vcs.encoding = self.encoding
+        new_vcs.root(self.root)
+        self.vcs_name = new_vcs.name
 
     @Property
-    @change_hook_property(hook=_change_rcs)
-    @cached_property(generator=_get_rcs)
-    @local_property("rcs")
+    @change_hook_property(hook=_change_vcs)
+    @cached_property(generator=_get_vcs)
+    @local_property("vcs")
     @doc_property(doc="A revision control system instance.")
-    def rcs(): return {}
+    def vcs(): return {}
 
     def _bug_map_gen(self):
         map = {}
@@ -279,9 +294,8 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
 
 
     def __init__(self, root=None, sink_to_existing_root=True,
-                 assert_new_BugDir=False, allow_rcs_init=False,
-                 manipulate_encodings=True,
-                 from_disk=False, rcs=None):
+                 assert_new_BugDir=False, allow_vcs_init=False,
+                 manipulate_encodings=True, from_disk=False, vcs=None):
         list.__init__(self)
         settings_object.SavedSettingsObject.__init__(self)
         self._manipulate_encodings = manipulate_encodings
@@ -293,9 +307,9 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
             if not os.path.exists(root):
                 raise NoRootEntry(root)
             self.root = root
-        # get a temporary rcs until we've loaded settings
+        # get a temporary vcs until we've loaded settings
         self.sync_with_disk = False
-        self.rcs = self._guess_rcs()
+        self.vcs = self._guess_vcs()
 
         if from_disk == True:
             self.sync_with_disk = True
@@ -305,20 +319,24 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
             if assert_new_BugDir == True:
                 if os.path.exists(self.get_path()):
                     raise AlreadyInitialized, self.get_path()
-            if rcs == None:
-                rcs = self._guess_rcs(allow_rcs_init)
-            self.rcs = rcs
+            if vcs == None:
+                vcs = self._guess_vcs(allow_vcs_init)
+            self.vcs = vcs
             self._setup_user_id(self.user_id)
 
-    def set_sync_with_disk(self, value):
-        self.sync_with_disk = value
-        for bug in self:
-            bug.set_sync_with_disk(value)
+    def __del__(self):
+        self.cleanup()
+
+    def cleanup(self):
+        self.vcs.cleanup()
+
+    # methods for getting the BugDir situated in the filesystem
 
     def _find_root(self, path):
         """
         Search for an existing bug database dir and it's ancestors and
-        return a BugDir rooted there.
+        return a BugDir rooted there.  Only called by __init__, and
+        then only if sink_to_existing_root == True.
         """
         if not os.path.exists(path):
             raise NoRootEntry(path)
@@ -334,136 +352,212 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
                 raise NoBugDir(path)
             return beroot
 
-    def get_version(self, path=None, use_none_rcs=False):
-        if use_none_rcs == True:
-            RCS = rcs.rcs_by_name("None")
-            RCS.root(self.root)
-            RCS.encoding = encoding.get_encoding()
+    def _guess_vcs(self, allow_vcs_init=False):
+        """
+        Only called by __init__.
+        """
+        deepdir = self.get_path()
+        if not os.path.exists(deepdir):
+            deepdir = os.path.dirname(deepdir)
+        new_vcs = vcs.detect_vcs(deepdir)
+        install = False
+        if new_vcs.name == "None":
+            if allow_vcs_init == True:
+                new_vcs = vcs.installed_vcs()
+                new_vcs.init(self.root)
+        return new_vcs
+
+    # methods for saving/loading/accessing settings and properties.
+
+    def get_path(self, *args):
+        """
+        Return a path relative to .root.
+        """
+        dir = os.path.join(self.root, ".be")
+        if len(args) == 0:
+            return dir
+        assert args[0] in ["version", "settings", "bugs"], str(args)
+        return os.path.join(dir, *args)
+
+    def _get_settings(self, settings_path, for_duplicate_bugdir=False):
+        allow_no_vcs = not self.vcs.path_in_root(settings_path)
+        if allow_no_vcs == True:
+            assert for_duplicate_bugdir == True
+        if self.sync_with_disk == False and for_duplicate_bugdir == False:
+            # duplicates can ignore this bugdir's .sync_with_disk status
+            raise DiskAccessRequired("_get settings")
+        try:
+            settings = mapfile.map_load(self.vcs, settings_path, allow_no_vcs)
+        except vcs.NoSuchFile:
+            settings = {"vcs_name": "None"}
+        return settings
+
+    def _save_settings(self, settings_path, settings,
+                       for_duplicate_bugdir=False):
+        allow_no_vcs = not self.vcs.path_in_root(settings_path)
+        if allow_no_vcs == True:
+            assert for_duplicate_bugdir == True
+        if self.sync_with_disk == False and for_duplicate_bugdir == False:
+            # duplicates can ignore this bugdir's .sync_with_disk status
+            raise DiskAccessRequired("_save settings")
+        self.vcs.mkdir(self.get_path(), allow_no_vcs)
+        mapfile.map_save(self.vcs, settings_path, settings, allow_no_vcs)
+
+    def load_settings(self):
+        self.settings = self._get_settings(self.get_path("settings"))
+        self._setup_saved_settings()
+        self._setup_user_id(self.user_id)
+        self._setup_encoding(self.encoding)
+        self._setup_severities(self.severities)
+        self._setup_status(self.active_status, self.inactive_status)
+        self.vcs = vcs.vcs_by_name(self.vcs_name)
+        self._setup_user_id(self.user_id)
+
+    def save_settings(self):
+        settings = self._get_saved_settings()
+        self._save_settings(self.get_path("settings"), settings)
+
+    def get_version(self, path=None, use_none_vcs=False,
+                    for_duplicate_bugdir=False):
+        """
+        Requires disk access.
+        """
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("get version")
+        if use_none_vcs == True:
+            VCS = vcs.vcs_by_name("None")
+            VCS.root(self.root)
+            VCS.encoding = encoding.get_encoding()
         else:
-            RCS = self.rcs
+            VCS = self.vcs
 
         if path == None:
             path = self.get_path("version")
-        tree_version = RCS.get_file_contents(path)
-        return tree_version
+        allow_no_vcs = not VCS.path_in_root(path)
+        if allow_no_vcs == True:
+            assert for_duplicate_bugdir == True
+        version = VCS.get_file_contents(
+            path, allow_no_vcs=allow_no_vcs).rstrip("\n")
+        return version
 
     def set_version(self):
-        self.rcs.mkdir(self.get_path())
-        self.rcs.set_file_contents(self.get_path("version"),
-                                   TREE_VERSION_STRING)
+        """
+        Requires disk access.
+        """
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("set version")
+        self.vcs.mkdir(self.get_path())
+        self.vcs.set_file_contents(self.get_path("version"),
+                                   upgrade.BUGDIR_DISK_VERSION+"\n")
 
-    def get_path(self, *args):
-        my_dir = os.path.join(self.root, ".be")
-        if len(args) == 0:
-            return my_dir
-        assert args[0] in ["version", "settings", "bugs"], str(args)
-        return os.path.join(my_dir, *args)
+    # methods controlling disk access
 
-    def _guess_rcs(self, allow_rcs_init=False):
-        deepdir = self.get_path()
-        if not os.path.exists(deepdir):
-            deepdir = os.path.dirname(deepdir)
-        new_rcs = rcs.detect_rcs(deepdir)
-        install = False
-        if new_rcs.name == "None":
-            if allow_rcs_init == True:
-                new_rcs = rcs.installed_rcs()
-                new_rcs.init(self.root)
-        return new_rcs
+    def set_sync_with_disk(self, value):
+        """
+        Adjust .sync_with_disk for the BugDir and all it's children.
+        See the BugDir docstring for a description of the role of
+        .sync_with_disk.
+        """
+        self.sync_with_disk = value
+        for bug in self:
+            bug.set_sync_with_disk(value)
 
     def load(self):
-        version = self.get_version(use_none_rcs=True)
-        if version != TREE_VERSION_STRING:
-            raise NotImplementedError, \
-                "BugDir cannot handle version '%s' yet." % version
+        """
+        Reqires disk access
+        """
+        version = self.get_version(use_none_vcs=True)
+        if version != upgrade.BUGDIR_DISK_VERSION:
+            upgrade.upgrade(self.root, version)
         else:
             if not os.path.exists(self.get_path()):
                 raise NoBugDir(self.get_path())
             self.load_settings()
 
-            self.rcs = rcs.rcs_by_name(self.rcs_name)
-            self._setup_user_id(self.user_id)
-
     def load_all_bugs(self):
-        "Warning: this could take a while."
+        """
+        Requires disk access.
+        Warning: this could take a while.
+        """
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("load all bugs")
         self._clear_bugs()
         for uuid in self.list_uuids():
             self._load_bug(uuid)
 
     def save(self):
         """
+        Note that this command writes to disk _regardless_ of the
+        status of .sync_with_disk.
+
         Save any loaded contents to disk.  Because of lazy loading of
         bugs and comments, this is actually not too inefficient.
 
-        However, if self.sync_with_disk = True, then any changes are
+        However, if .sync_with_disk = True, then any changes are
         automatically written to disk as soon as they happen, so
         calling this method will just waste time (unless something
         else has been messing with your on-disk files).
+
+        Requires disk access.
         """
+        sync_with_disk = self.sync_with_disk
+        if sync_with_disk == False:
+            self.set_sync_with_disk(True)
         self.set_version()
         self.save_settings()
         for bug in self:
             bug.save()
+        if sync_with_disk == False:
+            self.set_sync_with_disk(sync_with_disk)
 
-    def load_settings(self):
-        self.settings = self._get_settings(self.get_path("settings"))
-        self._setup_saved_settings()
-        self._setup_user_id(self.user_id)
-        self._setup_encoding(self.encoding)
-        self._setup_severities(self.severities)
-        self._setup_status(self.active_status, self.inactive_status)
+    # methods for managing duplicate BugDirs
 
-    def _get_settings(self, settings_path):
-        allow_no_rcs = not self.rcs.path_in_root(settings_path)
-        # allow_no_rcs=True should only be for the special case of
-        # configuring duplicate bugdir settings
+    def duplicate_bugdir(self, revision):
+        duplicate_path = self.vcs.duplicate_repo(revision)
 
+        duplicate_version_path = os.path.join(duplicate_path, ".be", "version")
         try:
-            settings = mapfile.map_load(self.rcs, settings_path, allow_no_rcs)
-        except rcs.NoSuchFile:
-            settings = {"rcs_name": "None"}
-        return settings
-
-    def save_settings(self):
-        settings = self._get_saved_settings()
-        self._save_settings(self.get_path("settings"), settings)
-
-    def _save_settings(self, settings_path, settings):
-        allow_no_rcs = not self.rcs.path_in_root(settings_path)
-        # allow_no_rcs=True should only be for the special case of
-        # configuring duplicate bugdir settings
-        self.rcs.mkdir(self.get_path(), allow_no_rcs)
-        mapfile.map_save(self.rcs, settings_path, settings, allow_no_rcs)
-
-    def duplicate_bugdir(self, revision):
-        duplicate_path = self.rcs.duplicate_repo(revision)
+            version = self.get_version(duplicate_version_path,
+                                       for_duplicate_bugdir=True)
+        except DiskAccessRequired:
+            self.sync_with_disk = True # temporarily allow access
+            version = self.get_version(duplicate_version_path,
+                                       for_duplicate_bugdir=True)
+            self.sync_with_disk = False
+        if version != upgrade.BUGDIR_DISK_VERSION:
+            upgrade.upgrade(duplicate_path, version)
 
-        # setup revision RCS as None, since the duplicate may not be
+        # setup revision VCS as None, since the duplicate may not be
         # initialized for versioning
         duplicate_settings_path = os.path.join(duplicate_path,
                                                ".be", "settings")
-        duplicate_settings = self._get_settings(duplicate_settings_path)
-        if "rcs_name" in duplicate_settings:
-            duplicate_settings["rcs_name"] = "None"
+        duplicate_settings = self._get_settings(duplicate_settings_path,
+                                                for_duplicate_bugdir=True)
+        if "vcs_name" in duplicate_settings:
+            duplicate_settings["vcs_name"] = "None"
             duplicate_settings["user_id"] = self.user_id
         if "disabled" in bug.status_values:
             # Hack to support old versions of BE bugs
             duplicate_settings["inactive_status"] = self.inactive_status
-        self._save_settings(duplicate_settings_path, duplicate_settings)
+        self._save_settings(duplicate_settings_path, duplicate_settings,
+                            for_duplicate_bugdir=True)
 
         return BugDir(duplicate_path, from_disk=True, manipulate_encodings=self._manipulate_encodings)
 
     def remove_duplicate_bugdir(self):
-        self.rcs.remove_duplicate_repo()
+        self.vcs.remove_duplicate_repo()
+
+    # methods for managing bugs
 
     def list_uuids(self):
         uuids = []
-        if os.path.exists(self.get_path()):
+        if self.sync_with_disk == True and os.path.exists(self.get_path()):
             # list the uuids on disk
-            for uuid in os.listdir(self.get_path("bugs")):
-                if not (uuid.startswith('.')):
-                    uuids.append(uuid)
-                    yield uuid
+            if os.path.exists(self.get_path("bugs")):
+                for uuid in os.listdir(self.get_path("bugs")):
+                    if not (uuid.startswith('.')):
+                        uuids.append(uuid)
+                        yield uuid
         # and the ones that are still just in memory
         for bug in self:
             if bug.uuid not in uuids:
@@ -476,6 +570,8 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
         self._bug_map_gen()
 
     def _load_bug(self, uuid):
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("_load bug")
         bg = bug.Bug(bugdir=self, uuid=uuid, from_disk=True)
         self.append(bg)
         self._bug_map_gen()
@@ -492,7 +588,8 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
 
     def remove_bug(self, bug):
         self.remove(bug)
-        bug.remove()
+        if bug.sync_with_disk == True:
+            bug.remove()
 
     def bug_shortname(self, bug):
         """
@@ -514,12 +611,13 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
 
     def bug_from_shortname(self, shortname):
         """
-        >>> bd = simple_bug_dir()
+        >>> bd = SimpleBugDir(sync_with_disk=False)
         >>> bug_a = bd.bug_from_shortname('a')
         >>> print type(bug_a)
         <class 'libbe.bug.Bug'>
         >>> print bug_a
         a:om: Bug A
+        >>> bd.cleanup()
         """
         matches = []
         self._bug_map_gen()
@@ -530,7 +628,7 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
             raise MultipleBugMatches(shortname, matches)
         if len(matches) == 1:
             return self.bug_from_uuid(matches[0])
-        raise KeyError("No bug matches %s" % shortname)
+        raise NoBugMatches(shortname)
 
     def bug_from_uuid(self, uuid):
         if not self.has_bug(uuid):
@@ -548,41 +646,56 @@ settings easy.  Don't set this attribute.  Set .rcs instead, and
         return True
 
 
-def simple_bug_dir():
+class SimpleBugDir (BugDir):
     """
-    For testing
-    >>> bugdir = simple_bug_dir()
-    >>> ls = list(bugdir.list_uuids())
-    >>> ls.sort()
-    >>> print ls
+    For testing.  Set sync_with_disk==False for a memory-only bugdir.
+    >>> bugdir = SimpleBugDir()
+    >>> uuids = list(bugdir.list_uuids())
+    >>> uuids.sort()
+    >>> print uuids
     ['a', 'b']
+    >>> bugdir.cleanup()
     """
-    dir = utility.Dir()
-    assert os.path.exists(dir.path)
-    bugdir = BugDir(dir.path, sink_to_existing_root=False, allow_rcs_init=True,
+    def __init__(self, sync_with_disk=True):
+        if sync_with_disk == True:
+            dir = utility.Dir()
+            assert os.path.exists(dir.path)
+            root = dir.path
+            assert_new_BugDir = True
+            vcs_init = True
+        else:
+            root = "/"
+            assert_new_BugDir = False
+            vcs_init = False
+        BugDir.__init__(self, root, sink_to_existing_root=False,
+                    assert_new_BugDir=assert_new_BugDir,
+                    allow_vcs_init=vcs_init,
                     manipulate_encodings=False)
-    bugdir._dir_ref = dir # postpone cleanup since dir.__del__() removes dir.
-    bug_a = bugdir.new_bug("a", summary="Bug A")
-    bug_a.creator = "John Doe <jdoe@example.com>"
-    bug_a.time = 0
-    bug_b = bugdir.new_bug("b", summary="Bug B")
-    bug_b.creator = "Jane Doe <jdoe@example.com>"
-    bug_b.time = 0
-    bug_b.status = "closed"
-    bugdir.save()
-    return bugdir
-
+        if sync_with_disk == True: # postpone cleanup since dir.__del__() removes dir.
+            self._dir_ref = dir
+        bug_a = self.new_bug("a", summary="Bug A")
+        bug_a.creator = "John Doe <jdoe@example.com>"
+        bug_a.time = 0
+        bug_b = self.new_bug("b", summary="Bug B")
+        bug_b.creator = "Jane Doe <jdoe@example.com>"
+        bug_b.time = 0
+        bug_b.status = "closed"
+        if sync_with_disk == True:
+            self.save()
+            self.set_sync_with_disk(True)
+    def cleanup(self):
+        if hasattr(self, "_dir_ref"):
+            self._dir_ref.cleanup()
+        BugDir.cleanup(self)
 
 class BugDirTestCase(unittest.TestCase):
-    def __init__(self, *args, **kwargs):
-        unittest.TestCase.__init__(self, *args, **kwargs)
     def setUp(self):
         self.dir = utility.Dir()
         self.bugdir = BugDir(self.dir.path, sink_to_existing_root=False,
-                             allow_rcs_init=True)
-        self.rcs = self.bugdir.rcs
+                             allow_vcs_init=True)
+        self.vcs = self.bugdir.vcs
     def tearDown(self):
-        self.rcs.cleanup()
+        self.bugdir.cleanup()
         self.dir.cleanup()
     def fullPath(self, path):
         return os.path.join(self.dir.path, path)
@@ -593,13 +706,13 @@ class BugDirTestCase(unittest.TestCase):
         self.assertRaises(AlreadyInitialized, BugDir,
                           self.dir.path, assertNewBugDir=True)
     def versionTest(self):
-        if self.rcs.versioned == False:
+        if self.vcs.versioned == False:
             return
-        original = self.bugdir.rcs.commit("Began versioning")
+        original = self.bugdir.vcs.commit("Began versioning")
         bugA = self.bugdir.bug_from_uuid("a")
         bugA.status = "fixed"
         self.bugdir.save()
-        new = self.rcs.commit("Fixed bug a")
+        new = self.vcs.commit("Fixed bug a")
         dupdir = self.bugdir.duplicate_bugdir(original)
         self.failUnless(dupdir.root != self.bugdir.root,
                         "%s, %s" % (dupdir.root, self.bugdir.root))
@@ -645,17 +758,19 @@ class BugDirTestCase(unittest.TestCase):
         rep.new_reply("And they have six legs.")
         if sync_with_disk == False:
             self.bugdir.save()
+            self.bugdir.set_sync_with_disk(True)
         self.bugdir._clear_bugs()
         bug = self.bugdir.bug_from_uuid("a")
         bug.load_comments()
+        if sync_with_disk == False:
+            self.bugdir.set_sync_with_disk(False)
         self.failUnless(len(bug.comment_root)==1, len(bug.comment_root))
         for index,comment in enumerate(bug.comments()):
             if index == 0:
                 repLoaded = comment
                 self.failUnless(repLoaded.uuid == rep.uuid, repLoaded.uuid)
-                self.failUnless(comment.sync_with_disk == True,
+                self.failUnless(comment.sync_with_disk == sync_with_disk,
                                 comment.sync_with_disk)
-                #load_settings()
                 self.failUnless(comment.content_type == "text/plain",
                                 comment.content_type)
                 self.failUnless(repLoaded.settings["Content-type"]=="text/plain",
@@ -672,5 +787,46 @@ class BugDirTestCase(unittest.TestCase):
     def testSyncedComments(self):
         self.testComments(sync_with_disk=True)
 
-unitsuite = unittest.TestLoader().loadTestsFromTestCase(BugDirTestCase)
-suite = unittest.TestSuite([unitsuite])#, doctest.DocTestSuite()])
+class SimpleBugDirTestCase (unittest.TestCase):
+    def setUp(self):
+        # create a pre-existing bugdir in a temporary directory
+        self.dir = utility.Dir()
+        self.original_working_dir = os.getcwd()
+        os.chdir(self.dir.path)
+        self.bugdir = BugDir(self.dir.path, sink_to_existing_root=False,
+                             allow_vcs_init=True)
+        self.bugdir.new_bug("preexisting", summary="Hopefully not imported")
+        self.bugdir.save()
+    def tearDown(self):
+        os.chdir(self.original_working_dir)
+        self.bugdir.cleanup()
+        self.dir.cleanup()
+    def testOnDiskCleanLoad(self):
+        """SimpleBugDir(sync_with_disk==True) should not import preexisting bugs."""
+        bugdir = SimpleBugDir(sync_with_disk=True)
+        self.failUnless(bugdir.sync_with_disk==True, bugdir.sync_with_disk)
+        uuids = sorted([bug.uuid for bug in bugdir])
+        self.failUnless(uuids == ['a', 'b'], uuids)
+        bugdir._clear_bugs()
+        uuids = sorted([bug.uuid for bug in bugdir])
+        self.failUnless(uuids == [], uuids)
+        bugdir.load_all_bugs()
+        uuids = sorted([bug.uuid for bug in bugdir])
+        self.failUnless(uuids == ['a', 'b'], uuids)
+        bugdir.cleanup()
+    def testInMemoryCleanLoad(self):
+        """SimpleBugDir(sync_with_disk==False) should not import preexisting bugs."""
+        bugdir = SimpleBugDir(sync_with_disk=False)
+        self.failUnless(bugdir.sync_with_disk==False, bugdir.sync_with_disk)
+        uuids = sorted([bug.uuid for bug in bugdir])
+        self.failUnless(uuids == ['a', 'b'], uuids)
+        self.failUnlessRaises(DiskAccessRequired, bugdir.load_all_bugs)
+        uuids = sorted([bug.uuid for bug in bugdir])
+        self.failUnless(uuids == ['a', 'b'], uuids)
+        bugdir._clear_bugs()
+        uuids = sorted([bug.uuid for bug in bugdir])
+        self.failUnless(uuids == [], uuids)
+        bugdir.cleanup()
+
+unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
+suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/bzr.py b/interfaces/web/Bugs-Everywhere-Web/libbe/bzr.py
index d7cd1e5..e9e0649 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/bzr.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/bzr.py
@@ -17,61 +17,65 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+"""
+Bazaar (bzr) backend.
+"""
+
 import os
 import re
 import sys
 import unittest
 import doctest
 
-import rcs
-from rcs import RCS
+import vcs
+
 
 def new():
     return Bzr()
 
-class Bzr(RCS):
+class Bzr(vcs.VCS):
     name = "bzr"
     client = "bzr"
     versioned = True
-    def _rcs_help(self):
+    def _vcs_help(self):
         status,output,error = self._u_invoke_client("--help")
         return output        
-    def _rcs_detect(self, path):
+    def _vcs_detect(self, path):
         if self._u_search_parent_directories(path, ".bzr") != None :
             return True
         return False
-    def _rcs_root(self, path):
+    def _vcs_root(self, path):
         """Find the root of the deepest repository containing path."""
         status,output,error = self._u_invoke_client("root", path)
         return output.rstrip('\n')
-    def _rcs_init(self, path):
+    def _vcs_init(self, path):
         self._u_invoke_client("init", directory=path)
-    def _rcs_get_user_id(self):
+    def _vcs_get_user_id(self):
         status,output,error = self._u_invoke_client("whoami")
         return output.rstrip('\n')
-    def _rcs_set_user_id(self, value):
+    def _vcs_set_user_id(self, value):
         self._u_invoke_client("whoami", value)
-    def _rcs_add(self, path):
+    def _vcs_add(self, path):
         self._u_invoke_client("add", path)
-    def _rcs_remove(self, path):
+    def _vcs_remove(self, path):
         # --force to also remove unversioned files.
         self._u_invoke_client("remove", "--force", path)
-    def _rcs_update(self, path):
+    def _vcs_update(self, path):
         pass
-    def _rcs_get_file_contents(self, path, revision=None, binary=False):
+    def _vcs_get_file_contents(self, path, revision=None, binary=False):
         if revision == None:
-            return RCS._rcs_get_file_contents(self, path, revision, binary=binary)
+            return vcs.VCS._vcs_get_file_contents(self, path, revision, binary=binary)
         else:
             status,output,error = \
                 self._u_invoke_client("cat","-r",revision,path)
             return output
-    def _rcs_duplicate_repo(self, directory, revision=None):
+    def _vcs_duplicate_repo(self, directory, revision=None):
         if revision == None:
-            RCS._rcs_duplicate_repo(self, directory, revision)
+            vcs.VCS._vcs_duplicate_repo(self, directory, revision)
         else:
             self._u_invoke_client("branch", "--revision", revision,
                                   ".", directory)
-    def _rcs_commit(self, commitfile, allow_empty=False):
+    def _vcs_commit(self, commitfile, allow_empty=False):
         args = ["commit", "--file", commitfile]
         if allow_empty == True:
             args.append("--unchanged")
@@ -83,9 +87,9 @@ class Bzr(RCS):
                 strings = ["ERROR: no changes to commit.", # bzr 1.3.1
                            "ERROR: No changes to commit."] # bzr 1.15.1
                 if self._u_any_in_string(strings, error) == True:
-                    raise rcs.EmptyCommit()
+                    raise vcs.EmptyCommit()
                 else:
-                    raise rcs.CommandError(args, status, error)
+                    raise vcs.CommandError(args, status, stdout="", stderr=error)
         revision = None
         revline = re.compile("Committed revision (.*)[.]")
         match = revline.search(error)
@@ -93,9 +97,17 @@ class Bzr(RCS):
         assert len(match.groups()) == 1
         revision = match.groups()[0]
         return revision
+    def _vcs_revision_id(self, index):
+        status,output,error = self._u_invoke_client("revno")
+        current_revision = int(output)
+        if index >= current_revision or index < -current_revision:
+            return None
+        if index >= 0:
+            return str(index+1) # bzr commit 0 is the empty tree.
+        return str(current_revision+index+1)
 
     
-rcs.make_rcs_testcase_subclasses(Bzr, sys.modules[__name__])
+vcs.make_vcs_testcase_subclasses(Bzr, sys.modules[__name__])
 
 unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
 suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/cmdutil.py b/interfaces/web/Bugs-Everywhere-Web/libbe/cmdutil.py
index 853a75a..9b64142 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/cmdutil.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/cmdutil.py
@@ -15,6 +15,11 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Define assorted utilities to make command-line handling easier.
+"""
+
 import glob
 import optparse
 import os
@@ -70,10 +75,11 @@ def get_command(command_name):
     return cmd
 
 
-def execute(cmd, args):
+def execute(cmd, args, manipulate_encodings=True):
     enc = encoding.get_encoding()
     cmd = get_command(cmd)
-    ret = cmd.execute([a.decode(enc) for a in args])
+    ret = cmd.execute([a.decode(enc) for a in args],
+                      manipulate_encodings=manipulate_encodings)
     if ret == None:
         ret = 0
     return ret
@@ -206,6 +212,15 @@ def underlined(instring):
     
     return "%s\n%s" % (instring, "="*len(instring))
 
+def bug_from_shortname(bdir, shortname):
+    """
+    Exception translation for the command-line interface.
+    """
+    try:
+        bug = bdir.bug_from_shortname(shortname)
+    except (bugdir.MultipleBugMatches, bugdir.NoBugMatches), e:
+        raise UserError(e.message)
+    return bug
 
 def _test():
     import doctest
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/comment.py b/interfaces/web/Bugs-Everywhere-Web/libbe/comment.py
index 3249e8b..41bc7e6 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/comment.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/comment.py
@@ -16,6 +16,11 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Define the Comment class for representing bug comments.
+"""
+
 import base64
 import os
 import os.path
@@ -61,6 +66,11 @@ class MissingReference(ValueError):
         self.reference = comment.in_reply_to
         self.comment = comment
 
+class DiskAccessRequired (Exception):
+    def __init__(self, goal):
+        msg = "Cannot %s without accessing the disk" % goal
+        Exception.__init__(self, msg)
+
 INVALID_UUID = "!!~~\n INVALID-UUID \n~~!!"
 
 def list_to_root(comments, bug, root=None,
@@ -115,8 +125,10 @@ def loadComments(bug, load_full=False):
     Set load_full=True when you want to load the comment completely
     from disk *now*, rather than waiting and lazy loading as required.
     """
+    if bug.sync_with_disk == False:
+        raise DiskAccessRequired("load comments")
     path = bug.get_path("comments")
-    if not os.path.isdir(path):
+    if not os.path.exists(path):
         return Comment(bug, uuid=INVALID_UUID)
     comments = []
     for uuid in os.listdir(path):
@@ -131,6 +143,8 @@ def loadComments(bug, load_full=False):
     return list_to_root(comments, bug)
 
 def saveComments(bug):
+    if bug.sync_with_disk == False:
+        raise DiskAccessRequired("save comments")
     for comment in bug.comment_root.traverse():
         comment.save()
 
@@ -162,9 +176,9 @@ class Comment(Tree, settings_object.SavedSettingsObject):
                          doc="Alternate ID for linking imported comments.  Internally comments are linked (via In-reply-to) to the parent's UUID.  However, these UUIDs are generated internally, so Alt-id is provided as a user-controlled linking target.")
     def alt_id(): return {}
 
-    @_versioned_property(name="From",
+    @_versioned_property(name="Author",
                          doc="The author of the comment")
-    def From(): return {}
+    def author(): return {}
 
     @_versioned_property(name="In-reply-to",
                          doc="UUID for parent comment or bug")
@@ -178,28 +192,28 @@ class Comment(Tree, settings_object.SavedSettingsObject):
 
     @_versioned_property(name="Date",
                          doc="An RFC 2822 timestamp for comment creation")
-    def time_string(): return {}
+    def date(): return {}
 
     def _get_time(self):
-        if self.time_string == None:
+        if self.date == None:
             return None
-        return utility.str_to_time(self.time_string)
+        return utility.str_to_time(self.date)
     def _set_time(self, value):
-        self.time_string = utility.time_to_str(value)
+        self.date = utility.time_to_str(value)
     time = property(fget=_get_time,
                     fset=_set_time,
-                    doc="An integer version of .time_string")
+                    doc="An integer version of .date")
 
     def _get_comment_body(self):
-        if self.rcs != None and self.sync_with_disk == True:
-            import rcs
+        if self.vcs != None and self.sync_with_disk == True:
+            import vcs
             binary = not self.content_type.startswith("text/")
-            return self.rcs.get_file_contents(self.get_path("body"), binary=binary)
+            return self.vcs.get_file_contents(self.get_path("body"), binary=binary)
     def _set_comment_body(self, old=None, new=None, force=False):
-        if (self.rcs != None and self.sync_with_disk == True) or force==True:
+        if (self.vcs != None and self.sync_with_disk == True) or force==True:
             assert new != None, "Can't save empty comment"
             binary = not self.content_type.startswith("text/")
-            self.rcs.set_file_contents(self.get_path("body"), new, binary=binary)
+            self.vcs.set_file_contents(self.get_path("body"), new, binary=binary)
 
     @Property
     @change_hook_property(hook=_set_comment_body)
@@ -208,15 +222,15 @@ class Comment(Tree, settings_object.SavedSettingsObject):
     @doc_property(doc="The meat of the comment")
     def body(): return {}
 
-    def _get_rcs(self):
-        if hasattr(self.bug, "rcs"):
-            return self.bug.rcs
+    def _get_vcs(self):
+        if hasattr(self.bug, "vcs"):
+            return self.bug.vcs
 
     @Property
-    @cached_property(generator=_get_rcs)
-    @local_property("rcs")
+    @cached_property(generator=_get_vcs)
+    @local_property("vcs")
     @doc_property(doc="A revision control system instance.")
-    def rcs(): return {}
+    def vcs(): return {}
 
     def _extra_strings_check_fn(value):
         return utility.iterable_full_of_strings(value, \
@@ -257,13 +271,29 @@ class Comment(Tree, settings_object.SavedSettingsObject):
             if uuid == None:
                 self.uuid = uuid_gen()
             self.time = int(time.time()) # only save to second precision
-            if self.rcs != None:
-                self.From = self.rcs.get_user_id()
+            if self.vcs != None:
+                self.author = self.vcs.get_user_id()
             self.in_reply_to = in_reply_to
             self.body = body
 
-    def set_sync_with_disk(self, value):
-        self.sync_with_disk = True
+    def __cmp__(self, other):
+        return cmp_full(self, other)
+
+    def __str__(self):
+        """
+        >>> comm = Comment(bug=None, body="Some insightful remarks")
+        >>> comm.uuid = "com-1"
+        >>> comm.date = "Thu, 20 Nov 2008 15:55:11 +0000"
+        >>> comm.author = "Jane Doe <jdoe@example.com>"
+        >>> print comm
+        --------- Comment ---------
+        Name: com-1
+        From: Jane Doe <jdoe@example.com>
+        Date: Thu, 20 Nov 2008 15:55:11 +0000
+        <BLANKLINE>
+        Some insightful remarks
+        """
+        return self.string()
 
     def traverse(self, *args, **kwargs):
         """Avoid working with the possible dummy root comment"""
@@ -272,6 +302,8 @@ class Comment(Tree, settings_object.SavedSettingsObject):
                 continue
             yield comment
 
+    # serializing methods
+
     def _setting_attr_string(self, setting):
         value = getattr(self, setting)
         if value == None:
@@ -282,12 +314,12 @@ class Comment(Tree, settings_object.SavedSettingsObject):
         """
         >>> comm = Comment(bug=None, body="Some\\ninsightful\\nremarks\\n")
         >>> comm.uuid = "0123"
-        >>> comm.time_string = "Thu, 01 Jan 1970 00:00:00 +0000"
+        >>> comm.date = "Thu, 01 Jan 1970 00:00:00 +0000"
         >>> print comm.xml(indent=2, shortname="com-1")
           <comment>
             <uuid>0123</uuid>
             <short-name>com-1</short-name>
-            <from></from>
+            <author></author>
             <date>Thu, 01 Jan 1970 00:00:00 +0000</date>
             <content-type>text/plain</content-type>
             <body>Some
@@ -309,8 +341,8 @@ class Comment(Tree, settings_object.SavedSettingsObject):
                 ("alt-id", self.alt_id),
                 ("short-name", shortname),
                 ("in-reply-to", self.in_reply_to),
-                ("from", self._setting_attr_string("From")),
-                ("date", self.time_string),
+                ("author", self._setting_attr_string("author")),
+                ("date", self.date),
                 ("content-type", self.content_type),
                 ("body", body)]
         lines = ["<comment>"]
@@ -328,11 +360,11 @@ class Comment(Tree, settings_object.SavedSettingsObject):
         <alt-id> fields.
         >>> commA = Comment(bug=None, body="Some\\ninsightful\\nremarks\\n")
         >>> commA.uuid = "0123"
-        >>> commA.time_string = "Thu, 01 Jan 1970 00:00:00 +0000"
+        >>> commA.date = "Thu, 01 Jan 1970 00:00:00 +0000"
         >>> xml = commA.xml(shortname="com-1")
         >>> commB = Comment()
         >>> commB.from_xml(xml)
-        >>> attrs=['uuid','alt_id','in_reply_to','From','time_string','content_type','body']
+        >>> attrs=['uuid','alt_id','in_reply_to','author','date','content_type','body']
         >>> for attr in attrs: # doctest: +ELLIPSIS
         ...     if getattr(commB, attr) != getattr(commA, attr):
         ...         estr = "Mismatch on %s: '%s' should be '%s'"
@@ -342,15 +374,15 @@ class Comment(Tree, settings_object.SavedSettingsObject):
         Mismatch on alt_id: '0123' should be 'None'
         >>> print commB.alt_id
         0123
-        >>> commA.From
-        >>> commB.From
+        >>> commA.author
+        >>> commB.author
         """
         if type(xml_string) == types.UnicodeType:
             xml_string = xml_string.strip().encode("unicode_escape")
         comment = ElementTree.XML(xml_string)
         if comment.tag != "comment":
             raise InvalidXML(comment, "root element must be <comment>")
-        tags=['uuid','alt-id','in-reply-to','from','date','content-type','body']
+        tags=['uuid','alt-id','in-reply-to','author','date','content-type','body']
         uuid = None
         body = None
         for child in comment.getchildren():
@@ -368,10 +400,6 @@ class Comment(Tree, settings_object.SavedSettingsObject):
                 if child.tag == "body":
                     body = text
                     continue # don't set the bug's body yet.
-                elif child.tag == 'from':
-                    attr_name = "From"
-                elif child.tag == 'date':
-                    attr_name = 'time_string'
                 else:
                     attr_name = child.tag.replace('-','_')
                 setattr(self, attr_name, text)
@@ -389,7 +417,7 @@ class Comment(Tree, settings_object.SavedSettingsObject):
     def string(self, indent=0, shortname=None):
         """
         >>> comm = Comment(bug=None, body="Some\\ninsightful\\nremarks\\n")
-        >>> comm.time_string = "Thu, 01 Jan 1970 00:00:00 +0000"
+        >>> comm.date = "Thu, 01 Jan 1970 00:00:00 +0000"
         >>> print comm.string(indent=2, shortname="com-1")
           --------- Comment ---------
           Name: com-1
@@ -405,8 +433,8 @@ class Comment(Tree, settings_object.SavedSettingsObject):
         lines = []
         lines.append("--------- Comment ---------")
         lines.append("Name: %s" % shortname)
-        lines.append("From: %s" % (self._setting_attr_string("From")))
-        lines.append("Date: %s" % self.time_string)
+        lines.append("From: %s" % (self._setting_attr_string("author")))
+        lines.append("Date: %s" % self.date)
         lines.append("")
         if self.content_type.startswith("text/"):
             lines.extend((self.body or "").splitlines())
@@ -417,78 +445,6 @@ class Comment(Tree, settings_object.SavedSettingsObject):
         sep = '\n' + istring
         return istring + sep.join(lines).rstrip('\n')
 
-    def __str__(self):
-        """
-        >>> comm = Comment(bug=None, body="Some insightful remarks")
-        >>> comm.uuid = "com-1"
-        >>> comm.time_string = "Thu, 20 Nov 2008 15:55:11 +0000"
-        >>> comm.From = "Jane Doe <jdoe@example.com>"
-        >>> print comm
-        --------- Comment ---------
-        Name: com-1
-        From: Jane Doe <jdoe@example.com>
-        Date: Thu, 20 Nov 2008 15:55:11 +0000
-        <BLANKLINE>
-        Some insightful remarks
-        """
-        return self.string()
-
-    def get_path(self, name=None):
-        my_dir = os.path.join(self.bug.get_path("comments"), self.uuid)
-        if name is None:
-            return my_dir
-        assert name in ["values", "body"]
-        return os.path.join(my_dir, name)
-
-    def load_settings(self):
-        self.settings = mapfile.map_load(self.rcs, self.get_path("values"))
-        self._setup_saved_settings()
-
-    def save_settings(self):
-        self.rcs.mkdir(self.get_path())
-        path = self.get_path("values")
-        mapfile.map_save(self.rcs, path, self._get_saved_settings())
-
-    def save(self):
-        """
-        Save any loaded contents to disk.
-        
-        However, if self.sync_with_disk = True, then any changes are
-        automatically written to disk as soon as they happen, so
-        calling this method will just waste time (unless something
-        else has been messing with your on-disk files).
-        """
-        assert self.body != None, "Can't save blank comment"
-        self.save_settings()
-        self._set_comment_body(new=self.body, force=True)
-
-    def remove(self):
-        for comment in self.traverse():
-            path = comment.get_path()
-            self.rcs.recursive_remove(path)
-
-    def add_reply(self, reply, allow_time_inversion=False):
-        if self.uuid != INVALID_UUID:
-            reply.in_reply_to = self.uuid
-        self.append(reply)
-        #raise Exception, "adding reply \n%s\n%s" % (self, reply)
-
-    def new_reply(self, body=None):
-        """
-        >>> comm = Comment(bug=None, body="Some insightful remarks")
-        >>> repA = comm.new_reply("Critique original comment")
-        >>> repB = repA.new_reply("Begin flamewar :p")
-        >>> repB.in_reply_to == repA.uuid
-        True
-        """
-        reply = Comment(self.bug, body=body)
-        if self.bug != None:
-            reply.set_sync_with_disk(self.bug.sync_with_disk)
-        if reply.sync_with_disk == True:
-            reply.save()
-        self.add_reply(reply)
-        return reply
-
     def string_thread(self, string_method_name="string", name_map={},
                       indent=0, flatten=True,
                       auto_name_map=False, bug_shortname=None):
@@ -506,7 +462,7 @@ class Comment(Tree, settings_object.SavedSettingsObject):
           name_map = {}
           for shortname,comment in comm.comment_shortnames(bug_shortname):
               name_map[comment.uuid] = shortname
-          comm.sort(key=lambda c : c.From) # your sort
+          comm.sort(key=lambda c : c.author) # your sort
           comm.string_thread(name_map=name_map)
 
         >>> a = Comment(bug=None, uuid="a", body="Insightful remarks")
@@ -593,6 +549,77 @@ class Comment(Tree, settings_object.SavedSettingsObject):
                                   indent=indent, auto_name_map=auto_name_map,
                                   bug_shortname=bug_shortname)
 
+    # methods for saving/loading/acessing settings and properties.
+
+    def get_path(self, *args):
+        dir = os.path.join(self.bug.get_path("comments"), self.uuid)
+        if len(args) == 0:
+            return dir
+        assert args[0] in ["values", "body"], str(args)
+        return os.path.join(dir, *args)
+
+    def set_sync_with_disk(self, value):
+        self.sync_with_disk = value
+
+    def load_settings(self):
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("load settings")
+        self.settings = mapfile.map_load(self.vcs, self.get_path("values"))
+        self._setup_saved_settings()
+
+    def save_settings(self):
+        if self.sync_with_disk == False:
+            raise DiskAccessRequired("save settings")
+        self.vcs.mkdir(self.get_path())
+        path = self.get_path("values")
+        mapfile.map_save(self.vcs, path, self._get_saved_settings())
+
+    def save(self):
+        """
+        Save any loaded contents to disk.
+        
+        However, if self.sync_with_disk = True, then any changes are
+        automatically written to disk as soon as they happen, so
+        calling this method will just waste time (unless something
+        else has been messing with your on-disk files).
+        """
+        sync_with_disk = self.sync_with_disk
+        if sync_with_disk == False:
+            self.set_sync_with_disk(True)
+        assert self.body != None, "Can't save blank comment"
+        self.save_settings()
+        self._set_comment_body(new=self.body, force=True)
+        if sync_with_disk == False:
+            self.set_sync_with_disk(False)
+
+    def remove(self):
+        if self.sync_with_disk == False and self.uuid != INVALID_UUID:
+            raise DiskAccessRequired("remove")
+        for comment in self.traverse():
+            path = comment.get_path()
+            self.vcs.recursive_remove(path)
+
+    def add_reply(self, reply, allow_time_inversion=False):
+        if self.uuid != INVALID_UUID:
+            reply.in_reply_to = self.uuid
+        self.append(reply)
+
+    def new_reply(self, body=None):
+        """
+        >>> comm = Comment(bug=None, body="Some insightful remarks")
+        >>> repA = comm.new_reply("Critique original comment")
+        >>> repB = repA.new_reply("Begin flamewar :p")
+        >>> repB.in_reply_to == repA.uuid
+        True
+        """
+        reply = Comment(self.bug, body=body)
+        if self.bug != None:
+            reply.set_sync_with_disk(self.bug.sync_with_disk)
+        if reply.sync_with_disk == True:
+            reply.save()
+        self.add_reply(reply)
+        return reply
+
     def comment_shortnames(self, bug_shortname=None):
         """
         Iterate through (id, comment) pairs, in time order.
@@ -659,4 +686,59 @@ class Comment(Tree, settings_object.SavedSettingsObject):
                 return comment
         raise KeyError(uuid)
 
+def cmp_attr(comment_1, comment_2, attr, invert=False):
+    """
+    Compare a general attribute between two comments using the conventional
+    comparison rule for that attribute type.  If invert == True, sort
+    *against* that convention.
+    >>> attr="author"
+    >>> commentA = Comment()
+    >>> commentB = Comment()
+    >>> commentA.author = "John Doe"
+    >>> commentB.author = "Jane Doe"
+    >>> cmp_attr(commentA, commentB, attr) > 0
+    True
+    >>> cmp_attr(commentA, commentB, attr, invert=True) < 0
+    True
+    >>> commentB.author = "John Doe"
+    >>> cmp_attr(commentA, commentB, attr) == 0
+    True
+    """
+    if not hasattr(comment_2, attr) :
+        return 1
+    val_1 = getattr(comment_1, attr)
+    val_2 = getattr(comment_2, attr)
+    if val_1 == None: val_1 = None
+    if val_2 == None: val_2 = None
+    
+    if invert == True :
+        return -cmp(val_1, val_2)
+    else :
+        return cmp(val_1, val_2)
+
+# alphabetical rankings (a < z)
+cmp_uuid = lambda comment_1, comment_2 : cmp_attr(comment_1, comment_2, "uuid")
+cmp_author = lambda comment_1, comment_2 : cmp_attr(comment_1, comment_2, "author")
+cmp_in_reply_to = lambda comment_1, comment_2 : cmp_attr(comment_1, comment_2, "in_reply_to")
+cmp_content_type = lambda comment_1, comment_2 : cmp_attr(comment_1, comment_2, "content_type")
+cmp_body = lambda comment_1, comment_2 : cmp_attr(comment_1, comment_2, "body")
+# chronological rankings (newer < older)
+cmp_time = lambda comment_1, comment_2 : cmp_attr(comment_1, comment_2, "time", invert=True)
+
+DEFAULT_CMP_FULL_CMP_LIST = \
+    (cmp_time, cmp_author, cmp_content_type, cmp_body, cmp_in_reply_to,
+     cmp_uuid)
+
+class CommentCompoundComparator (object):
+    def __init__(self, cmp_list=DEFAULT_CMP_FULL_CMP_LIST):
+        self.cmp_list = cmp_list
+    def __call__(self, comment_1, comment_2):
+        for comparison in self.cmp_list :
+            val = comparison(comment_1, comment_2)
+            if val != 0 :
+                return val
+        return 0
+        
+cmp_full = CommentCompoundComparator()
+
 suite = doctest.DocTestSuite()
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/config.py b/interfaces/web/Bugs-Everywhere-Web/libbe/config.py
index 5e343b9..fb5a028 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/config.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/config.py
@@ -14,6 +14,11 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Create, save, and load the per-user config file at path().
+"""
+
 import ConfigParser
 import codecs
 import locale
@@ -21,6 +26,7 @@ import os.path
 import sys
 import doctest
 
+
 default_encoding = sys.getfilesystemencoding() or locale.getpreferredencoding()
 
 def path():
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/darcs.py b/interfaces/web/Bugs-Everywhere-Web/libbe/darcs.py
index e7132c0..16005f2 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/darcs.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/darcs.py
@@ -14,31 +14,40 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+"""
+Darcs backend.
+"""
+
 import codecs
 import os
 import re
 import sys
-import unittest
+try: # import core module, Python >= 2.5
+    from xml.etree import ElementTree
+except ImportError: # look for non-core module
+    from elementtree import ElementTree
+from xml.sax.saxutils import unescape
 import doctest
+import unittest
+
+import vcs
 
-import rcs
-from rcs import RCS
 
 def new():
     return Darcs()
 
-class Darcs(RCS):
+class Darcs(vcs.VCS):
     name="darcs"
     client="darcs"
     versioned=True
-    def _rcs_help(self):
+    def _vcs_help(self):
         status,output,error = self._u_invoke_client("--help")
         return output
-    def _rcs_detect(self, path):
+    def _vcs_detect(self, path):
         if self._u_search_parent_directories(path, "_darcs") != None :
             return True
         return False 
-    def _rcs_root(self, path):
+    def _vcs_root(self, path):
         """Find the root of the deepest repository containing path."""
         # Assume that nothing funny is going on; in particular, that we aren't
         # dealing with a bare repo.
@@ -48,9 +57,9 @@ class Darcs(RCS):
         if darcs_dir == None:
             return None
         return os.path.dirname(darcs_dir)
-    def _rcs_init(self, path):
+    def _vcs_init(self, path):
         self._u_invoke_client("init", directory=path)
-    def _rcs_get_user_id(self):
+    def _vcs_get_user_id(self):
         # following http://darcs.net/manual/node4.html#SECTION00410030000000000000
         # as of June 29th, 2009
         if self.rootdir == None:
@@ -65,32 +74,32 @@ class Darcs(RCS):
             if env_variable in os.environ:
                 return os.environ[env_variable]
         return None
-    def _rcs_set_user_id(self, value):
+    def _vcs_set_user_id(self, value):
         if self.rootdir == None:
             self.root(".")
             if self.rootdir == None:
-                raise rcs.SettingIDnotSupported
+                raise vcs.SettingIDnotSupported
         author_path = os.path.join(self.rootdir, "_darcs", "prefs", "author")
         f = codecs.open(author_path, "w", self.encoding)
         f.write(value)
         f.close()
-    def _rcs_add(self, path):
+    def _vcs_add(self, path):
         if os.path.isdir(path):
             return
         self._u_invoke_client("add", path)
-    def _rcs_remove(self, path):
+    def _vcs_remove(self, path):
         if not os.path.isdir(self._u_abspath(path)):
             os.remove(os.path.join(self.rootdir, path)) # darcs notices removal
-    def _rcs_update(self, path):
+    def _vcs_update(self, path):
         pass # darcs notices changes
-    def _rcs_get_file_contents(self, path, revision=None, binary=False):
+    def _vcs_get_file_contents(self, path, revision=None, binary=False):
         if revision == None:
-            return RCS._rcs_get_file_contents(self, path, revision,
+            return vcs.VCS._vcs_get_file_contents(self, path, revision,
                                               binary=binary)
         else:
             try:
                 return self._u_invoke_client("show", "contents", "--patch", revision, path)
-            except rcs.CommandError:
+            except vcs.CommandError:
                 # Darcs versions < 2.0.0pre2 lack the "show contents" command
 
                 status,output,error = self._u_invoke_client("diff", "--unified",
@@ -113,7 +122,7 @@ class Darcs(RCS):
                 status,output,error = self._u_invoke(args, stdin=target_patch)
 
                 if os.path.exists(os.path.join(self.rootdir, path)) == True:
-                    contents = RCS._rcs_get_file_contents(self, path,
+                    contents = vcs.VCS._vcs_get_file_contents(self, path,
                                                           binary=binary)
                 else:
                     contents = ""
@@ -123,41 +132,53 @@ class Darcs(RCS):
                 status,output,error = self._u_invoke(args, stdin=target_patch)
                 args=["patch", path]
                 status,output,error = self._u_invoke(args, stdin=major_patch)
-                current_contents = RCS._rcs_get_file_contents(self, path,
+                current_contents = vcs.VCS._vcs_get_file_contents(self, path,
                                                               binary=binary)
                 return contents
-    def _rcs_duplicate_repo(self, directory, revision=None):
+    def _vcs_duplicate_repo(self, directory, revision=None):
         if revision==None:
-            RCS._rcs_duplicate_repo(self, directory, revision)
+            vcs.VCS._vcs_duplicate_repo(self, directory, revision)
         else:
             self._u_invoke_client("put", "--to-patch", revision, directory)
-    def _rcs_commit(self, commitfile, allow_empty=False):
+    def _vcs_commit(self, commitfile, allow_empty=False):
         id = self.get_user_id()
         if '@' not in id:
             id = "%s <%s@invalid.com>" % (id, id)
         args = ['record', '--all', '--author', id, '--logfile', commitfile]
         status,output,error = self._u_invoke_client(*args)
         empty_strings = ["No changes!"]
-        revision = None
         if self._u_any_in_string(empty_strings, output) == True:
             if allow_empty == False:
-                raise rcs.EmptyCommit()
-            else: # we need a extra call to get the current revision
-                args = ["changes", "--last=1", "--xml"]
-                status,output,error = self._u_invoke_client(*args)
-                revline = re.compile("[ \t]*<name>(.*)</name>")
-                # note that darcs does _not_ make an empty revision.
-                # this returns the last non-empty revision id...
+                raise vcs.EmptyCommit()
+            # note that darcs does _not_ make an empty revision.
+            # this returns the last non-empty revision id...
+            revision = self._vcs_revision_id(-1)
         else:
             revline = re.compile("Finished recording patch '(.*)'")
-        match = revline.search(output)
-        assert match != None, output+error
-        assert len(match.groups()) == 1
-        revision = match.groups()[0]
+            match = revline.search(output)
+            assert match != None, output+error
+            assert len(match.groups()) == 1
+            revision = match.groups()[0]
         return revision
-
+    def _vcs_revision_id(self, index):
+        status,output,error = self._u_invoke_client("changes", "--xml")
+        revisions = []
+        xml_str = output.encode("unicode_escape").replace(r"\n", "\n")
+        element = ElementTree.XML(xml_str)
+        assert element.tag == "changelog", element.tag
+        for patch in element.getchildren():
+            assert patch.tag == "patch", patch.tag
+            for child in patch.getchildren():
+                if child.tag == "name":
+                    text = unescape(unicode(child.text).decode("unicode_escape").strip())
+                    revisions.append(text)
+        revisions.reverse()
+        try:
+            return revisions[index]
+        except IndexError:
+            return None
     
-rcs.make_rcs_testcase_subclasses(Darcs, sys.modules[__name__])
+vcs.make_vcs_testcase_subclasses(Darcs, sys.modules[__name__])
 
 unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
 suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/diff.py b/interfaces/web/Bugs-Everywhere-Web/libbe/diff.py
index ba48efc..9253a23 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/diff.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/diff.py
@@ -14,112 +14,406 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-"""Compare two bug trees"""
-from libbe import cmdutil, bugdir, bug
-from libbe.utility import time_to_str
+
+"""Compare two bug trees."""
+
+import difflib
 import doctest
 
-def bug_diffs(old_bugdir, new_bugdir):
-    added = []
-    removed = []
-    modified = []
-    for uuid in old_bugdir.list_uuids():
-        old_bug = old_bugdir.bug_from_uuid(uuid)
-        try:
-            new_bug = new_bugdir.bug_from_uuid(uuid)
-            old_bug.load_comments()
-            new_bug.load_comments()
-            if old_bug != new_bug:
-                modified.append((old_bug, new_bug))
-        except KeyError:
-            removed.append(old_bug)
-    for uuid in new_bugdir.list_uuids():
-        if not old_bugdir.has_bug(uuid):
-            new_bug = new_bugdir.bug_from_uuid(uuid)
-            added.append(new_bug)
-    return (removed, modified, added)
+from libbe import bugdir, bug, settings_object, tree
+from libbe.utility import time_to_str
 
-def diff_report(bug_diffs_data, old_bugdir, new_bugdir):
-    bugs_removed,bugs_modified,bugs_added = bug_diffs_data
-    def modified_cmp(left, right):
-        return bug.cmp_severity(left[1], right[1])
 
-    bugs_added.sort(bug.cmp_severity)
-    bugs_removed.sort(bug.cmp_severity)
-    bugs_modified.sort(modified_cmp)
-    lines = []
-    
-    if old_bugdir.settings != new_bugdir.settings:
-        bugdir_settings = sorted(new_bugdir.settings_properties)
-        bugdir_settings.remove("rcs_name") # tweaked by bugdir.duplicate_bugdir
-        change_list = change_lines(old_bugdir, new_bugdir, bugdir_settings)
-        if len(change_list) >  0:
-            lines.append("Modified bug directory:")
-            change_strings = ["%s: %s -> %s" % f for f in change_list]
-            lines.extend(change_strings)
-            lines.append("")
-    if len(bugs_added) > 0:
-        lines.append("New bug reports:")
-        for bg in bugs_added:
-            lines.extend(bg.string(shortlist=True).splitlines())
-        lines.append("")
-    if len(bugs_modified) > 0:
-        printed = False
-        for old_bug, new_bug in bugs_modified:
-            change_str = bug_changes(old_bug, new_bug)
-            if change_str is None:
-                continue
-            if not printed:
-                printed = True
-                lines.append("Modified bug reports:")
-            lines.extend(change_str.splitlines())
-        if printed == True:
-            lines.append("")
-    if len(bugs_removed) > 0:
-        lines.append("Removed bug reports:")
-        for bg in bugs_removed:
-            lines.extend(bg.string(shortlist=True).splitlines())
-        lines.append("")
-    
-    return "\n".join(lines).rstrip("\n")
+class DiffTree (tree.Tree):
+    """
+    A tree holding difference data for easy report generation.
+    >>> bugdir = DiffTree("bugdir")
+    >>> bdsettings = DiffTree("settings", data="target: None -> 1.0")
+    >>> bugdir.append(bdsettings)
+    >>> bugs = DiffTree("bugs", "bug-count: 5 -> 6")
+    >>> bugdir.append(bugs)
+    >>> new = DiffTree("new", "new bugs: ABC, DEF")
+    >>> bugs.append(new)
+    >>> rem = DiffTree("rem", "removed bugs: RST, UVW")
+    >>> bugs.append(rem)
+    >>> print bugdir.report_string()
+    target: None -> 1.0
+    bug-count: 5 -> 6
+      new bugs: ABC, DEF
+      removed bugs: RST, UVW
+    >>> print "\\n".join(bugdir.paths())
+    bugdir
+    bugdir/settings
+    bugdir/bugs
+    bugdir/bugs/new
+    bugdir/bugs/rem
+    >>> bugdir.child_by_path("/") == bugdir
+    True
+    >>> bugdir.child_by_path("/bugs") == bugs
+    True
+    >>> bugdir.child_by_path("/bugs/rem") == rem
+    True
+    >>> bugdir.child_by_path("bugdir") == bugdir
+    True
+    >>> bugdir.child_by_path("bugdir/") == bugdir
+    True
+    >>> bugdir.child_by_path("bugdir/bugs") == bugs
+    True
+    >>> bugdir.child_by_path("/bugs").masked = True
+    >>> print bugdir.report_string()
+    target: None -> 1.0
+    """
+    def __init__(self, name, data=None, data_part_fn=str,
+                 requires_children=False, masked=False):
+        tree.Tree.__init__(self)
+        self.name = name
+        self.data = data
+        self.data_part_fn = data_part_fn
+        self.requires_children = requires_children
+        self.masked = masked
+    def paths(self, parent_path=None):
+        paths = []
+        if parent_path == None:
+            path = self.name
+        else:
+            path = "%s/%s" % (parent_path, self.name)
+        paths.append(path)
+        for child in self:
+            paths.extend(child.paths(path))
+        return paths
+    def child_by_path(self, path):
+        if hasattr(path, "split"): # convert string path to a list of names
+            names = path.split("/")
+            if names[0] == "":
+                names[0] = self.name # replace root with self
+            if len(names) > 1 and names[-1] == "":
+                names = names[:-1] # strip empty tail
+        else: # it was already an array
+            names = path
+        assert len(names) > 0, path
+        if names[0] == self.name:
+            if len(names) == 1:
+                return self
+            for child in self:
+                if names[1] == child.name:
+                    return child.child_by_path(names[1:])
+        if len(names) == 1:
+            raise KeyError, "%s doesn't match '%s'" % (names, self.name)
+        raise KeyError, "%s points to child not in %s" % (names, [c.name for c in self])
+    def report_string(self):
+        return "\n".join(self.report())
+    def report(self, root=None, parent=None, depth=0):
+        if root == None:
+            root = self.make_root()
+        if self.masked == True:
+            return None
+        data_part = self.data_part(depth)
+        if self.requires_children == True and len(self) == 0:
+            pass
+        else:
+            self.join(root, parent, data_part)
+            if data_part != None:
+                depth += 1
+        for child in self:
+            child.report(root, self, depth)
+        return root
+    def make_root(self):
+        return []
+    def join(self, root, parent, data_part):
+        if data_part != None:
+            root.append(data_part)
+    def data_part(self, depth, indent=True):
+        if self.data == None:
+            return None
+        if hasattr(self, "_cached_data_part"):
+            return self._cached_data_part
+        data_part = self.data_part_fn(self.data)
+        if indent == True:
+            data_part_lines = data_part.splitlines()
+            indent = "  "*(depth)
+            line_sep = "\n"+indent
+            data_part = indent+line_sep.join(data_part_lines)
+        self._cached_data_part = data_part
+        return data_part
 
-def change_lines(old, new, attributes):
-    change_list = []    
-    for attr in attributes:
-        old_attr = getattr(old, attr)
-        new_attr = getattr(new, attr)
-        if old_attr != new_attr:
-            change_list.append((attr, old_attr, new_attr))
-    if len(change_list) >= 0:
-        return change_list
-    else:
+class Diff (object):
+    """
+    Difference tree generator for BugDirs.
+    >>> import copy
+    >>> bd = bugdir.SimpleBugDir(sync_with_disk=False)
+    >>> bd.user_id = "John Doe <j@doe.com>"
+    >>> bd_new = copy.deepcopy(bd)
+    >>> bd_new.target = "1.0"
+    >>> a = bd_new.bug_from_uuid("a")
+    >>> rep = a.comment_root.new_reply("I'm closing this bug")
+    >>> rep.uuid = "acom"
+    >>> rep.date = "Thu, 01 Jan 1970 00:00:00 +0000"
+    >>> a.status = "closed"
+    >>> b = bd_new.bug_from_uuid("b")
+    >>> bd_new.remove_bug(b)
+    >>> c = bd_new.new_bug("c", "Bug C")
+    >>> d = Diff(bd, bd_new)
+    >>> r = d.report_tree()
+    >>> print "\\n".join(r.paths())
+    bugdir
+    bugdir/settings
+    bugdir/bugs
+    bugdir/bugs/new
+    bugdir/bugs/new/c
+    bugdir/bugs/rem
+    bugdir/bugs/rem/b
+    bugdir/bugs/mod
+    bugdir/bugs/mod/a
+    bugdir/bugs/mod/a/settings
+    bugdir/bugs/mod/a/comments
+    bugdir/bugs/mod/a/comments/new
+    bugdir/bugs/mod/a/comments/new/acom
+    bugdir/bugs/mod/a/comments/rem
+    bugdir/bugs/mod/a/comments/mod
+    >>> print r.report_string()
+    Changed bug directory settings:
+      target: None -> 1.0
+    New bugs:
+      c:om: Bug C
+    Removed bugs:
+      b:cm: Bug B
+    Modified bugs:
+      a:cm: Bug A
+        Changed bug settings:
+          status: open -> closed
+        New comments:
+          from John Doe <j@doe.com> on Thu, 01 Jan 1970 00:00:00 +0000
+            I'm closing this bug...
+    >>> bd.cleanup()
+    """
+    def __init__(self, old_bugdir, new_bugdir):
+        self.old_bugdir = old_bugdir
+        self.new_bugdir = new_bugdir
+
+    # data assembly methods
+
+    def _changed_bugs(self):
+        """
+        Search for differences in all bugs between .old_bugdir and
+        .new_bugdir.  Returns
+          (added_bugs, modified_bugs, removed_bugs)
+        where added_bugs and removed_bugs are lists of added and
+        removed bugs respectively.  modified_bugs is a list of
+        (old_bug,new_bug) pairs.
+        """
+        if hasattr(self, "__changed_bugs"):
+            return self.__changed_bugs
+        added = []
+        removed = []
+        modified = []
+        for uuid in self.new_bugdir.list_uuids():
+            new_bug = self.new_bugdir.bug_from_uuid(uuid)
+            try:
+                old_bug = self.old_bugdir.bug_from_uuid(uuid)
+            except KeyError:
+                added.append(new_bug)
+            else:
+                if old_bug.sync_with_disk == True:
+                    old_bug.load_comments()
+                if new_bug.sync_with_disk == True:
+                    new_bug.load_comments()
+                if old_bug != new_bug:
+                    modified.append((old_bug, new_bug))
+        for uuid in self.old_bugdir.list_uuids():
+            if not self.new_bugdir.has_bug(uuid):
+                old_bug = self.old_bugdir.bug_from_uuid(uuid)
+                removed.append(old_bug)
+        added.sort()
+        removed.sort()
+        modified.sort(self._bug_modified_cmp)
+        self.__changed_bugs = (added, modified, removed)
+        return self.__changed_bugs
+    def _bug_modified_cmp(self, left, right):
+        return cmp(left[1], right[1])
+    def _changed_comments(self, old, new):
+        """
+        Search for differences in all loaded comments between the bugs
+        old and new.  Returns
+          (added_comments, modified_comments, removed_comments)
+        analogous to ._changed_bugs.
+        """
+        if hasattr(self, "__changed_comments"):
+            if new.uuid in self.__changed_comments:
+                return self.__changed_comments[new.uuid]
+        else:
+            self.__changed_comments = {}
+        added = []
+        removed = []
+        modified = []
+        old.comment_root.sort(key=lambda comm : comm.time)
+        new.comment_root.sort(key=lambda comm : comm.time)
+        old_comment_ids = [c.uuid for c in old.comments()]
+        new_comment_ids = [c.uuid for c in new.comments()]
+        for uuid in new_comment_ids:
+            new_comment = new.comment_from_uuid(uuid)
+            try:
+                old_comment = old.comment_from_uuid(uuid)
+            except KeyError:
+                added.append(new_comment)
+            else:
+                if old_comment != new_comment:
+                    modified.append((old_comment, new_comment))
+        for uuid in old_comment_ids:
+            if uuid not in new_comment_ids:
+                new_comment = new.comment_from_uuid(uuid)
+                removed.append(new_comment)
+        self.__changed_comments[new.uuid] = (added, modified, removed)
+        return self.__changed_comments[new.uuid]
+    def _attribute_changes(self, old, new, attributes):
+        """
+        Take two objects old and new, and compare the value of *.attr
+        for attr in the list attribute names.  Returns a list of
+          (attr_name, old_value, new_value)
+        tuples.
+        """
+        change_list = []
+        for attr in attributes:
+            old_value = getattr(old, attr)
+            new_value = getattr(new, attr)
+            if old_value != new_value:
+                change_list.append((attr, old_value, new_value))
+        if len(change_list) >= 0:
+            return change_list
         return None
+    def _settings_properties_attribute_changes(self, old, new,
+                                              hidden_properties=[]):
+        properties = sorted(new.settings_properties)
+        for p in hidden_properties:
+            properties.remove(p)
+        attributes = [settings_object.setting_name_to_attr_name(None, p)
+                      for p in properties]
+        return self._attribute_changes(old, new, attributes)
+    def _bugdir_attribute_changes(self):
+        return self._settings_properties_attribute_changes( \
+            self.old_bugdir, self.new_bugdir,
+            ["vcs_name"]) # tweaked by bugdir.duplicate_bugdir
+    def _bug_attribute_changes(self, old, new):
+        return self._settings_properties_attribute_changes(old, new)
+    def _comment_attribute_changes(self, old, new):
+        return self._settings_properties_attribute_changes(old, new)
 
-def bug_changes(old, new):
-    bug_settings = sorted(new.settings_properties)
-    change_list = change_lines(old, new, bug_settings)
-    change_strings = ["%s: %s -> %s" % f for f in change_list]
+    # report generation methods
 
-    old_comment_ids = [c.uuid for c in old.comments()]
-    new_comment_ids = [c.uuid for c in new.comments()]
-    for comment_id in new_comment_ids:
-        if comment_id not in old_comment_ids:
-            summary = comment_summary(new.comment_from_uuid(comment_id), "new")
-            change_strings.append(summary)
-    for comment_id in old_comment_ids:
-        if comment_id not in new_comment_ids:
-            summary = comment_summary(new.comment_from_uuid(comment_id),
-                                      "removed")
-            change_strings.append(summary)
+    def report_tree(self, diff_tree=DiffTree):
+        """
+        Pretty bare to make it easy to adjust to specific cases.  You
+        can pass in a DiffTree subclass via diff_tree to override the
+        default report assembly process.
+        """
+        if hasattr(self, "__report_tree"):
+            return self.__report_tree
+        bugdir_settings = sorted(self.new_bugdir.settings_properties)
+        bugdir_settings.remove("vcs_name") # tweaked by bugdir.duplicate_bugdir
+        root = diff_tree("bugdir")
+        bugdir_attribute_changes = self._bugdir_attribute_changes()
+        if len(bugdir_attribute_changes) > 0:
+            bugdir = diff_tree("settings", bugdir_attribute_changes,
+                               self.bugdir_attribute_change_string)
+            root.append(bugdir)
+        bug_root = diff_tree("bugs")
+        root.append(bug_root)
+        add,mod,rem = self._changed_bugs()
+        bnew = diff_tree("new", "New bugs:", requires_children=True)
+        bug_root.append(bnew)
+        for bug in add:
+            b = diff_tree(bug.uuid, bug, self.bug_add_string)
+            bnew.append(b)
+        brem = diff_tree("rem", "Removed bugs:", requires_children=True)
+        bug_root.append(brem)
+        for bug in rem:
+            b = diff_tree(bug.uuid, bug, self.bug_rem_string)
+            brem.append(b)
+        bmod = diff_tree("mod", "Modified bugs:", requires_children=True)
+        bug_root.append(bmod)
+        for old,new in mod:
+            b = diff_tree(new.uuid, (old,new), self.bug_mod_string)
+            bmod.append(b)
+            bug_attribute_changes = self._bug_attribute_changes(old, new)
+            if len(bug_attribute_changes) > 0:
+                bset = diff_tree("settings", bug_attribute_changes,
+                                 self.bug_attribute_change_string)
+                b.append(bset)
+            if old.summary != new.summary:
+                data = (old.summary, new.summary)
+                bsum = diff_tree("summary", data, self.bug_summary_change_string)
+                b.append(bsum)
+            cr = diff_tree("comments")
+            b.append(cr)
+            a,m,d = self._changed_comments(old, new)
+            cnew = diff_tree("new", "New comments:", requires_children=True)
+            for comment in a:
+                c = diff_tree(comment.uuid, comment, self.comment_add_string)
+                cnew.append(c)
+            crem = diff_tree("rem", "Removed comments:",requires_children=True)
+            for comment in d:
+                c = diff_tree(comment.uuid, comment, self.comment_rem_string)
+                crem.append(c)
+            cmod = diff_tree("mod","Modified comments:",requires_children=True)
+            for o,n in m:
+                c = diff_tree(n.uuid, (o,n), self.comment_mod_string)
+                cmod.append(c)
+                comm_attribute_changes = self._comment_attribute_changes(o, n)
+                if len(comm_attribute_changes) > 0:
+                    cset = diff_tree("settings", comm_attribute_changes,
+                                     self.comment_attribute_change_string)
+                if o.body != n.body:
+                    data = (o.body, n.body)
+                    cbody = diff_tree("cbody", data,
+                                      self.comment_body_change_string)
+                    c.append(cbody)
+            cr.extend([cnew, crem, cmod])
+        self.__report_tree = root
+        return self.__report_tree
 
-    if len(change_strings) == 0:
-        return None
-    return "%s\n  %s" % (new.string(shortlist=True),
-                         "  \n".join(change_strings))
+    # change data -> string methods.
+    # Feel free to play with these in subclasses.
 
+    def attribute_change_string(self, attribute_changes, indent=0):
+        indent_string = "  "*indent
+        change_strings = [u"%s: %s -> %s" % f for f in attribute_changes]
+        for i,change_string in enumerate(change_strings):
+            change_strings[i] = indent_string+change_string
+        return u"\n".join(change_strings)
+    def bugdir_attribute_change_string(self, attribute_changes):
+        return "Changed bug directory settings:\n%s" % \
+            self.attribute_change_string(attribute_changes, indent=1)
+    def bug_attribute_change_string(self, attribute_changes):
+        return "Changed bug settings:\n%s" % \
+            self.attribute_change_string(attribute_changes, indent=1)
+    def comment_attribute_change_string(self, attribute_changes):
+        return "Changed comment settings:\n%s" % \
+            self.attribute_change_string(attribute_changes, indent=1)
+    def bug_add_string(self, bug):
+        return bug.string(shortlist=True)
+    def bug_rem_string(self, bug):
+        return bug.string(shortlist=True)
+    def bug_mod_string(self, bugs):
+        old_bug,new_bug = bugs
+        return new_bug.string(shortlist=True)
+    def bug_summary_change_string(self, summaries):
+        old_summary,new_summary = summaries
+        return "summary changed:\n  %s\n  %s" % (old_summary, new_summary)
+    def _comment_summary_string(self, comment):
+        return "from %s on %s" % (comment.author, time_to_str(comment.time))
+    def comment_add_string(self, comment):
+        summary = self._comment_summary_string(comment)
+        first_line = comment.body.splitlines()[0]
+        return "%s\n  %s..." % (summary, first_line)
+    def comment_rem_string(self, comment):
+        summary = self._comment_summary_string(comment)
+        first_line = comment.body.splitlines()[0]
+        return "%s\n  %s..." % (summary, first_line)
+    def comment_mod_string(self, comments):
+        old_comment,new_comment = comments
+        return self._comment_summary_string(new_comment)
+    def comment_body_change_string(self, bodies):
+        old_body,new_body = bodies
+        return difflib.unified_diff(old_body, new_body)
 
-def comment_summary(comment, status):
-    return "%8s comment from %s on %s" % (status, comment.From, 
-                                          time_to_str(comment.time))
 
 suite = doctest.DocTestSuite()
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/editor.py b/interfaces/web/Bugs-Everywhere-Web/libbe/editor.py
index 93144b8..ec41006 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/editor.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/editor.py
@@ -15,6 +15,11 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+"""
+Define editor_string(), a function that invokes an editor to accept
+user-produced text as a string.
+"""
+
 import codecs
 import locale
 import os
@@ -22,6 +27,7 @@ import sys
 import tempfile
 import doctest
 
+
 default_encoding = sys.getfilesystemencoding() or locale.getpreferredencoding()
 
 comment_marker = u"== Anything below this line will be ignored\n"
@@ -62,7 +68,8 @@ def editor_string(comment=None, encoding=None):
     fhandle, fname = tempfile.mkstemp()
     try:
         if comment is not None:
-            os.write(fhandle, '\n'+comment_string(comment))
+            cstring = u'\n'+comment_string(comment)
+            os.write(fhandle, cstring.encode(encoding))
         os.close(fhandle)
         oldmtime = os.path.getmtime(fname)
         os.system("%s %s" % (editor, fname))
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/encoding.py b/interfaces/web/Bugs-Everywhere-Web/libbe/encoding.py
index d603602..fd513b5 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/encoding.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/encoding.py
@@ -14,16 +14,26 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Support input/output/filesystem encodings (e.g. UTF-8).
+"""
+
 import codecs
 import locale
 import sys
 import doctest
 
+
+ENCODING = None # override get_encoding() output by setting this
+
 def get_encoding():
     """
     Guess a useful input/output/filesystem encoding...  Maybe we need
     seperate encodings for input/output and filesystem?  Hmm...
     """
+    if ENCODING != None:
+        return ENCODING
     encoding = locale.getpreferredencoding() or sys.getdefaultencoding()
     if sys.platform != 'win32' or sys.version_info[:2] > (2, 3):
         encoding = locale.getlocale(locale.LC_TIME)[1] or encoding
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/git.py b/interfaces/web/Bugs-Everywhere-Web/libbe/git.py
index 2f9ffa9..3abe3b8 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/git.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/git.py
@@ -16,30 +16,34 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+"""
+Git backend.
+"""
+
 import os
 import re
 import sys
 import unittest
 import doctest
 
-import rcs
-from rcs import RCS
+import vcs
+
 
 def new():
     return Git()
 
-class Git(RCS):
+class Git(vcs.VCS):
     name="git"
     client="git"
     versioned=True
-    def _rcs_help(self):
+    def _vcs_help(self):
         status,output,error = self._u_invoke_client("--help")
         return output
-    def _rcs_detect(self, path):
+    def _vcs_detect(self, path):
         if self._u_search_parent_directories(path, ".git") != None :
             return True
         return False 
-    def _rcs_root(self, path):
+    def _vcs_root(self, path):
         """Find the root of the deepest repository containing path."""
         # Assume that nothing funny is going on; in particular, that we aren't
         # dealing with a bare repo.
@@ -50,13 +54,21 @@ class Git(RCS):
         gitdir = os.path.join(path, output.rstrip('\n'))
         dirname = os.path.abspath(os.path.dirname(gitdir))
         return dirname
-    def _rcs_init(self, path):
+    def _vcs_init(self, path):
         self._u_invoke_client("init", directory=path)
-    def _rcs_get_user_id(self):
-        status,output,error = self._u_invoke_client("config", "user.name")
-        name = output.rstrip('\n')
-        status,output,error = self._u_invoke_client("config", "user.email")
-        email = output.rstrip('\n')
+    def _vcs_get_user_id(self):
+        status,output,error = \
+            self._u_invoke_client("config", "user.name", expect=(0,1))
+        if status == 0:
+            name = output.rstrip('\n')
+        else:
+            name = ""
+        status,output,error = \
+            self._u_invoke_client("config", "user.email", expect=(0,1))
+        if status == 0:
+            email = output.rstrip('\n')
+        else:
+            email = ""
         if name != "" or email != "": # got something!
             # guess missing info, if necessary
             if name == "":
@@ -65,35 +77,35 @@ class Git(RCS):
                 email = self._u_get_fallback_email()
             return self._u_create_id(name, email)
         return None # Git has no infomation
-    def _rcs_set_user_id(self, value):
+    def _vcs_set_user_id(self, value):
         name,email = self._u_parse_id(value)
         if email != None:
             self._u_invoke_client("config", "user.email", email)
         self._u_invoke_client("config", "user.name", name)
-    def _rcs_add(self, path):
+    def _vcs_add(self, path):
         if os.path.isdir(path):
             return
         self._u_invoke_client("add", path)
-    def _rcs_remove(self, path):
+    def _vcs_remove(self, path):
         if not os.path.isdir(self._u_abspath(path)):
             self._u_invoke_client("rm", "-f", path)
-    def _rcs_update(self, path):
-        self._rcs_add(path)
-    def _rcs_get_file_contents(self, path, revision=None, binary=False):
+    def _vcs_update(self, path):
+        self._vcs_add(path)
+    def _vcs_get_file_contents(self, path, revision=None, binary=False):
         if revision == None:
-            return RCS._rcs_get_file_contents(self, path, revision, binary=binary)
+            return vcs.VCS._vcs_get_file_contents(self, path, revision, binary=binary)
         else:
             arg = "%s:%s" % (revision,path)
             status,output,error = self._u_invoke_client("show", arg)
             return output
-    def _rcs_duplicate_repo(self, directory, revision=None):
+    def _vcs_duplicate_repo(self, directory, revision=None):
         if revision==None:
-            RCS._rcs_duplicate_repo(self, directory, revision)
+            vcs.VCS._vcs_duplicate_repo(self, directory, revision)
         else:
             #self._u_invoke_client("archive", revision, directory) # makes tarball
             self._u_invoke_client("clone", "--no-checkout",".",directory)
             self._u_invoke_client("checkout", revision, directory=directory)
-    def _rcs_commit(self, commitfile, allow_empty=False):
+    def _vcs_commit(self, commitfile, allow_empty=False):
         args = ['commit', '--all', '--file', commitfile]
         if allow_empty == True:
             args.append("--allow-empty")
@@ -104,17 +116,33 @@ class Git(RCS):
             strings = ["nothing to commit",
                        "nothing added to commit"]
             if self._u_any_in_string(strings, output) == True:
-                raise rcs.EmptyCommit()
+                raise vcs.EmptyCommit()
         revision = None
         revline = re.compile("(.*) (.*)[:\]] (.*)")
         match = revline.search(output)
         assert match != None, output+error
         assert len(match.groups()) == 3
         revision = match.groups()[1]
-        return revision
+        full_revision = self._vcs_revision_id(-1)
+        assert full_revision.startswith(revision), \
+            "Mismatched revisions:\n%s\n%s" % (revision, full_revision)
+        return full_revision
+    def _vcs_revision_id(self, index):
+        args = ["rev-list", "--first-parent", "--reverse", "HEAD"]
+        kwargs = {"expect":(0,128)}
+        status,output,error = self._u_invoke_client(*args, **kwargs)
+        if status == 128:
+            if error.startswith("fatal: ambiguous argument 'HEAD': unknown "):
+                return None
+            raise vcs.CommandError(args, status, stdout="", stderr=error)
+        commits = output.splitlines()
+        try:
+            return commits[index]
+        except IndexError:
+            return None
 
     
-rcs.make_rcs_testcase_subclasses(Git, sys.modules[__name__])
+vcs.make_vcs_testcase_subclasses(Git, sys.modules[__name__])
 
 unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
 suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/hg.py b/interfaces/web/Bugs-Everywhere-Web/libbe/hg.py
index a20eeb5..f8f8121 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/hg.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/hg.py
@@ -16,81 +16,88 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+"""
+Mercurial (hg) backend.
+"""
+
 import os
 import re
 import sys
 import unittest
 import doctest
 
-import rcs
-from rcs import RCS
+import vcs
+
 
 def new():
     return Hg()
 
-class Hg(RCS):
+class Hg(vcs.VCS):
     name="hg"
     client="hg"
     versioned=True
-    def _rcs_help(self):
+    def _vcs_help(self):
         status,output,error = self._u_invoke_client("--help")
         return output
-    def _rcs_detect(self, path):
+    def _vcs_detect(self, path):
         """Detect whether a directory is revision-controlled using Mercurial"""
         if self._u_search_parent_directories(path, ".hg") != None:
             return True
         return False
-    def _rcs_root(self, path):
+    def _vcs_root(self, path):
         status,output,error = self._u_invoke_client("root", directory=path)
         return output.rstrip('\n')
-    def _rcs_init(self, path):
+    def _vcs_init(self, path):
         self._u_invoke_client("init", directory=path)
-    def _rcs_get_user_id(self):
+    def _vcs_get_user_id(self):
         status,output,error = self._u_invoke_client("showconfig","ui.username")
         return output.rstrip('\n')
-    def _rcs_set_user_id(self, value):
+    def _vcs_set_user_id(self, value):
         """
         Supported by the Config Extension, but that is not part of
         standard Mercurial.
         http://www.selenic.com/mercurial/wiki/index.cgi/ConfigExtension
         """
-        raise rcs.SettingIDnotSupported
-    def _rcs_add(self, path):
+        raise vcs.SettingIDnotSupported
+    def _vcs_add(self, path):
         self._u_invoke_client("add", path)
-    def _rcs_remove(self, path):
+    def _vcs_remove(self, path):
         self._u_invoke_client("rm", "--force", path)
-    def _rcs_update(self, path):
+    def _vcs_update(self, path):
         pass
-    def _rcs_get_file_contents(self, path, revision=None, binary=False):
+    def _vcs_get_file_contents(self, path, revision=None, binary=False):
         if revision == None:
-            return RCS._rcs_get_file_contents(self, path, revision, binary=binary)
+            return vcs.VCS._vcs_get_file_contents(self, path, revision, binary=binary)
         else:
             status,output,error = \
                 self._u_invoke_client("cat","-r",revision,path)
             return output
-    def _rcs_duplicate_repo(self, directory, revision=None):
+    def _vcs_duplicate_repo(self, directory, revision=None):
         if revision == None:
-            return RCS._rcs_duplicate_repo(self, directory, revision)
+            return vcs.VCS._vcs_duplicate_repo(self, directory, revision)
         else:
             self._u_invoke_client("archive", "--rev", revision, directory)
-    def _rcs_commit(self, commitfile, allow_empty=False):
+    def _vcs_commit(self, commitfile, allow_empty=False):
         args = ['commit', '--logfile', commitfile]
         status,output,error = self._u_invoke_client(*args)
         if allow_empty == False:
             strings = ["nothing changed"]
             if self._u_any_in_string(strings, output) == True:
-                raise rcs.EmptyCommit()
-        status,output,error = self._u_invoke_client('identify')
-        revision = None
-        revline = re.compile("(.*) tip")
-        match = revline.search(output)
-        assert match != None, output+error
-        assert len(match.groups()) == 1
-        revision = match.groups()[0]
-        return revision
+                raise vcs.EmptyCommit()
+        return self._vcs_revision_id(-1)
+    def _vcs_revision_id(self, index, style="id"):
+        args = ["identify", "--rev", str(int(index)), "--%s" % style]
+        kwargs = {"expect": (0,255)}
+        status,output,error = self._u_invoke_client(*args, **kwargs)
+        if status == 0:
+            id = output.strip()
+            if id == '000000000000':
+                return None # before initial commit.
+            return id
+        return None
 
     
-rcs.make_rcs_testcase_subclasses(Hg, sys.modules[__name__])
+vcs.make_vcs_testcase_subclasses(Hg, sys.modules[__name__])
 
 unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
 suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/mapfile.py b/interfaces/web/Bugs-Everywhere-Web/libbe/mapfile.py
index b959d76..4d69601 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/mapfile.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/mapfile.py
@@ -14,12 +14,19 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-import yaml
-import os.path
+
+"""
+Provide a means of saving and loading dictionaries of parameters.  The
+saved "mapfiles" should be clear, flat-text files, and allow easy merging of
+independent/conflicting changes.
+"""
+
 import errno
-import utility
+import os.path
+import yaml
 import doctest
 
+
 class IllegalKey(Exception):
     def __init__(self, key):
         Exception.__init__(self, 'Illegal key "%s"' % key)
@@ -95,33 +102,15 @@ def parse(contents):
     >>> dict["e"]
     'f'
     """
-    old_format = False
-    for line in contents.splitlines():
-        if len(line.split("=")) == 2:
-            old_format = True
-            break
-    if old_format: # translate to YAML.  Hack to deal with old BE bugs.
-        newlines = []
-        for line in contents.splitlines():
-            line = line.rstrip('\n')
-            if len(line) == 0:
-                continue
-            fields = line.split("=")
-            if len(fields) == 2:
-                key,value = fields
-                newlines.append('%s: "%s"' % (key, value.replace('"','\\"')))
-            else:
-                newlines.append(line)
-        contents = '\n'.join(newlines)
     return yaml.load(contents) or {}
 
-def map_save(rcs, path, map, allow_no_rcs=False):
+def map_save(vcs, path, map, allow_no_vcs=False):
     """Save the map as a mapfile to the specified path"""
     contents = generate(map)
-    rcs.set_file_contents(path, contents, allow_no_rcs)
+    vcs.set_file_contents(path, contents, allow_no_vcs)
 
-def map_load(rcs, path, allow_no_rcs=False):
-    contents = rcs.get_file_contents(path, allow_no_rcs=allow_no_rcs)
+def map_load(vcs, path, allow_no_vcs=False):
+    contents = vcs.get_file_contents(path, allow_no_vcs=allow_no_vcs)
     return parse(contents)
 
 suite = doctest.DocTestSuite()
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/plugin.py b/interfaces/web/Bugs-Everywhere-Web/libbe/plugin.py
index 0545fd7..d593d69 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/plugin.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/plugin.py
@@ -15,6 +15,12 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Allow simple listing and loading of the various becommands and libbe
+submodules (i.e. "plugins").
+"""
+
 import os
 import os.path
 import sys
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/properties.py b/interfaces/web/Bugs-Everywhere-Web/libbe/properties.py
index 144220b..09dd20e 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/properties.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/properties.py
@@ -160,10 +160,10 @@ def _get_cached_mutable_property(self, cacher_name, property_name, default=None)
     if (cacher_name, property_name) not in self._mutable_property_cache_copy:
         return default
     return self._mutable_property_cache_copy[(cacher_name, property_name)]
-def _cmp_cached_mutable_property(self, cacher_name, property_name, value):
+def _cmp_cached_mutable_property(self, cacher_name, property_name, value, default=None):
     _init_mutable_property_cache(self)
     if (cacher_name, property_name) not in self._mutable_property_cache_hash:
-        return 1 # any value > non-existant old hash
+        _set_cached_mutable_property(self, cacher_name, property_name, default)
     old_hash = self._mutable_property_cache_hash[(cacher_name, property_name)]
     return cmp(_hash_mutable_value(value), old_hash)
 
@@ -327,7 +327,7 @@ def primed_property(primer, initVal=None):
         return funcs
     return decorator
 
-def change_hook_property(hook, mutable=False):
+def change_hook_property(hook, mutable=False, default=None):
     """
     Call the function hook(instance, old_value, new_value) whenever a
     value different from the current value is set (instance is a a
@@ -359,9 +359,9 @@ def change_hook_property(hook, mutable=False):
                 value = new_value # compare new value with cached
             else:
                 value = fget(self) # compare current value with cached
-            if _cmp_cached_mutable_property(self, "change hook property", name, value) != 0:
+            if _cmp_cached_mutable_property(self, "change hook property", name, value, default) != 0:
                 # there has been a change, cache new value
-                old_value = _get_cached_mutable_property(self, "change hook property", name)
+                old_value = _get_cached_mutable_property(self, "change hook property", name, default)
                 _set_cached_mutable_property(self, "change hook property", name, value)
                 if from_fset == True: # return previously cached value
                     value = old_value
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/rcs.py b/interfaces/web/Bugs-Everywhere-Web/libbe/rcs.py
index 294b8e0..e69de29 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/rcs.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/rcs.py
@@ -1,876 +0,0 @@
-# Copyright (C) 2005-2009 Aaron Bentley and Panometrics, Inc.
-#                         Alexander Belchenko <bialix@ukr.net>
-#                         Ben Finney <ben+python@benfinney.id.au>
-#                         Chris Ball <cjb@laptop.org>
-#                         W. Trevor King <wking@drexel.edu>
-#
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2 of the License, or
-# (at your option) any later version.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License along
-# with this program; if not, write to the Free Software Foundation, Inc.,
-# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-
-from subprocess import Popen, PIPE
-import codecs
-import os
-import os.path
-import re
-from socket import gethostname
-import shutil
-import sys
-import tempfile
-import unittest
-import doctest
-
-from utility import Dir, search_parent_directories
-
-
-def _get_matching_rcs(matchfn):
-    """Return the first module for which matchfn(RCS_instance) is true"""
-    import arch
-    import bzr
-    import darcs
-    import git
-    import hg
-    for module in [arch, bzr, darcs, git, hg]:
-        rcs = module.new()
-        if matchfn(rcs) == True:
-            return rcs
-        del(rcs)
-    return RCS()
-    
-def rcs_by_name(rcs_name):
-    """Return the module for the RCS with the given name"""
-    return _get_matching_rcs(lambda rcs: rcs.name == rcs_name)
-
-def detect_rcs(dir):
-    """Return an RCS instance for the rcs being used in this directory"""
-    return _get_matching_rcs(lambda rcs: rcs.detect(dir))
-
-def installed_rcs():
-    """Return an instance of an installed RCS"""
-    return _get_matching_rcs(lambda rcs: rcs.installed())
-
-
-class CommandError(Exception):
-    def __init__(self, command, status, err_str):
-        strerror = ["Command failed (%d):\n  %s\n" % (status, err_str),
-                    "while executing\n  %s" % command]
-        Exception.__init__(self, "\n".join(strerror))
-        self.command = command
-        self.status = status
-        self.err_str = err_str
-
-class SettingIDnotSupported(NotImplementedError):
-    pass
-
-class RCSnotRooted(Exception):
-    def __init__(self):
-        msg = "RCS not rooted"
-        Exception.__init__(self, msg)
-
-class PathNotInRoot(Exception):
-    def __init__(self, path, root):
-        msg = "Path '%s' not in root '%s'" % (path, root)
-        Exception.__init__(self, msg)
-        self.path = path
-        self.root = root
-
-class NoSuchFile(Exception):
-    def __init__(self, pathname, root="."):
-        path = os.path.abspath(os.path.join(root, pathname))
-        Exception.__init__(self, "No such file: %s" % path)
-
-class EmptyCommit(Exception):
-    def __init__(self):
-        Exception.__init__(self, "No changes to commit")
-
-
-def new():
-    return RCS()
-
-class RCS(object):
-    """
-    This class implements a 'no-rcs' interface.
-
-    Support for other RCSs can be added by subclassing this class, and
-    overriding methods _rcs_*() with code appropriate for your RCS.
-    
-    The methods _u_*() are utility methods available to the _rcs_*()
-    methods.
-    """
-    name = "None"
-    client = "" # command-line tool for _u_invoke_client
-    versioned = False
-    def __init__(self, paranoid=False, encoding=sys.getdefaultencoding()):
-        self.paranoid = paranoid
-        self.verboseInvoke = False
-        self.rootdir = None
-        self._duplicateBasedir = None
-        self._duplicateDirname = None
-        self.encoding = encoding
-    def __del__(self):
-        self.cleanup()
-
-    def _rcs_help(self):
-        """
-        Return the command help string.
-        (Allows a simple test to see if the client is installed.)
-        """
-        pass
-    def _rcs_detect(self, path=None):
-        """
-        Detect whether a directory is revision controlled with this RCS.
-        """
-        return True
-    def _rcs_root(self, path):
-        """
-        Get the RCS root.  This is the default working directory for
-        future invocations.  You would normally set this to the root
-        directory for your RCS.
-        """
-        if os.path.isdir(path)==False:
-            path = os.path.dirname(path)
-            if path == "":
-                path = os.path.abspath(".")
-        return path
-    def _rcs_init(self, path):
-        """
-        Begin versioning the tree based at path.
-        """
-        pass
-    def _rcs_cleanup(self):
-        """
-        Remove any cruft that _rcs_init() created outside of the
-        versioned tree.
-        """
-        pass
-    def _rcs_get_user_id(self):
-        """
-        Get the RCS's suggested user id (e.g. "John Doe <jdoe@example.com>").
-        If the RCS has not been configured with a username, return None.
-        """
-        return None
-    def _rcs_set_user_id(self, value):
-        """
-        Set the RCS's suggested user id (e.g "John Doe <jdoe@example.com>").
-        This is run if the RCS has not been configured with a usename, so
-        that commits will have a reasonable FROM value.
-        """
-        raise SettingIDnotSupported
-    def _rcs_add(self, path):
-        """
-        Add the already created file at path to version control.
-        """
-        pass
-    def _rcs_remove(self, path):
-        """
-        Remove the file at path from version control.  Optionally
-        remove the file from the filesystem as well.
-        """
-        pass
-    def _rcs_update(self, path):
-        """
-        Notify the versioning system of changes to the versioned file
-        at path.
-        """
-        pass
-    def _rcs_get_file_contents(self, path, revision=None, binary=False):
-        """
-        Get the file contents as they were in a given revision.
-        Revision==None specifies the current revision.
-        """
-        assert revision == None, \
-            "The %s RCS does not support revision specifiers" % self.name
-        if binary == False:
-            f = codecs.open(os.path.join(self.rootdir, path), "r", self.encoding)
-        else:
-            f = open(os.path.join(self.rootdir, path), "rb")
-        contents = f.read()
-        f.close()
-        return contents
-    def _rcs_duplicate_repo(self, directory, revision=None):
-        """
-        Get the repository as it was in a given revision.
-        revision==None specifies the current revision.
-        dir specifies a directory to create the duplicate in.
-        """
-        shutil.copytree(self.rootdir, directory, True)
-    def _rcs_commit(self, commitfile, allow_empty=False):
-        """
-        Commit the current working directory, using the contents of
-        commitfile as the comment.  Return the name of the old
-        revision (or None if commits are not supported).
-        
-        If allow_empty == False, raise EmptyCommit if there are no
-        changes to commit.
-        """
-        return None
-    def installed(self):
-        try:
-            self._rcs_help()
-            return True
-        except OSError, e:
-            if e.errno == errno.ENOENT:
-                return False
-        except CommandError:
-            return False
-    def detect(self, path="."):
-        """
-        Detect whether a directory is revision controlled with this RCS.
-        """
-        return self._rcs_detect(path)
-    def root(self, path):
-        """
-        Set the root directory to the path's RCS root.  This is the
-        default working directory for future invocations.
-        """
-        self.rootdir = self._rcs_root(path)
-    def init(self, path):
-        """
-        Begin versioning the tree based at path.
-        Also roots the rcs at path.
-        """
-        if os.path.isdir(path)==False:
-            path = os.path.dirname(path)
-        self._rcs_init(path)
-        self.root(path)
-    def cleanup(self):
-        self._rcs_cleanup()
-    def get_user_id(self):
-        """
-        Get the RCS's suggested user id (e.g. "John Doe <jdoe@example.com>").
-        If the RCS has not been configured with a username, return the user's
-        id.  You can override the automatic lookup procedure by setting the
-        RCS.user_id attribute to a string of your choice.
-        """
-        if hasattr(self, "user_id"):
-            if self.user_id != None:
-                return self.user_id
-        id = self._rcs_get_user_id()
-        if id == None:
-            name = self._u_get_fallback_username()
-            email = self._u_get_fallback_email()
-            id = self._u_create_id(name, email)
-            print >> sys.stderr, "Guessing id '%s'" % id
-            try:
-                self.set_user_id(id)
-            except SettingIDnotSupported:
-                pass
-        return id
-    def set_user_id(self, value):
-        """
-        Set the RCS's suggested user id (e.g "John Doe <jdoe@example.com>").
-        This is run if the RCS has not been configured with a usename, so
-        that commits will have a reasonable FROM value.
-        """
-        self._rcs_set_user_id(value)
-    def add(self, path):
-        """
-        Add the already created file at path to version control.
-        """
-        self._rcs_add(self._u_rel_path(path))
-    def remove(self, path):
-        """
-        Remove a file from both version control and the filesystem.
-        """
-        self._rcs_remove(self._u_rel_path(path))
-        if os.path.exists(path):
-            os.remove(path)
-    def recursive_remove(self, dirname):
-        """
-        Remove a file/directory and all its decendents from both
-        version control and the filesystem.
-        """
-        if not os.path.exists(dirname):
-            raise NoSuchFile(dirname)
-        for dirpath,dirnames,filenames in os.walk(dirname, topdown=False):
-            filenames.extend(dirnames)
-            for path in filenames:
-                fullpath = os.path.join(dirpath, path)
-                if os.path.exists(fullpath) == False:
-                    continue
-                self._rcs_remove(self._u_rel_path(fullpath))
-        if os.path.exists(dirname):
-            shutil.rmtree(dirname)
-    def update(self, path):
-        """
-        Notify the versioning system of changes to the versioned file
-        at path.
-        """
-        self._rcs_update(self._u_rel_path(path))
-    def get_file_contents(self, path, revision=None, allow_no_rcs=False, binary=False):
-        """
-        Get the file as it was in a given revision.
-        Revision==None specifies the current revision.
-        """
-        if not os.path.exists(path):
-            raise NoSuchFile(path)
-        if self._use_rcs(path, allow_no_rcs):
-            relpath = self._u_rel_path(path)
-            contents = self._rcs_get_file_contents(relpath,revision,binary=binary)
-        else:
-            f = codecs.open(path, "r", self.encoding)
-            contents = f.read()
-            f.close()
-        return contents
-    def set_file_contents(self, path, contents, allow_no_rcs=False, binary=False):
-        """
-        Set the file contents under version control.
-        """
-        add = not os.path.exists(path)
-        if binary == False:
-            f = codecs.open(path, "w", self.encoding)
-        else:
-            f = open(path, "wb")
-        f.write(contents)
-        f.close()
-        
-        if self._use_rcs(path, allow_no_rcs):
-            if add:
-                self.add(path)
-            else:
-                self.update(path)
-    def mkdir(self, path, allow_no_rcs=False, check_parents=True):
-        """
-        Create (if neccessary) a directory at path under version
-        control.
-        """
-        if check_parents == True:
-            parent = os.path.dirname(path)
-            if not os.path.exists(parent): # recurse through parents
-                self.mkdir(parent, allow_no_rcs, check_parents)
-        if not os.path.exists(path):
-            os.mkdir(path)
-            if self._use_rcs(path, allow_no_rcs):
-                self.add(path)
-        else:
-            assert os.path.isdir(path)
-            if self._use_rcs(path, allow_no_rcs):
-                #self.update(path)# Don't update directories.  Changing files
-                pass              # underneath them should be sufficient.
-                
-    def duplicate_repo(self, revision=None):
-        """
-        Get the repository as it was in a given revision.
-        revision==None specifies the current revision.
-        Return the path to the arbitrary directory at the base of the new repo.
-        """
-        # Dirname in Baseir to protect against simlink attacks.
-        if self._duplicateBasedir == None:
-            self._duplicateBasedir = tempfile.mkdtemp(prefix='BErcs')
-            self._duplicateDirname = \
-                os.path.join(self._duplicateBasedir, "duplicate")
-            self._rcs_duplicate_repo(directory=self._duplicateDirname,
-                                     revision=revision)
-        return self._duplicateDirname
-    def remove_duplicate_repo(self):
-        """
-        Clean up a duplicate repo created with duplicate_repo().
-        """
-        if self._duplicateBasedir != None:
-            shutil.rmtree(self._duplicateBasedir)
-            self._duplicateBasedir = None
-            self._duplicateDirname = None
-    def commit(self, summary, body=None, allow_empty=False):
-        """
-        Commit the current working directory, with a commit message
-        string summary and body.  Return the name of the old revision
-        (or None if versioning is not supported).
-        
-        If allow_empty == False (the default), raise EmptyCommit if
-        there are no changes to commit.
-        """
-        summary = summary.strip()+'\n'
-        if body is not None:
-            summary += '\n' + body.strip() + '\n'
-        descriptor, filename = tempfile.mkstemp()
-        revision = None
-        try:
-            temp_file = os.fdopen(descriptor, 'wb')
-            temp_file.write(summary)
-            temp_file.flush()
-            self.precommit()
-            revision = self._rcs_commit(filename, allow_empty=allow_empty)
-            temp_file.close()
-            self.postcommit()
-        finally:
-            os.remove(filename)
-        return revision
-    def precommit(self):
-        """
-        Executed before all attempted commits.
-        """
-        pass
-    def postcommit(self):
-        """
-        Only executed after successful commits.
-        """
-        pass
-    def _u_any_in_string(self, list, string):
-        """
-        Return True if any of the strings in list are in string.
-        Otherwise return False.
-        """
-        for list_string in list:
-            if list_string in string:
-                return True
-        return False
-    def _u_invoke(self, args, stdin=None, expect=(0,), cwd=None):
-        """
-        expect should be a tuple of allowed exit codes.  cwd should be
-        the directory from which the command will be executed.
-        """
-        if cwd == None:
-            cwd = self.rootdir
-        if self.verboseInvoke == True:
-            print >> sys.stderr, "%s$ %s" % (cwd, " ".join(args))
-        try :
-            if sys.platform != "win32":
-                q = Popen(args, stdin=PIPE, stdout=PIPE, stderr=PIPE, cwd=cwd)
-            else:
-                # win32 don't have os.execvp() so have to run command in a shell
-                q = Popen(args, stdin=PIPE, stdout=PIPE, stderr=PIPE, 
-                          shell=True, cwd=cwd)
-        except OSError, e :
-            raise CommandError(args, e.args[0], e)
-        output, error = q.communicate(input=stdin)
-        status = q.wait()
-        if self.verboseInvoke == True:
-            print >> sys.stderr, "%d\n%s%s" % (status, output, error)
-        if status not in expect:
-            raise CommandError(args, status, error)
-        return status, output, error
-    def _u_invoke_client(self, *args, **kwargs):
-        directory = kwargs.get('directory',None)
-        expect = kwargs.get('expect', (0,))
-        stdin = kwargs.get('stdin', None)
-        cl_args = [self.client]
-        cl_args.extend(args)
-        return self._u_invoke(cl_args, stdin=stdin,expect=expect,cwd=directory)
-    def _u_search_parent_directories(self, path, filename):
-        """
-        Find the file (or directory) named filename in path or in any
-        of path's parents.
-        
-        e.g.
-          search_parent_directories("/a/b/c", ".be")
-        will return the path to the first existing file from
-          /a/b/c/.be
-          /a/b/.be
-          /a/.be
-          /.be
-        or None if none of those files exist.
-        """
-        return search_parent_directories(path, filename)
-    def _use_rcs(self, path, allow_no_rcs):
-        """
-        Try and decide if _rcs_add/update/mkdir/etc calls will
-        succeed.  Returns True is we think the rcs_call would
-        succeeed, and False otherwise.
-        """
-        use_rcs = True
-        exception = None
-        if self.rootdir != None:
-            if self.path_in_root(path) == False:
-                use_rcs = False
-                exception = PathNotInRoot(path, self.rootdir)
-        else:
-            use_rcs = False
-            exception = RCSnotRooted
-        if use_rcs == False and allow_no_rcs==False:
-            raise exception
-        return use_rcs
-    def path_in_root(self, path, root=None):
-        """
-        Return the relative path to path from root.
-        >>> rcs = new()
-        >>> rcs.path_in_root("/a.b/c/.be", "/a.b/c")
-        True
-        >>> rcs.path_in_root("/a.b/.be", "/a.b/c")
-        False
-        """
-        if root == None:
-            if self.rootdir == None:
-                raise RCSnotRooted
-            root = self.rootdir
-        path = os.path.abspath(path)
-        absRoot = os.path.abspath(root)
-        absRootSlashedDir = os.path.join(absRoot,"")
-        if not path.startswith(absRootSlashedDir):
-            return False
-        return True
-    def _u_rel_path(self, path, root=None):
-        """
-        Return the relative path to path from root.
-        >>> rcs = new()
-        >>> rcs._u_rel_path("/a.b/c/.be", "/a.b/c")
-        '.be'
-        """
-        if root == None:
-            if self.rootdir == None:
-                raise RCSnotRooted
-            root = self.rootdir
-        path = os.path.abspath(path)
-        absRoot = os.path.abspath(root)
-        absRootSlashedDir = os.path.join(absRoot,"")
-        if not path.startswith(absRootSlashedDir):
-            raise PathNotInRoot(path, absRootSlashedDir)
-        assert path != absRootSlashedDir, \
-            "file %s == root directory %s" % (path, absRootSlashedDir)
-        relpath = path[len(absRootSlashedDir):]
-        return relpath
-    def _u_abspath(self, path, root=None):
-        """
-        Return the absolute path from a path realtive to root.
-        >>> rcs = new()
-        >>> rcs._u_abspath(".be", "/a.b/c")
-        '/a.b/c/.be'
-        """
-        if root == None:
-            assert self.rootdir != None, "RCS not rooted"
-            root = self.rootdir
-        return os.path.abspath(os.path.join(root, path))
-    def _u_create_id(self, name, email=None):
-        """
-        >>> rcs = new()
-        >>> rcs._u_create_id("John Doe", "jdoe@example.com")
-        'John Doe <jdoe@example.com>'
-        >>> rcs._u_create_id("John Doe")
-        'John Doe'
-        """
-        assert len(name) > 0
-        if email == None or len(email) == 0:
-            return name
-        else:
-            return "%s <%s>" % (name, email)
-    def _u_parse_id(self, value):
-        """
-        >>> rcs = new()
-        >>> rcs._u_parse_id("John Doe <jdoe@example.com>")
-        ('John Doe', 'jdoe@example.com')
-        >>> rcs._u_parse_id("John Doe")
-        ('John Doe', None)
-        >>> try:
-        ...     rcs._u_parse_id("John Doe <jdoe@example.com><what?>")
-        ... except AssertionError:
-        ...     print "Invalid match"
-        Invalid match
-        """
-        emailexp = re.compile("(.*) <([^>]*)>(.*)")
-        match = emailexp.search(value)
-        if match == None:
-            email = None
-            name = value
-        else:
-            assert len(match.groups()) == 3
-            assert match.groups()[2] == "", match.groups()
-            email = match.groups()[1]
-            name = match.groups()[0]
-        assert name != None
-        assert len(name) > 0
-        return (name, email)
-    def _u_get_fallback_username(self):
-        name = None
-        for envariable in ["LOGNAME", "USERNAME"]:
-            if os.environ.has_key(envariable):
-                name = os.environ[envariable]
-                break
-        assert name != None
-        return name
-    def _u_get_fallback_email(self):
-        hostname = gethostname()
-        name = self._u_get_fallback_username()
-        return "%s@%s" % (name, hostname)
-    def _u_parse_commitfile(self, commitfile):
-        """
-        Split the commitfile created in self.commit() back into
-        summary and header lines.
-        """
-        f = codecs.open(commitfile, "r", self.encoding)
-        summary = f.readline()
-        body = f.read()
-        body.lstrip('\n')
-        if len(body) == 0:
-            body = None
-        f.close()
-        return (summary, body)
-        
-
-def setup_rcs_test_fixtures(testcase):
-    """Set up test fixtures for RCS test case."""
-    testcase.rcs = testcase.Class()
-    testcase.dir = Dir()
-    testcase.dirname = testcase.dir.path
-
-    rcs_not_supporting_uninitialized_user_id = []
-    rcs_not_supporting_set_user_id = ["None", "hg"]
-    testcase.rcs_supports_uninitialized_user_id = (
-        testcase.rcs.name not in rcs_not_supporting_uninitialized_user_id)
-    testcase.rcs_supports_set_user_id = (
-        testcase.rcs.name not in rcs_not_supporting_set_user_id)
-
-    if not testcase.rcs.installed():
-        testcase.fail(
-            "%(name)s RCS not found" % vars(testcase.Class))
-
-    if testcase.Class.name != "None":
-        testcase.failIf(
-            testcase.rcs.detect(testcase.dirname),
-            "Detected %(name)s RCS before initialising"
-                % vars(testcase.Class))
-
-    testcase.rcs.init(testcase.dirname)
-
-
-class RCSTestCase(unittest.TestCase):
-    """Test cases for base RCS class."""
-
-    Class = RCS
-
-    def __init__(self, *args, **kwargs):
-        super(RCSTestCase, self).__init__(*args, **kwargs)
-        self.dirname = None
-
-    def setUp(self):
-        super(RCSTestCase, self).setUp()
-        setup_rcs_test_fixtures(self)
-
-    def tearDown(self):
-        del(self.rcs)
-        super(RCSTestCase, self).tearDown()
-
-    def full_path(self, rel_path):
-        return os.path.join(self.dirname, rel_path)
-
-
-class RCS_init_TestCase(RCSTestCase):
-    """Test cases for RCS.init method."""
-
-    def test_detect_should_succeed_after_init(self):
-        """Should detect RCS in directory after initialization."""
-        self.failUnless(
-            self.rcs.detect(self.dirname),
-            "Did not detect %(name)s RCS after initialising"
-                % vars(self.Class))
-
-    def test_rcs_rootdir_in_specified_root_path(self):
-        """RCS root directory should be in specified root path."""
-        rp = os.path.realpath(self.rcs.rootdir)
-        dp = os.path.realpath(self.dirname)
-        rcs_name = self.Class.name
-        self.failUnless(
-            dp == rp or rp == None,
-            "%(rcs_name)s RCS root in wrong dir (%(dp)s %(rp)s)" % vars())
-
-
-class RCS_get_user_id_TestCase(RCSTestCase):
-    """Test cases for RCS.get_user_id method."""
-
-    def test_gets_existing_user_id(self):
-        """Should get the existing user ID."""
-        if not self.rcs_supports_uninitialized_user_id:
-            return
-
-        user_id = self.rcs.get_user_id()
-        self.failUnless(
-            user_id is not None,
-            "unable to get a user id")
-
-
-class RCS_set_user_id_TestCase(RCSTestCase):
-    """Test cases for RCS.set_user_id method."""
-
-    def setUp(self):
-        super(RCS_set_user_id_TestCase, self).setUp()
-
-        if self.rcs_supports_uninitialized_user_id:
-            self.prev_user_id = self.rcs.get_user_id()
-        else:
-            self.prev_user_id = "Uninitialized identity <bogus@example.org>"
-
-        if self.rcs_supports_set_user_id:
-            self.test_new_user_id = "John Doe <jdoe@example.com>"
-            self.rcs.set_user_id(self.test_new_user_id)
-
-    def tearDown(self):
-        if self.rcs_supports_set_user_id:
-            self.rcs.set_user_id(self.prev_user_id)
-        super(RCS_set_user_id_TestCase, self).tearDown()
-
-    def test_raises_error_in_unsupported_vcs(self):
-        """Should raise an error in a VCS that doesn't support it."""
-        if self.rcs_supports_set_user_id:
-            return
-        self.assertRaises(
-            SettingIDnotSupported,
-            self.rcs.set_user_id, "foo")
-
-    def test_updates_user_id_in_supporting_rcs(self):
-        """Should update the user ID in an RCS that supports it."""
-        if not self.rcs_supports_set_user_id:
-            return
-        user_id = self.rcs.get_user_id()
-        self.failUnlessEqual(
-            self.test_new_user_id, user_id,
-            "user id not set correctly (expected %s, got %s)"
-                % (self.test_new_user_id, user_id))
-
-
-def setup_rcs_revision_test_fixtures(testcase):
-    """Set up revision test fixtures for RCS test case."""
-    testcase.test_dirs = ['a', 'a/b', 'c']
-    for path in testcase.test_dirs:
-        testcase.rcs.mkdir(testcase.full_path(path))
-
-    testcase.test_files = ['a/text', 'a/b/text']
-
-    testcase.test_contents = {
-        'rev_1': "Lorem ipsum",
-        'uncommitted': "dolor sit amet",
-        }
-
-
-class RCS_mkdir_TestCase(RCSTestCase):
-    """Test cases for RCS.mkdir method."""
-
-    def setUp(self):
-        super(RCS_mkdir_TestCase, self).setUp()
-        setup_rcs_revision_test_fixtures(self)
-
-    def tearDown(self):
-        for path in reversed(sorted(self.test_dirs)):
-            self.rcs.recursive_remove(self.full_path(path))
-        super(RCS_mkdir_TestCase, self).tearDown()
-
-    def test_mkdir_creates_directory(self):
-        """Should create specified directory in filesystem."""
-        for path in self.test_dirs:
-            full_path = self.full_path(path)
-            self.failUnless(
-                os.path.exists(full_path),
-                "path %(full_path)s does not exist" % vars())
-
-
-class RCS_commit_TestCase(RCSTestCase):
-    """Test cases for RCS.commit method."""
-
-    def setUp(self):
-        super(RCS_commit_TestCase, self).setUp()
-        setup_rcs_revision_test_fixtures(self)
-
-    def tearDown(self):
-        for path in reversed(sorted(self.test_dirs)):
-            self.rcs.recursive_remove(self.full_path(path))
-        super(RCS_commit_TestCase, self).tearDown()
-
-    def test_file_contents_as_specified(self):
-        """Should set file contents as specified."""
-        test_contents = self.test_contents['rev_1']
-        for path in self.test_files:
-            full_path = self.full_path(path)
-            self.rcs.set_file_contents(full_path, test_contents)
-            current_contents = self.rcs.get_file_contents(full_path)
-            self.failUnlessEqual(test_contents, current_contents)
-
-    def test_file_contents_as_committed(self):
-        """Should have file contents as specified after commit."""
-        test_contents = self.test_contents['rev_1']
-        for path in self.test_files:
-            full_path = self.full_path(path)
-            self.rcs.set_file_contents(full_path, test_contents)
-            revision = self.rcs.commit("Initial file contents.")
-            current_contents = self.rcs.get_file_contents(full_path)
-            self.failUnlessEqual(test_contents, current_contents)
-
-    def test_file_contents_as_set_when_uncommitted(self):
-        """Should set file contents as specified after commit."""
-        if not self.rcs.versioned:
-            return
-        for path in self.test_files:
-            full_path = self.full_path(path)
-            self.rcs.set_file_contents(
-                full_path, self.test_contents['rev_1'])
-            revision = self.rcs.commit("Initial file contents.")
-            self.rcs.set_file_contents(
-                full_path, self.test_contents['uncommitted'])
-            current_contents = self.rcs.get_file_contents(full_path)
-            self.failUnlessEqual(
-                self.test_contents['uncommitted'], current_contents)
-
-    def test_revision_file_contents_as_committed(self):
-        """Should get file contents as committed to specified revision."""
-        if not self.rcs.versioned:
-            return
-        for path in self.test_files:
-            full_path = self.full_path(path)
-            self.rcs.set_file_contents(
-                full_path, self.test_contents['rev_1'])
-            revision = self.rcs.commit("Initial file contents.")
-            self.rcs.set_file_contents(
-                full_path, self.test_contents['uncommitted'])
-            committed_contents = self.rcs.get_file_contents(
-                full_path, revision)
-            self.failUnlessEqual(
-                self.test_contents['rev_1'], committed_contents)
-
-
-class RCS_duplicate_repo_TestCase(RCSTestCase):
-    """Test cases for RCS.duplicate_repo method."""
-
-    def setUp(self):
-        super(RCS_duplicate_repo_TestCase, self).setUp()
-        setup_rcs_revision_test_fixtures(self)
-
-    def tearDown(self):
-        self.rcs.remove_duplicate_repo()
-        for path in reversed(sorted(self.test_dirs)):
-            self.rcs.recursive_remove(self.full_path(path))
-        super(RCS_duplicate_repo_TestCase, self).tearDown()
-
-    def test_revision_file_contents_as_committed(self):
-        """Should match file contents as committed to specified revision."""
-        if not self.rcs.versioned:
-            return
-        for path in self.test_files:
-            full_path = self.full_path(path)
-            self.rcs.set_file_contents(
-                full_path, self.test_contents['rev_1'])
-            revision = self.rcs.commit("Commit current status")
-            self.rcs.set_file_contents(
-                full_path, self.test_contents['uncommitted'])
-            dup_repo_path = self.rcs.duplicate_repo(revision)
-            dup_file_path = os.path.join(dup_repo_path, path)
-            dup_file_contents = file(dup_file_path, 'rb').read()
-            self.failUnlessEqual(
-                self.test_contents['rev_1'], dup_file_contents)
-            self.rcs.remove_duplicate_repo()
-
-
-def make_rcs_testcase_subclasses(rcs_class, namespace):
-    """Make RCSTestCase subclasses for rcs_class in the namespace."""
-    rcs_testcase_classes = [
-        c for c in (
-            ob for ob in globals().values() if isinstance(ob, type))
-        if issubclass(c, RCSTestCase)]
-
-    for base_class in rcs_testcase_classes:
-        testcase_class_name = rcs_class.__name__ + base_class.__name__
-        testcase_class_bases = (base_class,)
-        testcase_class_dict = dict(base_class.__dict__)
-        testcase_class_dict['Class'] = rcs_class
-        testcase_class = type(
-            testcase_class_name, testcase_class_bases, testcase_class_dict)
-        setattr(namespace, testcase_class_name, testcase_class)
-
-
-unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
-suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/settings_object.py b/interfaces/web/Bugs-Everywhere-Web/libbe/settings_object.py
index dde247f..ceea9d5 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/settings_object.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/settings_object.py
@@ -148,7 +148,8 @@ def versioned_property(name, doc,
             checked = checked_property(allowed=allowed)
             fulldoc += "\n\nThe allowed values for this property are: %s." \
                        % (', '.join(allowed))
-        hooked      = change_hook_property(hook=change_hook, mutable=mutable)
+        hooked      = change_hook_property(hook=change_hook, mutable=mutable,
+                                           default=EMPTY)
         primed      = primed_property(primer=primer, initVal=UNPRIMED)
         settings    = settings_property(name=name, null=UNPRIMED)
         docp        = doc_property(doc=fulldoc)
@@ -385,30 +386,24 @@ class SavedSettingsObjectTests(unittest.TestCase):
         self.failUnless(SAVES == [], SAVES)
         self.failUnless(t._settings_loaded == True, t._settings_loaded)
         self.failUnless(t.list_type == None, t.list_type)
-        self.failUnless(SAVES == [
-                "'None' -> '<class 'libbe.settings_object.EMPTY'>'"
-                ], SAVES)
+        self.failUnless(SAVES == [], SAVES)
         self.failUnless(t.settings["List-type"]==EMPTY,t.settings["List-type"])
         t.list_type = []
         self.failUnless(t.settings["List-type"] == [], t.settings["List-type"])
         self.failUnless(SAVES == [
-                "'None' -> '<class 'libbe.settings_object.EMPTY'>'",
                 "'<class 'libbe.settings_object.EMPTY'>' -> '[]'"
                 ], SAVES)
         t.list_type.append(5)
         self.failUnless(SAVES == [
-                "'None' -> '<class 'libbe.settings_object.EMPTY'>'",
                 "'<class 'libbe.settings_object.EMPTY'>' -> '[]'",
                 ], SAVES)
         self.failUnless(t.settings["List-type"] == [5],t.settings["List-type"])
         self.failUnless(SAVES == [ # the append(5) has not yet been saved
-                "'None' -> '<class 'libbe.settings_object.EMPTY'>'",
                 "'<class 'libbe.settings_object.EMPTY'>' -> '[]'",
                 ], SAVES)
         self.failUnless(t.list_type == [5], t.list_type) # <-get triggers saved
 
         self.failUnless(SAVES == [ # now the append(5) has been saved.
-                "'None' -> '<class 'libbe.settings_object.EMPTY'>'",
                 "'<class 'libbe.settings_object.EMPTY'>' -> '[]'",
                 "'[]' -> '[5]'"
                 ], SAVES)
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/tree.py b/interfaces/web/Bugs-Everywhere-Web/libbe/tree.py
index 45ae085..06d09e5 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/tree.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/tree.py
@@ -15,6 +15,10 @@
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+"""
+Define a traversable tree structure.
+"""
+
 import doctest
 
 class Tree(list):
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/upgrade.py b/interfaces/web/Bugs-Everywhere-Web/libbe/upgrade.py
new file mode 100644
index 0000000..4123c72
--- /dev/null
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/upgrade.py
@@ -0,0 +1,187 @@
+# Copyright (C) 2009 W. Trevor King <wking@drexel.edu>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Handle conversion between the various on-disk images.
+"""
+
+import os, os.path
+import sys
+import doctest
+
+import encoding
+import mapfile
+import vcs
+
+# a list of all past versions
+BUGDIR_DISK_VERSIONS = ["Bugs Everywhere Tree 1 0",
+                        "Bugs Everywhere Directory v1.1",
+                        "Bugs Everywhere Directory v1.2"]
+
+# the current version
+BUGDIR_DISK_VERSION = BUGDIR_DISK_VERSIONS[-1]
+
+class Upgrader (object):
+    "Class for converting "
+    initial_version = None
+    final_version = None
+    def __init__(self, root):
+        self.root = root
+        # use the "None" VCS to ensure proper encoding/decoding and
+        # simplify path construction.
+        self.vcs = vcs.vcs_by_name("None")
+        self.vcs.root(self.root)
+        self.vcs.encoding = encoding.get_encoding()
+
+    def get_path(self, *args):
+        """
+        Return a path relative to .root.
+        """
+        dir = os.path.join(self.root, ".be")
+        if len(args) == 0:
+            return dir
+        assert args[0] in ["version", "settings", "bugs"], str(args)
+        return os.path.join(dir, *args)
+
+    def check_initial_version(self):
+        path = self.get_path("version")
+        version = self.vcs.get_file_contents(path).rstrip("\n")
+        assert version == self.initial_version, version
+
+    def set_version(self):
+        path = self.get_path("version")
+        self.vcs.set_file_contents(path, self.final_version+"\n")
+
+    def upgrade(self):
+        print >> sys.stderr, "upgrading bugdir from '%s' to '%s'" \
+            % (self.initial_version, self.final_version)
+        self.check_initial_version()
+        self.set_version()
+        self._upgrade()
+
+    def _upgrade(self):
+        raise NotImplementedError
+
+
+class Upgrade_1_0_to_1_1 (Upgrader):
+    initial_version = "Bugs Everywhere Tree 1 0"
+    final_version = "Bugs Everywhere Directory v1.1"
+    def _upgrade_mapfile(self, path):
+        contents = self.vcs.get_file_contents(path)
+        old_format = False
+        for line in contents.splitlines():
+            if len(line.split("=")) == 2:
+                old_format = True
+                break
+        if old_format == True:
+            # translate to YAML.
+            newlines = []
+            for line in contents.splitlines():
+                line = line.rstrip('\n')
+                if len(line) == 0:
+                    continue
+                fields = line.split("=")
+                if len(fields) == 2:
+                    key,value = fields
+                    newlines.append('%s: "%s"' % (key, value.replace('"','\\"')))
+                else:
+                    newlines.append(line)
+            contents = '\n'.join(newlines)
+            # load the YAML and save
+            map = mapfile.parse(contents)
+            mapfile.map_save(self.vcs, path, map)
+
+    def _upgrade(self):
+        """
+        Comment value field "From" -> "Author".
+        Homegrown mapfile -> YAML.
+        """
+        path = self.get_path("settings")
+        self._upgrade_mapfile(path)
+        for bug_uuid in os.listdir(self.get_path("bugs")):
+            path = self.get_path("bugs", bug_uuid, "values")
+            self._upgrade_mapfile(path)
+            c_path = ["bugs", bug_uuid, "comments"]
+            if not os.path.exists(self.get_path(*c_path)):
+                continue # no comments for this bug
+            for comment_uuid in os.listdir(self.get_path(*c_path)):
+                path_list = c_path + [comment_uuid, "values"]
+                path = self.get_path(*path_list)
+                self._upgrade_mapfile(path)
+                settings = mapfile.map_load(self.vcs, path)
+                if "From" in settings:
+                    settings["Author"] = settings.pop("From")
+                    mapfile.map_save(self.vcs, path, settings)
+
+
+class Upgrade_1_1_to_1_2 (Upgrader):
+    initial_version = "Bugs Everywhere Directory v1.1"
+    final_version = "Bugs Everywhere Directory v1.2"
+    def _upgrade(self):
+        """
+        BugDir settings field "rcs_name" -> "vcs_name".
+        """
+        path = self.get_path("settings")
+        settings = mapfile.map_load(self.vcs, path)
+        if "rcs_name" in settings:
+            settings["vcs_name"] = settings.pop("rcs_name")
+            mapfile.map_save(self.vcs, path, settings)
+
+
+upgraders = [Upgrade_1_0_to_1_1,
+             Upgrade_1_1_to_1_2]
+upgrade_classes = {}
+for upgrader in upgraders:
+    upgrade_classes[(upgrader.initial_version,upgrader.final_version)]=upgrader
+
+def upgrade(path, current_version,
+            target_version=BUGDIR_DISK_VERSION):
+    """
+    Call the appropriate upgrade function to convert current_version
+    to target_version.  If a direct conversion function does not exist,
+    use consecutive conversion functions.
+    """
+    if current_version not in BUGDIR_DISK_VERSIONS:
+        raise NotImplementedError, \
+            "Cannot handle version '%s' yet." % version
+    if target_version not in BUGDIR_DISK_VERSIONS:
+        raise NotImplementedError, \
+            "Cannot handle version '%s' yet." % version
+
+    if (current_version, target_version) in upgrade_classes:
+        # direct conversion
+        upgrade_class = upgrade_classes[(current_version, target_version)]
+        u = upgrade_class(path)
+        u.upgrade()
+    else:
+        # consecutive single-step conversion
+        i = BUGDIR_DISK_VERSIONS.index(current_version)
+        while True:
+            version_a = BUGDIR_DISK_VERSIONS[i]
+            version_b = BUGDIR_DISK_VERSIONS[i+1]
+            try:
+                upgrade_class = upgrade_classes[(version_a, version_b)]
+            except KeyError:
+                raise NotImplementedError, \
+                    "Cannot convert version '%s' to '%s' yet." \
+                    % (version_a, version_b)
+            u = upgrade_class(path)
+            u.upgrade()
+            if version_b == target_version:
+                break
+            i += 1
+
+suite = doctest.DocTestSuite()
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/utility.py b/interfaces/web/Bugs-Everywhere-Web/libbe/utility.py
index 3df06b4..aafbf8d 100644
--- a/interfaces/web/Bugs-Everywhere-Web/libbe/utility.py
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/utility.py
@@ -14,6 +14,11 @@
 # You should have received a copy of the GNU General Public License along
 # with this program; if not, write to the Free Software Foundation, Inc.,
 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Assorted utility functions that don't fit in anywhere else.
+"""
+
 import calendar
 import codecs
 import os
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/vcs.py b/interfaces/web/Bugs-Everywhere-Web/libbe/vcs.py
new file mode 100644
index 0000000..a1d3022
--- /dev/null
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/vcs.py
@@ -0,0 +1,938 @@
+# Copyright (C) 2005-2009 Aaron Bentley and Panometrics, Inc.
+#                         Alexander Belchenko <bialix@ukr.net>
+#                         Ben Finney <ben+python@benfinney.id.au>
+#                         Chris Ball <cjb@laptop.org>
+#                         W. Trevor King <wking@drexel.edu>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Define the base VCS (Version Control System) class, which should be
+subclassed by other Version Control System backends.  The base class
+implements a "do not version" VCS.
+"""
+
+from subprocess import Popen, PIPE
+import codecs
+import os
+import os.path
+import re
+from socket import gethostname
+import shutil
+import sys
+import tempfile
+import unittest
+import doctest
+
+from utility import Dir, search_parent_directories
+
+
+def _get_matching_vcs(matchfn):
+    """Return the first module for which matchfn(VCS_instance) is true"""
+    import arch
+    import bzr
+    import darcs
+    import git
+    import hg
+    for module in [arch, bzr, darcs, git, hg]:
+        vcs = module.new()
+        if matchfn(vcs) == True:
+            return vcs
+        del(vcs)
+    return VCS()
+    
+def vcs_by_name(vcs_name):
+    """Return the module for the VCS with the given name"""
+    return _get_matching_vcs(lambda vcs: vcs.name == vcs_name)
+
+def detect_vcs(dir):
+    """Return an VCS instance for the vcs being used in this directory"""
+    return _get_matching_vcs(lambda vcs: vcs.detect(dir))
+
+def installed_vcs():
+    """Return an instance of an installed VCS"""
+    return _get_matching_vcs(lambda vcs: vcs.installed())
+
+
+class CommandError(Exception):
+    def __init__(self, command, status, stdout, stderr):
+        strerror = ["Command failed (%d):\n  %s\n" % (status, stderr),
+                    "while executing\n  %s" % command]
+        Exception.__init__(self, "\n".join(strerror))
+        self.command = command
+        self.status = status
+        self.stdout = stdout
+        self.stderr = stderr
+
+class SettingIDnotSupported(NotImplementedError):
+    pass
+
+class VCSnotRooted(Exception):
+    def __init__(self):
+        msg = "VCS not rooted"
+        Exception.__init__(self, msg)
+
+class PathNotInRoot(Exception):
+    def __init__(self, path, root):
+        msg = "Path '%s' not in root '%s'" % (path, root)
+        Exception.__init__(self, msg)
+        self.path = path
+        self.root = root
+
+class NoSuchFile(Exception):
+    def __init__(self, pathname, root="."):
+        path = os.path.abspath(os.path.join(root, pathname))
+        Exception.__init__(self, "No such file: %s" % path)
+
+class EmptyCommit(Exception):
+    def __init__(self):
+        Exception.__init__(self, "No changes to commit")
+
+
+def new():
+    return VCS()
+
+class VCS(object):
+    """
+    This class implements a 'no-vcs' interface.
+
+    Support for other VCSs can be added by subclassing this class, and
+    overriding methods _vcs_*() with code appropriate for your VCS.
+    
+    The methods _u_*() are utility methods available to the _vcs_*()
+    methods.
+    """
+    name = "None"
+    client = "" # command-line tool for _u_invoke_client
+    versioned = False
+    def __init__(self, paranoid=False, encoding=sys.getdefaultencoding()):
+        self.paranoid = paranoid
+        self.verboseInvoke = False
+        self.rootdir = None
+        self._duplicateBasedir = None
+        self._duplicateDirname = None
+        self.encoding = encoding
+    def __del__(self):
+        self.cleanup()
+
+    def _vcs_help(self):
+        """
+        Return the command help string.
+        (Allows a simple test to see if the client is installed.)
+        """
+        pass
+    def _vcs_detect(self, path=None):
+        """
+        Detect whether a directory is revision controlled with this VCS.
+        """
+        return True
+    def _vcs_root(self, path):
+        """
+        Get the VCS root.  This is the default working directory for
+        future invocations.  You would normally set this to the root
+        directory for your VCS.
+        """
+        if os.path.isdir(path)==False:
+            path = os.path.dirname(path)
+            if path == "":
+                path = os.path.abspath(".")
+        return path
+    def _vcs_init(self, path):
+        """
+        Begin versioning the tree based at path.
+        """
+        pass
+    def _vcs_cleanup(self):
+        """
+        Remove any cruft that _vcs_init() created outside of the
+        versioned tree.
+        """
+        pass
+    def _vcs_get_user_id(self):
+        """
+        Get the VCS's suggested user id (e.g. "John Doe <jdoe@example.com>").
+        If the VCS has not been configured with a username, return None.
+        """
+        return None
+    def _vcs_set_user_id(self, value):
+        """
+        Set the VCS's suggested user id (e.g "John Doe <jdoe@example.com>").
+        This is run if the VCS has not been configured with a usename, so
+        that commits will have a reasonable FROM value.
+        """
+        raise SettingIDnotSupported
+    def _vcs_add(self, path):
+        """
+        Add the already created file at path to version control.
+        """
+        pass
+    def _vcs_remove(self, path):
+        """
+        Remove the file at path from version control.  Optionally
+        remove the file from the filesystem as well.
+        """
+        pass
+    def _vcs_update(self, path):
+        """
+        Notify the versioning system of changes to the versioned file
+        at path.
+        """
+        pass
+    def _vcs_get_file_contents(self, path, revision=None, binary=False):
+        """
+        Get the file contents as they were in a given revision.
+        Revision==None specifies the current revision.
+        """
+        assert revision == None, \
+            "The %s VCS does not support revision specifiers" % self.name
+        if binary == False:
+            f = codecs.open(os.path.join(self.rootdir, path), "r", self.encoding)
+        else:
+            f = open(os.path.join(self.rootdir, path), "rb")
+        contents = f.read()
+        f.close()
+        return contents
+    def _vcs_duplicate_repo(self, directory, revision=None):
+        """
+        Get the repository as it was in a given revision.
+        revision==None specifies the current revision.
+        dir specifies a directory to create the duplicate in.
+        """
+        shutil.copytree(self.rootdir, directory, True)
+    def _vcs_commit(self, commitfile, allow_empty=False):
+        """
+        Commit the current working directory, using the contents of
+        commitfile as the comment.  Return the name of the old
+        revision (or None if commits are not supported).
+        
+        If allow_empty == False, raise EmptyCommit if there are no
+        changes to commit.
+        """
+        return None
+    def _vcs_revision_id(self, index):
+        """
+        Return the name of the <index>th revision.  Index will be an
+        integer (possibly <= 0).  The choice of which branch to follow
+        when crossing branches/merges is not defined.
+
+        Return None if revision IDs are not supported, or if the
+        specified revision does not exist.
+        """
+        return None
+    def installed(self):
+        try:
+            self._vcs_help()
+            return True
+        except OSError, e:
+            if e.errno == errno.ENOENT:
+                return False
+        except CommandError:
+            return False
+    def detect(self, path="."):
+        """
+        Detect whether a directory is revision controlled with this VCS.
+        """
+        return self._vcs_detect(path)
+    def root(self, path):
+        """
+        Set the root directory to the path's VCS root.  This is the
+        default working directory for future invocations.
+        """
+        self.rootdir = self._vcs_root(path)
+    def init(self, path):
+        """
+        Begin versioning the tree based at path.
+        Also roots the vcs at path.
+        """
+        if os.path.isdir(path)==False:
+            path = os.path.dirname(path)
+        self._vcs_init(path)
+        self.root(path)
+    def cleanup(self):
+        self._vcs_cleanup()
+    def get_user_id(self):
+        """
+        Get the VCS's suggested user id (e.g. "John Doe <jdoe@example.com>").
+        If the VCS has not been configured with a username, return the user's
+        id.  You can override the automatic lookup procedure by setting the
+        VCS.user_id attribute to a string of your choice.
+        """
+        if hasattr(self, "user_id"):
+            if self.user_id != None:
+                return self.user_id
+        id = self._vcs_get_user_id()
+        if id == None:
+            name = self._u_get_fallback_username()
+            email = self._u_get_fallback_email()
+            id = self._u_create_id(name, email)
+            print >> sys.stderr, "Guessing id '%s'" % id
+            try:
+                self.set_user_id(id)
+            except SettingIDnotSupported:
+                pass
+        return id
+    def set_user_id(self, value):
+        """
+        Set the VCS's suggested user id (e.g "John Doe <jdoe@example.com>").
+        This is run if the VCS has not been configured with a usename, so
+        that commits will have a reasonable FROM value.
+        """
+        self._vcs_set_user_id(value)
+    def add(self, path):
+        """
+        Add the already created file at path to version control.
+        """
+        self._vcs_add(self._u_rel_path(path))
+    def remove(self, path):
+        """
+        Remove a file from both version control and the filesystem.
+        """
+        self._vcs_remove(self._u_rel_path(path))
+        if os.path.exists(path):
+            os.remove(path)
+    def recursive_remove(self, dirname):
+        """
+        Remove a file/directory and all its decendents from both
+        version control and the filesystem.
+        """
+        if not os.path.exists(dirname):
+            raise NoSuchFile(dirname)
+        for dirpath,dirnames,filenames in os.walk(dirname, topdown=False):
+            filenames.extend(dirnames)
+            for path in filenames:
+                fullpath = os.path.join(dirpath, path)
+                if os.path.exists(fullpath) == False:
+                    continue
+                self._vcs_remove(self._u_rel_path(fullpath))
+        if os.path.exists(dirname):
+            shutil.rmtree(dirname)
+    def update(self, path):
+        """
+        Notify the versioning system of changes to the versioned file
+        at path.
+        """
+        self._vcs_update(self._u_rel_path(path))
+    def get_file_contents(self, path, revision=None, allow_no_vcs=False, binary=False):
+        """
+        Get the file as it was in a given revision.
+        Revision==None specifies the current revision.
+        """
+        if not os.path.exists(path):
+            raise NoSuchFile(path)
+        if self._use_vcs(path, allow_no_vcs):
+            relpath = self._u_rel_path(path)
+            contents = self._vcs_get_file_contents(relpath,revision,binary=binary)
+        else:
+            f = codecs.open(path, "r", self.encoding)
+            contents = f.read()
+            f.close()
+        return contents
+    def set_file_contents(self, path, contents, allow_no_vcs=False, binary=False):
+        """
+        Set the file contents under version control.
+        """
+        add = not os.path.exists(path)
+        if binary == False:
+            f = codecs.open(path, "w", self.encoding)
+        else:
+            f = open(path, "wb")
+        f.write(contents)
+        f.close()
+        
+        if self._use_vcs(path, allow_no_vcs):
+            if add:
+                self.add(path)
+            else:
+                self.update(path)
+    def mkdir(self, path, allow_no_vcs=False, check_parents=True):
+        """
+        Create (if neccessary) a directory at path under version
+        control.
+        """
+        if check_parents == True:
+            parent = os.path.dirname(path)
+            if not os.path.exists(parent): # recurse through parents
+                self.mkdir(parent, allow_no_vcs, check_parents)
+        if not os.path.exists(path):
+            os.mkdir(path)
+            if self._use_vcs(path, allow_no_vcs):
+                self.add(path)
+        else:
+            assert os.path.isdir(path)
+            if self._use_vcs(path, allow_no_vcs):
+                #self.update(path)# Don't update directories.  Changing files
+                pass              # underneath them should be sufficient.
+                
+    def duplicate_repo(self, revision=None):
+        """
+        Get the repository as it was in a given revision.
+        revision==None specifies the current revision.
+        Return the path to the arbitrary directory at the base of the new repo.
+        """
+        # Dirname in Baseir to protect against simlink attacks.
+        if self._duplicateBasedir == None:
+            self._duplicateBasedir = tempfile.mkdtemp(prefix='BEvcs')
+            self._duplicateDirname = \
+                os.path.join(self._duplicateBasedir, "duplicate")
+            self._vcs_duplicate_repo(directory=self._duplicateDirname,
+                                     revision=revision)
+        return self._duplicateDirname
+    def remove_duplicate_repo(self):
+        """
+        Clean up a duplicate repo created with duplicate_repo().
+        """
+        if self._duplicateBasedir != None:
+            shutil.rmtree(self._duplicateBasedir)
+            self._duplicateBasedir = None
+            self._duplicateDirname = None
+    def commit(self, summary, body=None, allow_empty=False):
+        """
+        Commit the current working directory, with a commit message
+        string summary and body.  Return the name of the old revision
+        (or None if versioning is not supported).
+        
+        If allow_empty == False (the default), raise EmptyCommit if
+        there are no changes to commit.
+        """
+        summary = summary.strip()+'\n'
+        if body is not None:
+            summary += '\n' + body.strip() + '\n'
+        descriptor, filename = tempfile.mkstemp()
+        revision = None
+        try:
+            temp_file = os.fdopen(descriptor, 'wb')
+            temp_file.write(summary)
+            temp_file.flush()
+            self.precommit()
+            revision = self._vcs_commit(filename, allow_empty=allow_empty)
+            temp_file.close()
+            self.postcommit()
+        finally:
+            os.remove(filename)
+        return revision
+    def precommit(self):
+        """
+        Executed before all attempted commits.
+        """
+        pass
+    def postcommit(self):
+        """
+        Only executed after successful commits.
+        """
+        pass
+    def revision_id(self, index=None):
+        """
+        Return the name of the <index>th revision.  The choice of
+        which branch to follow when crossing branches/merges is not
+        defined.
+
+        Return None if index==None, revision IDs are not supported, or
+        if the specified revision does not exist.
+        """
+        if index == None:
+            return None
+        return self._vcs_revision_id(index)
+    def _u_any_in_string(self, list, string):
+        """
+        Return True if any of the strings in list are in string.
+        Otherwise return False.
+        """
+        for list_string in list:
+            if list_string in string:
+                return True
+        return False
+    def _u_invoke(self, args, stdin=None, expect=(0,), cwd=None):
+        """
+        expect should be a tuple of allowed exit codes.  cwd should be
+        the directory from which the command will be executed.
+        """
+        if cwd == None:
+            cwd = self.rootdir
+        if self.verboseInvoke == True:
+            print >> sys.stderr, "%s$ %s" % (cwd, " ".join(args))
+        try :
+            if sys.platform != "win32":
+                q = Popen(args, stdin=PIPE, stdout=PIPE, stderr=PIPE, cwd=cwd)
+            else:
+                # win32 don't have os.execvp() so have to run command in a shell
+                q = Popen(args, stdin=PIPE, stdout=PIPE, stderr=PIPE, 
+                          shell=True, cwd=cwd)
+        except OSError, e :
+            raise CommandError(args, status=e.args[0], stdout="", stderr=e)
+        output,error = q.communicate(input=stdin)
+        status = q.wait()
+        if self.verboseInvoke == True:
+            print >> sys.stderr, "%d\n%s%s" % (status, output, error)
+        if status not in expect:
+            raise CommandError(args, status, output, error)
+        return status, output, error
+    def _u_invoke_client(self, *args, **kwargs):
+        directory = kwargs.get('directory',None)
+        expect = kwargs.get('expect', (0,))
+        stdin = kwargs.get('stdin', None)
+        cl_args = [self.client]
+        cl_args.extend(args)
+        return self._u_invoke(cl_args, stdin=stdin,expect=expect,cwd=directory)
+    def _u_search_parent_directories(self, path, filename):
+        """
+        Find the file (or directory) named filename in path or in any
+        of path's parents.
+        
+        e.g.
+          search_parent_directories("/a/b/c", ".be")
+        will return the path to the first existing file from
+          /a/b/c/.be
+          /a/b/.be
+          /a/.be
+          /.be
+        or None if none of those files exist.
+        """
+        return search_parent_directories(path, filename)
+    def _use_vcs(self, path, allow_no_vcs):
+        """
+        Try and decide if _vcs_add/update/mkdir/etc calls will
+        succeed.  Returns True is we think the vcs_call would
+        succeeed, and False otherwise.
+        """
+        use_vcs = True
+        exception = None
+        if self.rootdir != None:
+            if self.path_in_root(path) == False:
+                use_vcs = False
+                exception = PathNotInRoot(path, self.rootdir)
+        else:
+            use_vcs = False
+            exception = VCSnotRooted
+        if use_vcs == False and allow_no_vcs==False:
+            raise exception
+        return use_vcs
+    def path_in_root(self, path, root=None):
+        """
+        Return the relative path to path from root.
+        >>> vcs = new()
+        >>> vcs.path_in_root("/a.b/c/.be", "/a.b/c")
+        True
+        >>> vcs.path_in_root("/a.b/.be", "/a.b/c")
+        False
+        """
+        if root == None:
+            if self.rootdir == None:
+                raise VCSnotRooted
+            root = self.rootdir
+        path = os.path.abspath(path)
+        absRoot = os.path.abspath(root)
+        absRootSlashedDir = os.path.join(absRoot,"")
+        if not path.startswith(absRootSlashedDir):
+            return False
+        return True
+    def _u_rel_path(self, path, root=None):
+        """
+        Return the relative path to path from root.
+        >>> vcs = new()
+        >>> vcs._u_rel_path("/a.b/c/.be", "/a.b/c")
+        '.be'
+        """
+        if root == None:
+            if self.rootdir == None:
+                raise VCSnotRooted
+            root = self.rootdir
+        path = os.path.abspath(path)
+        absRoot = os.path.abspath(root)
+        absRootSlashedDir = os.path.join(absRoot,"")
+        if not path.startswith(absRootSlashedDir):
+            raise PathNotInRoot(path, absRootSlashedDir)
+        assert path != absRootSlashedDir, \
+            "file %s == root directory %s" % (path, absRootSlashedDir)
+        relpath = path[len(absRootSlashedDir):]
+        return relpath
+    def _u_abspath(self, path, root=None):
+        """
+        Return the absolute path from a path realtive to root.
+        >>> vcs = new()
+        >>> vcs._u_abspath(".be", "/a.b/c")
+        '/a.b/c/.be'
+        """
+        if root == None:
+            assert self.rootdir != None, "VCS not rooted"
+            root = self.rootdir
+        return os.path.abspath(os.path.join(root, path))
+    def _u_create_id(self, name, email=None):
+        """
+        >>> vcs = new()
+        >>> vcs._u_create_id("John Doe", "jdoe@example.com")
+        'John Doe <jdoe@example.com>'
+        >>> vcs._u_create_id("John Doe")
+        'John Doe'
+        """
+        assert len(name) > 0
+        if email == None or len(email) == 0:
+            return name
+        else:
+            return "%s <%s>" % (name, email)
+    def _u_parse_id(self, value):
+        """
+        >>> vcs = new()
+        >>> vcs._u_parse_id("John Doe <jdoe@example.com>")
+        ('John Doe', 'jdoe@example.com')
+        >>> vcs._u_parse_id("John Doe")
+        ('John Doe', None)
+        >>> try:
+        ...     vcs._u_parse_id("John Doe <jdoe@example.com><what?>")
+        ... except AssertionError:
+        ...     print "Invalid match"
+        Invalid match
+        """
+        emailexp = re.compile("(.*) <([^>]*)>(.*)")
+        match = emailexp.search(value)
+        if match == None:
+            email = None
+            name = value
+        else:
+            assert len(match.groups()) == 3
+            assert match.groups()[2] == "", match.groups()
+            email = match.groups()[1]
+            name = match.groups()[0]
+        assert name != None
+        assert len(name) > 0
+        return (name, email)
+    def _u_get_fallback_username(self):
+        name = None
+        for envariable in ["LOGNAME", "USERNAME"]:
+            if os.environ.has_key(envariable):
+                name = os.environ[envariable]
+                break
+        assert name != None
+        return name
+    def _u_get_fallback_email(self):
+        hostname = gethostname()
+        name = self._u_get_fallback_username()
+        return "%s@%s" % (name, hostname)
+    def _u_parse_commitfile(self, commitfile):
+        """
+        Split the commitfile created in self.commit() back into
+        summary and header lines.
+        """
+        f = codecs.open(commitfile, "r", self.encoding)
+        summary = f.readline()
+        body = f.read()
+        body.lstrip('\n')
+        if len(body) == 0:
+            body = None
+        f.close()
+        return (summary, body)
+        
+
+def setup_vcs_test_fixtures(testcase):
+    """Set up test fixtures for VCS test case."""
+    testcase.vcs = testcase.Class()
+    testcase.dir = Dir()
+    testcase.dirname = testcase.dir.path
+
+    vcs_not_supporting_uninitialized_user_id = []
+    vcs_not_supporting_set_user_id = ["None", "hg"]
+    testcase.vcs_supports_uninitialized_user_id = (
+        testcase.vcs.name not in vcs_not_supporting_uninitialized_user_id)
+    testcase.vcs_supports_set_user_id = (
+        testcase.vcs.name not in vcs_not_supporting_set_user_id)
+
+    if not testcase.vcs.installed():
+        testcase.fail(
+            "%(name)s VCS not found" % vars(testcase.Class))
+
+    if testcase.Class.name != "None":
+        testcase.failIf(
+            testcase.vcs.detect(testcase.dirname),
+            "Detected %(name)s VCS before initialising"
+                % vars(testcase.Class))
+
+    testcase.vcs.init(testcase.dirname)
+
+
+class VCSTestCase(unittest.TestCase):
+    """Test cases for base VCS class."""
+
+    Class = VCS
+
+    def __init__(self, *args, **kwargs):
+        super(VCSTestCase, self).__init__(*args, **kwargs)
+        self.dirname = None
+
+    def setUp(self):
+        super(VCSTestCase, self).setUp()
+        setup_vcs_test_fixtures(self)
+
+    def tearDown(self):
+        del(self.vcs)
+        super(VCSTestCase, self).tearDown()
+
+    def full_path(self, rel_path):
+        return os.path.join(self.dirname, rel_path)
+
+
+class VCS_init_TestCase(VCSTestCase):
+    """Test cases for VCS.init method."""
+
+    def test_detect_should_succeed_after_init(self):
+        """Should detect VCS in directory after initialization."""
+        self.failUnless(
+            self.vcs.detect(self.dirname),
+            "Did not detect %(name)s VCS after initialising"
+                % vars(self.Class))
+
+    def test_vcs_rootdir_in_specified_root_path(self):
+        """VCS root directory should be in specified root path."""
+        rp = os.path.realpath(self.vcs.rootdir)
+        dp = os.path.realpath(self.dirname)
+        vcs_name = self.Class.name
+        self.failUnless(
+            dp == rp or rp == None,
+            "%(vcs_name)s VCS root in wrong dir (%(dp)s %(rp)s)" % vars())
+
+
+class VCS_get_user_id_TestCase(VCSTestCase):
+    """Test cases for VCS.get_user_id method."""
+
+    def test_gets_existing_user_id(self):
+        """Should get the existing user ID."""
+        if not self.vcs_supports_uninitialized_user_id:
+            return
+
+        user_id = self.vcs.get_user_id()
+        self.failUnless(
+            user_id is not None,
+            "unable to get a user id")
+
+
+class VCS_set_user_id_TestCase(VCSTestCase):
+    """Test cases for VCS.set_user_id method."""
+
+    def setUp(self):
+        super(VCS_set_user_id_TestCase, self).setUp()
+
+        if self.vcs_supports_uninitialized_user_id:
+            self.prev_user_id = self.vcs.get_user_id()
+        else:
+            self.prev_user_id = "Uninitialized identity <bogus@example.org>"
+
+        if self.vcs_supports_set_user_id:
+            self.test_new_user_id = "John Doe <jdoe@example.com>"
+            self.vcs.set_user_id(self.test_new_user_id)
+
+    def tearDown(self):
+        if self.vcs_supports_set_user_id:
+            self.vcs.set_user_id(self.prev_user_id)
+        super(VCS_set_user_id_TestCase, self).tearDown()
+
+    def test_raises_error_in_unsupported_vcs(self):
+        """Should raise an error in a VCS that doesn't support it."""
+        if self.vcs_supports_set_user_id:
+            return
+        self.assertRaises(
+            SettingIDnotSupported,
+            self.vcs.set_user_id, "foo")
+
+    def test_updates_user_id_in_supporting_vcs(self):
+        """Should update the user ID in an VCS that supports it."""
+        if not self.vcs_supports_set_user_id:
+            return
+        user_id = self.vcs.get_user_id()
+        self.failUnlessEqual(
+            self.test_new_user_id, user_id,
+            "user id not set correctly (expected %s, got %s)"
+                % (self.test_new_user_id, user_id))
+
+
+def setup_vcs_revision_test_fixtures(testcase):
+    """Set up revision test fixtures for VCS test case."""
+    testcase.test_dirs = ['a', 'a/b', 'c']
+    for path in testcase.test_dirs:
+        testcase.vcs.mkdir(testcase.full_path(path))
+
+    testcase.test_files = ['a/text', 'a/b/text']
+
+    testcase.test_contents = {
+        'rev_1': "Lorem ipsum",
+        'uncommitted': "dolor sit amet",
+        }
+
+
+class VCS_mkdir_TestCase(VCSTestCase):
+    """Test cases for VCS.mkdir method."""
+
+    def setUp(self):
+        super(VCS_mkdir_TestCase, self).setUp()
+        setup_vcs_revision_test_fixtures(self)
+
+    def tearDown(self):
+        for path in reversed(sorted(self.test_dirs)):
+            self.vcs.recursive_remove(self.full_path(path))
+        super(VCS_mkdir_TestCase, self).tearDown()
+
+    def test_mkdir_creates_directory(self):
+        """Should create specified directory in filesystem."""
+        for path in self.test_dirs:
+            full_path = self.full_path(path)
+            self.failUnless(
+                os.path.exists(full_path),
+                "path %(full_path)s does not exist" % vars())
+
+
+class VCS_commit_TestCase(VCSTestCase):
+    """Test cases for VCS.commit method."""
+
+    def setUp(self):
+        super(VCS_commit_TestCase, self).setUp()
+        setup_vcs_revision_test_fixtures(self)
+
+    def tearDown(self):
+        for path in reversed(sorted(self.test_dirs)):
+            self.vcs.recursive_remove(self.full_path(path))
+        super(VCS_commit_TestCase, self).tearDown()
+
+    def test_file_contents_as_specified(self):
+        """Should set file contents as specified."""
+        test_contents = self.test_contents['rev_1']
+        for path in self.test_files:
+            full_path = self.full_path(path)
+            self.vcs.set_file_contents(full_path, test_contents)
+            current_contents = self.vcs.get_file_contents(full_path)
+            self.failUnlessEqual(test_contents, current_contents)
+
+    def test_file_contents_as_committed(self):
+        """Should have file contents as specified after commit."""
+        test_contents = self.test_contents['rev_1']
+        for path in self.test_files:
+            full_path = self.full_path(path)
+            self.vcs.set_file_contents(full_path, test_contents)
+            revision = self.vcs.commit("Initial file contents.")
+            current_contents = self.vcs.get_file_contents(full_path)
+            self.failUnlessEqual(test_contents, current_contents)
+
+    def test_file_contents_as_set_when_uncommitted(self):
+        """Should set file contents as specified after commit."""
+        if not self.vcs.versioned:
+            return
+        for path in self.test_files:
+            full_path = self.full_path(path)
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['rev_1'])
+            revision = self.vcs.commit("Initial file contents.")
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['uncommitted'])
+            current_contents = self.vcs.get_file_contents(full_path)
+            self.failUnlessEqual(
+                self.test_contents['uncommitted'], current_contents)
+
+    def test_revision_file_contents_as_committed(self):
+        """Should get file contents as committed to specified revision."""
+        if not self.vcs.versioned:
+            return
+        for path in self.test_files:
+            full_path = self.full_path(path)
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['rev_1'])
+            revision = self.vcs.commit("Initial file contents.")
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['uncommitted'])
+            committed_contents = self.vcs.get_file_contents(
+                full_path, revision)
+            self.failUnlessEqual(
+                self.test_contents['rev_1'], committed_contents)
+
+    def test_revision_id_as_committed(self):
+        """Check for compatibility between .commit() and .revision_id()"""
+        if not self.vcs.versioned:
+            self.failUnlessEqual(self.vcs.revision_id(5), None)
+            return
+        committed_revisions = []
+        for path in self.test_files:
+            full_path = self.full_path(path)
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['rev_1'])
+            revision = self.vcs.commit("Initial %s contents." % path)
+            committed_revisions.append(revision)
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['uncommitted'])
+            revision = self.vcs.commit("Altered %s contents." % path)
+            committed_revisions.append(revision)
+        for i,revision in enumerate(committed_revisions):
+            self.failUnlessEqual(self.vcs.revision_id(i), revision)
+            i += -len(committed_revisions) # check negative indices
+            self.failUnlessEqual(self.vcs.revision_id(i), revision)
+        i = len(committed_revisions)
+        self.failUnlessEqual(self.vcs.revision_id(i), None)
+        self.failUnlessEqual(self.vcs.revision_id(-i-1), None)
+
+    def test_revision_id_as_committed(self):
+        """Check revision id before first commit"""
+        if not self.vcs.versioned:
+            self.failUnlessEqual(self.vcs.revision_id(5), None)
+            return
+        committed_revisions = []
+        for path in self.test_files:
+            self.failUnlessEqual(self.vcs.revision_id(0), None)
+
+
+class VCS_duplicate_repo_TestCase(VCSTestCase):
+    """Test cases for VCS.duplicate_repo method."""
+
+    def setUp(self):
+        super(VCS_duplicate_repo_TestCase, self).setUp()
+        setup_vcs_revision_test_fixtures(self)
+
+    def tearDown(self):
+        self.vcs.remove_duplicate_repo()
+        for path in reversed(sorted(self.test_dirs)):
+            self.vcs.recursive_remove(self.full_path(path))
+        super(VCS_duplicate_repo_TestCase, self).tearDown()
+
+    def test_revision_file_contents_as_committed(self):
+        """Should match file contents as committed to specified revision."""
+        if not self.vcs.versioned:
+            return
+        for path in self.test_files:
+            full_path = self.full_path(path)
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['rev_1'])
+            revision = self.vcs.commit("Commit current status")
+            self.vcs.set_file_contents(
+                full_path, self.test_contents['uncommitted'])
+            dup_repo_path = self.vcs.duplicate_repo(revision)
+            dup_file_path = os.path.join(dup_repo_path, path)
+            dup_file_contents = file(dup_file_path, 'rb').read()
+            self.failUnlessEqual(
+                self.test_contents['rev_1'], dup_file_contents)
+            self.vcs.remove_duplicate_repo()
+
+
+def make_vcs_testcase_subclasses(vcs_class, namespace):
+    """Make VCSTestCase subclasses for vcs_class in the namespace."""
+    vcs_testcase_classes = [
+        c for c in (
+            ob for ob in globals().values() if isinstance(ob, type))
+        if issubclass(c, VCSTestCase)]
+
+    for base_class in vcs_testcase_classes:
+        testcase_class_name = vcs_class.__name__ + base_class.__name__
+        testcase_class_bases = (base_class,)
+        testcase_class_dict = dict(base_class.__dict__)
+        testcase_class_dict['Class'] = vcs_class
+        testcase_class = type(
+            testcase_class_name, testcase_class_bases, testcase_class_dict)
+        setattr(namespace, testcase_class_name, testcase_class)
+
+
+unitsuite = unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
+suite = unittest.TestSuite([unitsuite, doctest.DocTestSuite()])
diff --git a/interfaces/web/Bugs-Everywhere-Web/libbe/version.py b/interfaces/web/Bugs-Everywhere-Web/libbe/version.py
new file mode 100644
index 0000000..f8eebbd
--- /dev/null
+++ b/interfaces/web/Bugs-Everywhere-Web/libbe/version.py
@@ -0,0 +1,50 @@
+#!/usr/bin/env python
+# Copyright (C) 2009 W. Trevor King <wking@drexel.edu>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+"""
+Store version info for this BE installation.  By default, use the
+bzr-generated information in _version.py, but allow manual overriding
+by setting _VERSION.  This allows support of both the "I don't want to
+be bothered setting version strings" and the "I want complete control
+over the version strings" workflows.
+"""
+
+import libbe._version as _version
+
+# Manually set a version string (optional, defaults to bzr revision id)
+#_VERSION = "1.2.3"
+
+def version(verbose=False):
+    """
+    Returns the version string for this BE installation.  If
+    verbose==True, the string will include extra lines with more
+    detail (e.g. bzr branch nickname, etc.).
+    """
+    if "_VERSION" in globals():
+        string = _VERSION
+    else:
+        string = _version.version_info["revision_id"]
+    if verbose == True:
+        string += ("\n"
+                   "revision: %(revno)d\n"
+                   "nick: %(branch_nick)s\n"
+                   "revision id: %(revision_id)s"
+                   % _version.version_info)
+    return string
+
+if __name__ == "__main__":
+    print version(verbose=True)