conversion of cmp() function

12 files changed, 205 insertions, 176 deletions

diff --git a/libbe/bug.py b/libbe/bug.py
index a4ef53d..d211c30 100644
--- a/libbe/bug.py
+++ b/libbe/bug.py
@@ -25,16 +25,8 @@
 """
 
 import copy
-import os
-import os.path
-import errno
-import sys
 import time
-import types
-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.etree import ElementTree
 import xml.sax.saxutils
 
 import libbe
@@ -47,7 +39,7 @@ import libbe.storage.util.mapfile as mapfile
 import libbe.comment as comment
 import libbe.util.utility as utility
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     import doctest
 
 
@@ -86,7 +78,7 @@ def load_severities(severity_def):
     global severity_values
     global severity_description
     global severity_index
-    if severity_def == None:
+    if severity_def is None:
         return
     severity_values = tuple([val for val,description in severity_def])
     severity_description = dict(severity_def)
@@ -95,6 +87,12 @@ def load_severities(severity_def):
         severity_index[severity] = i
 load_severities(severity_def)
 
+
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
 active_status_values = []
 inactive_status_values = []
 status_values = []
@@ -106,9 +104,9 @@ def load_status(active_status_def, inactive_status_def):
     global status_values
     global status_description
     global status_index
-    if active_status_def == None:
+    if active_status_def is None:
         active_status_def = globals()["active_status_def"]
-    if inactive_status_def == None:
+    if inactive_status_def is None:
         inactive_status_def = globals()["inactive_status_def"]
     active_status_values = tuple([val for val,description in active_status_def])
     inactive_status_values = tuple([val for val,description in inactive_status_def])
@@ -197,7 +195,7 @@ class Bug (settings_object.SavedSettingsObject):
     def time_string(): return {}
 
     def _get_time(self):
-        if self.time_string == None:
+        if self.time_string is None:
             self._cached_time_string = None
             self._cached_time = None
             return None
@@ -253,7 +251,7 @@ class Bug (settings_object.SavedSettingsObject):
         self.uuid = uuid
         self.id = libbe.util.id.ID(self, 'bug')
         if from_storage == False:
-            if uuid == None:
+            if uuid is None:
                 self.uuid = libbe.util.id.uuid_gen()
             self.time = int(time.time()) # only save to second precision
             self.summary = summary
@@ -277,7 +275,7 @@ class Bug (settings_object.SavedSettingsObject):
 
     def _setting_attr_string(self, setting):
         value = getattr(self, setting)
-        if value == None:
+        if value is None:
             return ""
         if type(value) not in (str,):
             return str(value)
@@ -285,7 +283,7 @@ class Bug (settings_object.SavedSettingsObject):
 
     def string(self, shortlist=False, show_comments=False):
         if shortlist == False:
-            if self.time == None:
+            if self.time is None:
                 timestring = ""
             else:
                 htime = utility.handy_time(self.time)
@@ -309,7 +307,7 @@ class Bug (settings_object.SavedSettingsObject):
             chars = "%c%c" % (statuschar, severitychar)
             bugout = "%s:%s: %s" % (self.id.user(),chars,self.summary.rstrip('\n'))
 
-        if show_comments == True:
+        if show_comments:
             self.comment_root.sort(cmp=libbe.comment.cmp_time, reverse=True)
             comout = self.comment_root.string_thread(flatten=False)
             output = bugout + '\n' + comout.rstrip('\n')
@@ -409,7 +407,7 @@ class Bug (settings_object.SavedSettingsObject):
             </comment>
           </bug>
         """
-        if self.time == None:
+        if self.time is None:
             timestring = ""
         else:
             timestring = utility.time_to_str(self.time)
@@ -429,7 +427,7 @@ class Bug (settings_object.SavedSettingsObject):
                 lines.append('  <%s>%s</%s>' % (k,xml.sax.saxutils.escape(v),k))
         for estr in self.extra_strings:
             lines.append('  <extra-string>%s</extra-string>' % estr)
-        if show_comments == True:
+        if show_comments:
             comout = self.comment_root.xml_thread(indent=indent+2)
             if comout:
                 comout = comout[indent:]  # strip leading indent spaces
@@ -588,7 +586,7 @@ class Bug (settings_object.SavedSettingsObject):
         default parent via default_parent.
         """
         uuid_map = {}
-        if default_parent == None:
+        if default_parent is None:
             default_parent = self.comment_root
         for c in list(self.comments()) + comments:
             assert c.uuid != None
@@ -609,7 +607,7 @@ class Bug (settings_object.SavedSettingsObject):
             try:
                 parent = uuid_map[c.in_reply_to]
             except KeyError:
-                if ignore_missing_references == True:
+                if ignore_missing_references:
                     libbe.LOG.warning(
                         'ignoring missing reference to {0}'.format(
                             c.in_reply_to))
@@ -715,9 +713,9 @@ class Bug (settings_object.SavedSettingsObject):
                              ).format(attr, old, new, self.uuid))
         for estr in other.extra_strings:
             if not estr in self.extra_strings:
-                if accept_extra_strings == True:
+                if accept_extra_strings:
                     self.extra_strings += [estr]
-                elif change_exception == True:
+                elif change_exception:
                     raise ValueError('Merge would add extra string "%s" for bug %s' \
                         % (estr, self.uuid))
         for o_comm in other.comments():
@@ -728,13 +726,13 @@ class Bug (settings_object.SavedSettingsObject):
                     s_comm = self.comment_root.comment_from_uuid(o_comm.alt_id)
                 except KeyError as e:
                     s_comm = None
-            if s_comm == None:
-                if accept_comments == True:
+            if s_comm is None:
+                if accept_comments:
                     o_comm_copy = copy.copy(o_comm)
                     o_comm_copy.bug = self
                     o_comm_copy.id = libbe.util.id.ID(o_comm_copy, 'comment')
                     self.comment_root.add_reply(o_comm_copy)
-                elif change_exception == True:
+                elif change_exception:
                     raise ValueError('Merge would add comment %s (alt: %s) to bug %s' \
                         % (o_comm.uuid, o_comm.alt_id, self.uuid))
             else:
@@ -745,7 +743,7 @@ class Bug (settings_object.SavedSettingsObject):
     # methods for saving/loading/acessing settings and properties.
 
     def load_settings(self, settings_mapfile=None):
-        if settings_mapfile == None:
+        if settings_mapfile is None:
             settings_mapfile = self.storage.get(
                 self.id.storage('values'), '{}\n')
         try:
@@ -782,7 +780,7 @@ class Bug (settings_object.SavedSettingsObject):
             comment.save_comments(self)
 
     def load_comments(self, load_full=True):
-        if load_full == True:
+        if load_full:
             # Force a complete load of the whole comment tree
             self.comment_root = self._get_comment_root(load_full=True)
         else:
@@ -895,8 +893,8 @@ def cmp_attr(bug_1, bug_2, attr, invert=False):
         return 1
     val_1 = getattr(bug_1, attr)
     val_2 = getattr(bug_2, attr)
-    if val_1 == None: val_1 = None
-    if val_2 == None: val_2 = None
+    if val_1 is None: val_1 = None
+    if val_2 is None: val_2 = None
 
     if invert == True :
         return -cmp(val_1, val_2)
@@ -970,5 +968,5 @@ def cmp_last_modified(bug_1, bug_2):
     return -cmp(val_1, val_2)
 
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     suite = doctest.DocTestSuite()
diff --git a/libbe/command/html.py b/libbe/command/html.py
index df87450..ed43808 100644
--- a/libbe/command/html.py
+++ b/libbe/command/html.py
@@ -21,14 +21,11 @@
 # You should have received a copy of the GNU General Public License along with
 # Bugs Everywhere.  If not, see <http://www.gnu.org/licenses/>.
 
-import codecs
 import email.utils
-import html.entities
 import itertools
 import os
 import os.path
 import re
-import string
 import time
 import xml.sax.saxutils
 
@@ -81,7 +78,7 @@ class ServerApp (libbe.util.wsgi.WSGI_AppObject,
             }
 
     # handlers
-    def style(self, environ, start_response): 
+    def style(self, environ, start_response):
         template = self.template.get_template('style.css')
         content = template.render()
         return self.ok_response(
@@ -125,7 +122,7 @@ class ServerApp (libbe.util.wsgi.WSGI_AppObject,
                             self.bugdirs, target)))
                 for target in bugs]
         else:
-            template = self.template.get_template('standard_index.html')           
+            template = self.template.get_template('standard_index.html')
         content = template.render(template_info)+'\n'
         return self.ok_response(
             environ, start_response, content, content_type='text/html')
@@ -351,7 +348,7 @@ div.main {
   margin-top: 1em;
   background-color: #fcfcfc;
   border-radius: 10px;
-  
+
 }
 
 div.footer {
@@ -397,7 +394,7 @@ table {
   border-spacing: 0px 0px;
   width: auto;
   padding: 0px;
-  
+
   }
 
 tb { border: 1px; }
@@ -463,14 +460,14 @@ td.tab {
 td.sel.tab {
     background-color: #c3d9ff ;
     border: 1px solid #c3d9ff;
-    font-weight:bold;    
+    font-weight:bold;
     border-top-left-radius: 15px;
     border-top-right-radius: 15px;
 }
 
-td.nsel.tab { 
+td.nsel.tab {
     border: 1px solid #c3d9ff;
-    font-weight:bold;    
+    font-weight:bold;
     border-top-left-radius: 5px;
     border-top-right-radius: 5px;
 }
@@ -480,7 +477,7 @@ table.bug_list {
     border-style: solid;
     border-color: #c3d9ff;
     padding: 0px;
-    width: 100%;            
+    width: 100%;
     border: 1px solid #c3d9ff;
 }
 
@@ -917,7 +914,7 @@ will exit after the dump without serving anything over the wire.
                 for url_,path_ in url_mappings:
                     content = content.replace(url_, path_)
                 if not os.path.isdir(bug_dir_path):
-                    self._make_dir(bug_dir_path)                    
+                    self._make_dir(bug_dir_path)
                 self._write_file(content=content, path_array=path_array)
 
     def _get_content(self, caller, app, path, data_dict=None):
diff --git a/libbe/command/merge.py b/libbe/command/merge.py
index 85fbb60..cf9eb91 100644
--- a/libbe/command/merge.py
+++ b/libbe/command/merge.py
@@ -18,7 +18,6 @@
 # Bugs Everywhere.  If not, see <http://www.gnu.org/licenses/>.
 
 import copy
-import os
 
 import libbe
 import libbe.command
@@ -67,8 +66,8 @@ class Merge (libbe.command.Command):
       Short name : abc/a
         Severity : minor
           Status : open
-        Assigned : 
-        Reporter : 
+        Assigned :
+        Reporter :
          Creator : John Doe <jdoe@example.com>
          Created : ...
     Bug A
@@ -114,8 +113,8 @@ class Merge (libbe.command.Command):
       Short name : abc/b
         Severity : minor
           Status : closed
-        Assigned : 
-        Reporter : 
+        Assigned :
+        Reporter :
          Creator : Jane Doe <jdoe@example.com>
          Created : ...
     Bug B
diff --git a/libbe/comment.py b/libbe/comment.py
index d03f8ce..ca5f884 100644
--- a/libbe/comment.py
+++ b/libbe/comment.py
@@ -23,11 +23,7 @@
 """
 
 import base64
-import os
-import os.path
-import sys
 import time
-import types
 try:
     from email.mime.base import MIMEBase
     from email.encoders import encode_base64
@@ -35,10 +31,7 @@ except ImportError:
     # adjust to old python 2.4
     from email.MIMEBase import MIMEBase
     from email.Encoders import encode_base64
-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.etree import ElementTree
 import xml.sax.saxutils
 
 import libbe
@@ -51,10 +44,15 @@ import libbe.storage.util.mapfile as mapfile
 from libbe.util.tree import Tree
 import libbe.util.utility as utility
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     import doctest
 
 
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
 class MissingReference(ValueError):
     def __init__(self, comment):
         msg = "Missing reference to %s" % (comment.in_reply_to)
@@ -77,7 +75,7 @@ def load_comments(bug, load_full=False):
     comments = []
     for uuid in uuids:
         comm = Comment(bug, uuid, from_storage=True)
-        if load_full == True:
+        if load_full:
             comm.load_settings()
             dummy = comm.body # force the body to load
         comments.append(comm)
@@ -141,7 +139,7 @@ class Comment (Tree, settings_object.SavedSettingsObject):
     def date(): return {}
 
     def _get_time(self):
-        if self.date == None:
+        if self.date is None:
             return None
         return utility.str_to_time(self.date)
     def _set_time(self, value):
@@ -211,7 +209,7 @@ class Comment (Tree, settings_object.SavedSettingsObject):
         self.uuid = uuid
         self.id = libbe.util.id.ID(self, 'comment')
         if from_storage == False:
-            if uuid == None:
+            if uuid is None:
                 self.uuid = libbe.util.id.uuid_gen()
             self.time = int(time.time()) # only save to second precision
             self.in_reply_to = in_reply_to
@@ -254,7 +252,7 @@ class Comment (Tree, settings_object.SavedSettingsObject):
 
     def _setting_attr_string(self, setting):
         value = getattr(self, setting)
-        if value == None:
+        if value is None:
             return ""
         if type(value) not in (str,):
             return str(value)
@@ -268,7 +266,7 @@ class Comment (Tree, settings_object.SavedSettingsObject):
           * if that id matches another comments .alt_id, in which case
             return the matching comments .uuid.
         """
-        if self.in_reply_to == None:
+        if self.in_reply_to is None:
             return None
         else:
             try:
@@ -478,9 +476,9 @@ class Comment (Tree, settings_object.SavedSettingsObject):
             self.alt_id = None
         for estr in other.extra_strings:
             if not estr in self.extra_strings:
-                if accept_extra_strings == True:
+                if accept_extra_strings:
                     self.extra_strings.append(estr)
-                elif change_exception == True:
+                elif change_exception:
                     raise ValueError('Merge would add extra string "%s" to comment %s' \
                         % (estr, self.uuid))
 
@@ -492,7 +490,7 @@ class Comment (Tree, settings_object.SavedSettingsObject):
         >>> print comm.string(indent=2)
           --------- Comment ---------
           Name: //abc
-          From: 
+          From:
           Date: Thu, 01 Jan 1970 00:00:00 +0000
         <BLANKLINE>
           Some
@@ -544,50 +542,50 @@ class Comment (Tree, settings_object.SavedSettingsObject):
         >>> print a.string_thread(flatten=True)
         --------- Comment ---------
         Name: //a
-        From: 
+        From:
         Date: Thu, 20 Nov 2008 01:00:00 +0000
         <BLANKLINE>
         Insightful remarks
           --------- Comment ---------
           Name: //b
-          From: 
+          From:
           Date: Thu, 20 Nov 2008 02:00:00 +0000
         <BLANKLINE>
           Critique original comment
           --------- Comment ---------
           Name: //c
-          From: 
+          From:
           Date: Thu, 20 Nov 2008 03:00:00 +0000
         <BLANKLINE>
           Begin flamewar :p
         --------- Comment ---------
         Name: //d
-        From: 
+        From:
         Date: Thu, 20 Nov 2008 04:00:00 +0000
         <BLANKLINE>
         Useful examples
         >>> print a.string_thread()
         --------- Comment ---------
         Name: //a
-        From: 
+        From:
         Date: Thu, 20 Nov 2008 01:00:00 +0000
         <BLANKLINE>
         Insightful remarks
           --------- Comment ---------
           Name: //b
-          From: 
+          From:
           Date: Thu, 20 Nov 2008 02:00:00 +0000
         <BLANKLINE>
           Critique original comment
           --------- Comment ---------
           Name: //c
-          From: 
+          From:
           Date: Thu, 20 Nov 2008 03:00:00 +0000
         <BLANKLINE>
           Begin flamewar :p
         --------- Comment ---------
         Name: //d
-        From: 
+        From:
         Date: Thu, 20 Nov 2008 04:00:00 +0000
         <BLANKLINE>
         Useful examples
@@ -607,7 +605,7 @@ class Comment (Tree, settings_object.SavedSettingsObject):
     def load_settings(self, settings_mapfile=None):
         if self.uuid == INVALID_UUID:
             return
-        if settings_mapfile == None:
+        if settings_mapfile is None:
             settings_mapfile = self.storage.get(
                 self.id.storage('values'), '{}\n')
         try:
@@ -732,8 +730,8 @@ def cmp_attr(comment_1, comment_2, attr, invert=False):
         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 val_1 is None: val_1 = None
+    if val_2 is None: val_2 = None
 
     if invert == True :
         return -cmp(val_1, val_2)
@@ -767,5 +765,5 @@ class CommentCompoundComparator (object):
 
 cmp_full = CommentCompoundComparator()
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     suite = doctest.DocTestSuite()
diff --git a/libbe/diff.py b/libbe/diff.py
index c2f9c8e..fe83881 100644
--- a/libbe/diff.py
+++ b/libbe/diff.py
@@ -32,6 +32,12 @@ from libbe.storage.util.settings_object import setting_name_to_attr_name
 from libbe.util.utility import time_to_str
 
 
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
+
 class SubscriptionType (libbe.util.tree.Tree):
     """Trees of subscription types to allow users to select exactly what
     notifications they want to subscribe to.
@@ -132,7 +138,7 @@ def subscriptions_from_string(string=None, subscription_sep=',', id_sep=':'):
       ...
     ValueError: Invalid subscription "DIR::new", should be ID:TYPE
     """
-    if string == None:
+    if string is None:
         return [Subscription(BUGDIR_ID, BUGDIR_TYPE_ALL)]
     subscriptions = []
     for subscription in string.split(','):
@@ -196,7 +202,7 @@ class DiffTree (libbe.util.tree.Tree):
         self.masked = masked
     def paths(self, parent_path=None):
         paths = []
-        if parent_path == None:
+        if parent_path is None:
             path = self.name
         else:
             path = '%s/%s' % (parent_path, self.name)
@@ -225,16 +231,16 @@ class DiffTree (libbe.util.tree.Tree):
         raise KeyError('%s points to child not in %s' % (names, [c.name for c in self]))
     def report_string(self):
         report = self.report()
-        if report == None:
+        if report is None:
             return ''
         return '\n'.join(report)
     def report(self, root=None, parent=None, depth=0):
-        if root == None:
+        if root is None:
             root = self.make_root()
-        if self.masked == True:
+        if self.masked:
             return root
         data_part = self.data_part(depth)
-        if self.requires_children == True \
+        if self.requires_children \
                 and len([c for c in self if c.masked == False]) == 0:
             pass
         else:
@@ -250,12 +256,12 @@ class DiffTree (libbe.util.tree.Tree):
         if data_part != None:
             root.append(data_part)
     def data_part(self, depth, indent=True):
-        if self.data == None:
+        if self.data is 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:
+        if indent:
             data_part_lines = data_part.splitlines()
             indent = '  '*(depth)
             line_sep = '\n'+indent
@@ -574,11 +580,11 @@ class Diff (object):
         can pass in a DiffTree subclass via diff_tree to override the
         default report assembly process.
         """
-        if allow_cached == True \
+        if allow_cached \
                 and hasattr(self, '_cached_full_report') \
                 and diff_tree == self._cached_full_report_diff_tree:
             return self._sub_report(subscriptions)
-        if subscriptions == None:
+        if subscriptions is None:
             subscriptions = [Subscription(BUGDIR_ID, BUGDIR_TYPE_ALL)]
         bugdir_settings = sorted(self.new_bugdir.settings_properties)
         root = diff_tree('bugdir')
diff --git a/libbe/storage/base.py b/libbe/storage/base.py
index 4c05287..7020c10 100644
--- a/libbe/storage/base.py
+++ b/libbe/storage/base.py
@@ -23,7 +23,6 @@ Abstract bug repository data storage to easily support multiple backends.
 import copy
 import os
 import pickle
-import types
 
 from libbe.error import NotSupported
 import libbe.storage
@@ -32,7 +31,7 @@ from libbe.util import InvalidObject
 import libbe.version
 from libbe import TESTING
 
-if TESTING == True:
+if TESTING:
     import doctest
     import os.path
     import sys
@@ -40,12 +39,17 @@ if TESTING == True:
 
     from libbe.util.utility import Dir
 
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
 class ConnectionError (Exception):
     pass
 
 class InvalidStorageVersion(ConnectionError):
     def __init__(self, active_version, expected_version=None):
-        if expected_version == None:
+        if expected_version is None:
             expected_version = libbe.storage.STORAGE_VERSION
         msg = 'Storage in "%s" not the expected "%s"' \
             % (active_version, expected_version)
@@ -60,7 +64,7 @@ class InvalidID (KeyError):
         self.id = id
         self.revision = revision
     def __str__(self):
-        if self.msg == None:
+        if self.msg is None:
             return '%s in revision %s' % (self.id, self.revision)
         return self.msg
 
@@ -93,7 +97,7 @@ class _EMPTY (object):
 class Entry (Tree):
     def __init__(self, id, value=_EMPTY, parent=None, directory=False,
                  children=None):
-        if children == None:
+        if children is None:
             Tree.__init__(self)
         else:
             Tree.__init__(self, children)
@@ -114,14 +118,14 @@ class Entry (Tree):
         return str(self)
 
     def __cmp__(self, other, local=False):
-        if other == None:
+        if other is None:
             return cmp(1, None)
         if cmp(self.id, other.id) != 0:
             return cmp(self.id, other.id)
         if cmp(self.value, other.value) != 0:
             return cmp(self.value, other.value)
         if local == False:
-            if self.parent == None:
+            if self.parent is None:
                 if cmp(self.parent, other.parent) != 0:
                     return cmp(self.parent, other.parent)
             elif self.parent.__cmp__(other.parent, local=True) != 0:
@@ -250,7 +254,7 @@ class Storage (object):
             self._add(id, *args, **kwargs)
 
     def _add(self, id, parent=None, directory=False):
-        if parent == None:
+        if parent is None:
             parent = '__ROOT__'
         p = self._data[parent]
         self._data[id] = Entry(id, parent=p, directory=directory)
@@ -296,7 +300,7 @@ class Storage (object):
         return self._ancestors(*args, **kwargs)
 
     def _ancestors(self, id=None, revision=None):
-        if id == None:
+        if id is None:
             return []
         ancestors = []
         stack = [id]
@@ -316,7 +320,7 @@ class Storage (object):
         return self._children(*args, **kwargs)
 
     def _children(self, id=None, revision=None):
-        if id == None:
+        if id is None:
             id = '__ROOT__'
         return [c.id for c in self._data[id] if not c.id.startswith('__')]
 
@@ -362,7 +366,7 @@ class Storage (object):
     def _set(self, id, value):
         if id not in self._data:
             raise InvalidID(id)
-        if self._data[id].directory == True:
+        if self._data[id].directory:
             raise InvalidDirectory(
                 'Directory %s cannot have data' % self.parent)
         self._data[id].value = value
@@ -408,13 +412,13 @@ class VersionedStorage (Storage):
         self._data = None
 
     def _add(self, id, parent=None, directory=False):
-        if parent == None:
+        if parent is None:
             parent = '__ROOT__'
         p = self._data[-1][parent]
         self._data[-1][id] = Entry(id, parent=p, directory=directory)
 
     def _exists(self, id, revision=None):
-        if revision == None:
+        if revision is None:
             revision = -1
         else:
             revision = int(revision)
@@ -432,9 +436,9 @@ class VersionedStorage (Storage):
             self._remove(entry.id)
 
     def _ancestors(self, id=None, revision=None):
-        if id == None:
+        if id is None:
             return []
-        if revision == None:
+        if revision is None:
             revision = -1
         else:
             revision = int(revision)
@@ -450,9 +454,9 @@ class VersionedStorage (Storage):
         return ancestors
 
     def _children(self, id=None, revision=None):
-        if id == None:
+        if id is None:
             id = '__ROOT__'
-        if revision == None:
+        if revision is None:
             revision = -1
         else:
             revision = int(revision)
@@ -460,7 +464,7 @@ class VersionedStorage (Storage):
                 if not c.id.startswith('__')]
 
     def _get(self, id, default=InvalidObject, revision=None):
-        if revision == None:
+        if revision is None:
             revision = -1
         else:
             revision = int(revision)
@@ -508,7 +512,7 @@ class VersionedStorage (Storage):
 
         If the specified revision does not exist, raise InvalidRevision.
         """
-        if index == None:
+        if index is None:
             return None
         try:
             if int(index) != index:
@@ -518,7 +522,7 @@ class VersionedStorage (Storage):
         L = len(self._data) - 1  # -1 b/c of initial commit
         if index >= -L and index <= L:
             return str(index % L)
-        raise InvalidRevision(i)
+        raise InvalidRevision(index)
 
     def changed(self, revision):
         """Return a tuple of lists of ids `(new, modified, removed)` from the
@@ -540,7 +544,7 @@ class VersionedStorage (Storage):
         return (new, modified, removed)
 
 
-if TESTING == True:
+if TESTING:
     class StorageTestCase (unittest.TestCase):
         """Test cases for Storage class."""
 
diff --git a/libbe/storage/util/properties.py b/libbe/storage/util/properties.py
index 4aa3ce6..ad9d06c 100644
--- a/libbe/storage/util/properties.py
+++ b/libbe/storage/util/properties.py
@@ -42,10 +42,15 @@ import copy
 import types
 
 import libbe
-if libbe.TESTING == True:
+if libbe.TESTING:
     import unittest
 
 
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
 class ValueCheckError (ValueError):
     def __init__(self, name, value, allowed):
         action = "in" # some list of allowed values
@@ -103,7 +108,7 @@ def local_property(name, null=None, mutable_null=False):
         def _fget(self):
             if fget is not None:
                 fget(self)
-            if mutable_null == True:
+            if mutable_null:
                 ret_null = copy.deepcopy(null)
             else:
                 ret_null = null
@@ -203,7 +208,7 @@ def defaulting_property(default=None, null=None,
         def _fget(self):
             value = fget(self)
             if value == null:
-                if mutable_default == True:
+                if mutable_default:
                     return copy.deepcopy(default)
                 else:
                     return default
@@ -380,7 +385,7 @@ def change_hook_property(hook, mutable=False, default=None):
         fset = funcs.get("fset")
         name = funcs.get("name", "<unknown>")
         def _fget(self, new_value=None, from_fset=False): # only used if mutable == True
-            if from_fset == True:
+            if from_fset:
                 value = new_value # compare new value with cached
             else:
                 value = fget(self) # compare current value with cached
@@ -388,26 +393,26 @@ def change_hook_property(hook, mutable=False, default=None):
                 # there has been a change, cache new value
                 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
+                if from_fset: # return previously cached value
                     value = old_value
                 else: # the value changed while we weren't looking
                     hook(self, old_value, value)
             return value
         def _fset(self, value):
-            if mutable == True: # get cached previous value
+            if mutable: # get cached previous value
                 old_value = _fget(self, new_value=value, from_fset=True)
             else:
                 old_value = fget(self)
             fset(self, value)
             if value != old_value:
                 hook(self, old_value, value)
-        if mutable == True:
+        if mutable:
             funcs["fget"] = _fget
         funcs["fset"] = _fset
         return funcs
     return decorator
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     class DecoratorTests(unittest.TestCase):
         def testLocalDoc(self):
             class Test(object):
diff --git a/libbe/storage/vcs/base.py b/libbe/storage/vcs/base.py
index dfd007f..579935e 100644
--- a/libbe/storage/vcs/base.py
+++ b/libbe/storage/vcs/base.py
@@ -44,12 +44,18 @@ from libbe.util.subproc import CommandError, invoke
 from libbe.util.plugin import import_by_name
 import libbe.storage.util.upgrade as upgrade
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     import unittest
     import doctest
 
     import libbe.ui.util.user
 
+
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
 VCS_ORDER = ['bzr', 'darcs', 'git', 'hg', 'monotone']
 """List VCS modules in order of preference.
 
@@ -75,7 +81,7 @@ def _get_matching_vcs(matchfn):
     for submodname in VCS_ORDER:
         module = import_by_name('libbe.storage.vcs.%s' % submodname)
         vcs = module.new()
-        if matchfn(vcs) == True:
+        if matchfn(vcs):
             return vcs
     return VCS()
 
@@ -117,7 +123,7 @@ class VCSUnableToRoot (libbe.storage.base.ConnectionError):
 
 class InvalidPath (InvalidID):
     def __init__(self, path, root, msg=None, **kwargs):
-        if msg == None:
+        if msg is None:
             msg = 'Path "%s" not in root "%s"' % (path, root)
         InvalidID.__init__(self, msg=msg, **kwargs)
         self.path = path
@@ -132,7 +138,7 @@ class SpacerCollision (InvalidPath):
 
 class CachedPathID (object):
     """Cache Storage ID <-> path policy.
- 
+
     Paths generated following::
 
        .../.be/BUGDIR/bugs/BUG/comments/COMMENT
@@ -209,7 +215,7 @@ class CachedPathID (object):
 
             UUID\tPATH
         """
-        if cache == None:
+        if cache is None:
             self._cache = {}
         else:
             self._cache = cache
@@ -231,7 +237,7 @@ class CachedPathID (object):
                 pass
         if self._cache != cache:
             self._changed = True
-        if cache == None:
+        if cache is None:
             self.disconnect()
 
     def destroy(self):
@@ -253,7 +259,7 @@ class CachedPathID (object):
         f.close()
 
     def disconnect(self):
-        if self._changed == True:
+        if self._changed:
             f = codecs.open(self._cache_path, 'w', self.encoding)
             for uuid,path in list(self._cache.items()):
                 f.write('%s\t%s\n' % (uuid, path))
@@ -271,7 +277,7 @@ class CachedPathID (object):
             self.init(cache=self._cache)
             if uuid not in self._cache:
                 raise InvalidID(uuid)
-        if relpath == True:
+        if relpath:
             return os.path.join(self._cache[uuid], *extra)
         return os.path.join(self._root, self._cache[uuid], *extra)
 
@@ -285,7 +291,7 @@ class CachedPathID (object):
             # already added
             path = self.path(id)
         else:
-            if parent == None:
+            if parent is None:
                 parent_path = ''
                 spacer = self._spacer_dirs[0]
             else:
@@ -445,7 +451,7 @@ class VCS (libbe.storage.base.VersionedStorage):
     def _vcs_path(self, id, revision):
         """
         Return the relative path to object id as of revision.
-        
+
         Revision will not be None.
         """
         raise NotImplementedError
@@ -454,7 +460,7 @@ class VCS (libbe.storage.base.VersionedStorage):
         """
         Return True if path (as returned by _vcs_path) was a directory
         as of revision, False otherwise.
-        
+
         Revision will not be None.
         """
         raise NotImplementedError
@@ -463,7 +469,7 @@ class VCS (libbe.storage.base.VersionedStorage):
         """
         Return a list of the contents of the directory path (as
         returned by _vcs_path) as of revision.
-        
+
         Revision will not be None, and ._vcs_isdir(path, revision)
         will be True.
         """
@@ -610,7 +616,7 @@ class VCS (libbe.storage.base.VersionedStorage):
         """
         if not hasattr(self, 'user_id'):
             self.user_id = self._vcs_get_user_id()
-            if self.user_id == None:
+            if self.user_id is None:
                 # guess missing info
                 name = libbe.ui.util.user.get_fallback_fullname()
                 email = libbe.ui.util.user.get_fallback_email()
@@ -696,13 +702,13 @@ class VCS (libbe.storage.base.VersionedStorage):
         self._cached_path_id.disconnect()
 
     def path(self, id, revision=None, relpath=True):
-        if revision == None:
+        if revision is None:
             path = self._cached_path_id.path(id)
-            if relpath == True:
+            if relpath:
                 return self._u_rel_path(path)
             return path
         path = self._vcs_path(id, revision)
-        if relpath == True:
+        if relpath:
             return path
         return os.path.join(self.repo, path)
 
@@ -729,7 +735,7 @@ class VCS (libbe.storage.base.VersionedStorage):
         self._add_path(path, **kwargs)
 
     def _exists(self, id, revision=None):
-        if revision == None:
+        if revision is None:
             try:
                 path = self.path(id, revision, relpath=False)
             except InvalidID as e:
@@ -781,11 +787,11 @@ class VCS (libbe.storage.base.VersionedStorage):
                 id = self._u_path_to_id(path)
                 ancestors.append(id)
             except (SpacerCollision, InvalidPath):
-                pass    
+                pass
         return ancestors
 
     def _children(self, id=None, revision=None):
-        if revision == None:
+        if revision is None:
             isdir = os.path.isdir
             listdir = os.listdir
         else:
@@ -797,7 +803,7 @@ class VCS (libbe.storage.base.VersionedStorage):
             path = self.be_dir
         else:
             path = self.path(id, revision, relpath=False)
-        if isdir(path) == False: 
+        if isdir(path) == False:
             return []
         children = listdir(path)
         for i,c in enumerate(children):
@@ -809,7 +815,7 @@ class VCS (libbe.storage.base.VersionedStorage):
                 children[i] = None
                 children[i] = None
         for i,c in enumerate(children):
-            if c == None: continue
+            if c is None: continue
             cpath = os.path.join(path, c)
             children[i] = self._u_path_to_id(cpath)
         return [c for c in children if c != None]
@@ -861,7 +867,7 @@ class VCS (libbe.storage.base.VersionedStorage):
         return revision
 
     def revision_id(self, index=None):
-        if index == None:
+        if index is None:
             return None
         try:
             if int(index) != index:
@@ -869,7 +875,7 @@ class VCS (libbe.storage.base.VersionedStorage):
         except ValueError:
             raise InvalidRevision(index)
         revid = self._vcs_revision_id(index)
-        if revid == None:
+        if revid is None:
             raise libbe.storage.base.InvalidRevision(index)
         return revid
 
@@ -930,7 +936,7 @@ class VCS (libbe.storage.base.VersionedStorage):
     def _u_find_id_from_manifest(self, id, manifest, revision=None):
         """Search for the relative path to id using manifest, a list of all
         files.
-        
+
         Returns None if the id is not found.
         """
         be_dir = self._cached_path_id._spacer_dirs[0]
@@ -991,8 +997,8 @@ class VCS (libbe.storage.base.VersionedStorage):
         >>> vcs._u_rel_path("./a", ".")
         'a'
         """
-        if root == None:
-            if self.repo == None:
+        if root is None:
+            if self.repo is None:
                 raise VCSNotRooted(self)
             root = self.repo
         path = os.path.abspath(path)
@@ -1015,7 +1021,7 @@ class VCS (libbe.storage.base.VersionedStorage):
         >>> vcs._u_abspath(".be", "/a.b/c")
         '/a.b/c/.be'
         """
-        if root == None:
+        if root is None:
             assert self.repo != None, "VCS not rooted"
             root = self.repo
         return os.path.abspath(os.path.join(root, path))
@@ -1045,11 +1051,11 @@ class VCS (libbe.storage.base.VersionedStorage):
         --------
         libbe.storage.util.upgrade
         """
-        if path == None:
+        if path is None:
             path = os.path.join(self.repo, '.be', 'version')
         if not os.path.exists(path):
             raise libbe.storage.InvalidStorageVersion(None)
-        if revision == None: # don't require connection
+        if revision is None: # don't require connection
             return libbe.util.encoding.get_file_contents(
                 path, decode=True).rstrip()
         relpath = self._u_rel_path(path)
@@ -1070,7 +1076,7 @@ class VCS (libbe.storage.base.VersionedStorage):
             self._vcs_add(self._u_rel_path(path))
 
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     class VCSTestCase (unittest.TestCase):
         """
         Test cases for base VCS class (in addition to the Storage test
@@ -1089,13 +1095,13 @@ if libbe.TESTING == True:
             self.dir = Dir()
             self.dirname = self.dir.path
             self.s = self.Class(repo=self.dirname)
-            if self.s.installed() == True:
+            if self.s.installed():
                 self.s.init()
                 self.s.connect()
 
         def tearDown(self):
             super(VCSTestCase, self).tearDown()
-            if self.s.installed() == True:
+            if self.s.installed():
                 self.s.disconnect()
                 self.s.destroy()
             self.dir.cleanup()
@@ -1147,7 +1153,7 @@ if libbe.TESTING == True:
             """Should get the existing user ID."""
             if self.s.installed():
                 user_id = self.s.get_user_id()
-                if user_id == None:
+                if user_id is None:
                     return
                 name,email = libbe.ui.util.user.parse_user_id(user_id)
                 if email != None:
@@ -1156,7 +1162,7 @@ if libbe.TESTING == True:
     def make_vcs_testcase_subclasses(vcs_class, namespace):
         c = vcs_class()
         if c.installed():
-            if c.versioned == True:
+            if c.versioned:
                 libbe.storage.base.make_versioned_storage_testcase_subclasses(
                     vcs_class, namespace)
             else:
diff --git a/libbe/storage/vcs/darcs.py b/libbe/storage/vcs/darcs.py
index 41262f5..5ec9a26 100644
--- a/libbe/storage/vcs/darcs.py
+++ b/libbe/storage/vcs/darcs.py
@@ -39,11 +39,17 @@ import libbe
 from ...util.subproc import CommandError
 from . import base
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     import doctest
     import unittest
 
 
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
+
 def new():
     return Darcs()
 
@@ -98,7 +104,7 @@ class Darcs(base.VCS):
         NotImplementedError: Cannot parse non-integer portion "0pre2" of Darcs version "2.0.0pre2"
         """
         if not hasattr(self, '_parsed_version') \
-                or self._parsed_version == None:
+                or self._parsed_version is None:
             num_part = self.version().split(' ')[0]
             self._parsed_version = []
             for num in num_part.split('.'):
@@ -119,12 +125,12 @@ class Darcs(base.VCS):
     def _vcs_get_user_id(self):
         # following http://darcs.net/manual/node4.html#SECTION00410030000000000000
         # as of June 22th, 2010
-        if self.repo == None:
+        if self.repo is None:
             return None
         for pref_file in ['author', 'email']:
             for prefs_dir in [os.path.join(self.repo, '_darcs', 'prefs'),
                               os.path.expanduser(os.path.join('~', '.darcs'))]:
-                if prefs_dir == None:
+                if prefs_dir is None:
                     continue
                 pref_path = os.path.join(prefs_dir, pref_file)
                 if os.path.exists(pref_path):
@@ -135,7 +141,7 @@ class Darcs(base.VCS):
         return None
 
     def _vcs_detect(self, path):
-        if self._u_search_parent_directories(path, "_darcs") != None :
+        if self._u_search_parent_directories(path, "_darcs") is not None :
             return True
         return False
 
@@ -146,7 +152,7 @@ class Darcs(base.VCS):
         if os.path.isdir(path) != True:
             path = os.path.dirname(path)
         darcs_dir = self._u_search_parent_directories(path, '_darcs')
-        if darcs_dir == None:
+        if darcs_dir is None:
             return None
         return os.path.dirname(darcs_dir)
 
@@ -175,7 +181,7 @@ class Darcs(base.VCS):
         pass # darcs notices changes
 
     def _vcs_get_file_contents(self, path, revision=None):
-        if revision == None:
+        if revision is None:
             return base.VCS._vcs_get_file_contents(self, path, revision)
         if self.version_cmp(2, 0, 0) == 1:
             status,output,error = self._u_invoke_client( \
@@ -266,7 +272,7 @@ class Darcs(base.VCS):
         else:
             revline = re.compile("Finished recording patch '(.*)'")
             match = revline.search(output)
-            assert match != None, output+error
+            assert match is not None, output+error
             assert len(match.groups()) == 1
             revision = match.groups()[0]
         return revision
@@ -308,7 +314,7 @@ class Darcs(base.VCS):
         if i+1 < len(revisions):
             next_rev = revisions[i+1]
             args.extend(['--from-patch', next_rev])
-        if path != None:
+        if path is not None:
             args.append(path)
         kwargs = {'unicode_output':unicode_output}
         status,output,error = self._u_invoke_client(
@@ -356,7 +362,7 @@ class Darcs(base.VCS):
           @@ -1 +0,0 @@
           -this entry will be deleted
           \ No newline at end of file
-          
+
         """
         new = []
         modified = []
@@ -404,7 +410,7 @@ class Darcs(base.VCS):
         return self._parse_diff(self._diff(revision))
 
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     base.make_vcs_testcase_subclasses(Darcs, sys.modules[__name__])
 
     unitsuite =unittest.TestLoader().loadTestsFromModule(sys.modules[__name__])
diff --git a/libbe/storage/vcs/monotone.py b/libbe/storage/vcs/monotone.py
index abd3142..add7be9 100644
--- a/libbe/storage/vcs/monotone.py
+++ b/libbe/storage/vcs/monotone.py
@@ -38,6 +38,11 @@ if libbe.TESTING == True:
     import sys
 
 
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
 def new():
     return Monotone()
 
@@ -315,15 +320,15 @@ class Monotone (base.VCS):
           # old_revision [1ce9ac2cfe3166b8ad23a60555f8a70f37686c25]
           #
           # delete ".be/dir/bugs/moved"
-          # 
+          #
           # delete ".be/dir/bugs/removed"
-          # 
+          #
           # add_file ".be/dir/bugs/moved2"
           #  content [33e4510df9abef16dad7c65c0775e74602cc5005]
-          # 
+          #
           # add_file ".be/dir/bugs/new"
           #  content [45c45b5630f7446f83b0e14ee1525e449a06131c]
-          # 
+          #
           # patch ".be/dir/bugs/modified"
           #  from [809bf3b80423c361849386008a0ce01199d30929]
           #    to [f13d3ec08972e2b41afecd9a90d4bc71cdcea338]
diff --git a/libbe/util/tree.py b/libbe/util/tree.py
index c6aa46b..5d0da49 100644
--- a/libbe/util/tree.py
+++ b/libbe/util/tree.py
@@ -22,9 +22,10 @@
 """
 
 import libbe
-if libbe.TESTING == True:
+if libbe.TESTING:
     import doctest
 
+
 class Tree(list):
     """A traversable tree structure.
 
@@ -115,7 +116,7 @@ class Tree(list):
     True
     """
     def __cmp__(self, other):
-        return cmp(id(self), id(other))
+        return (id(self) > id(other)) - (id(self) < id(other))
 
     def __eq__(self, other):
         return self.__cmp__(other) == 0
@@ -172,7 +173,7 @@ class Tree(list):
           in the order they are stored, so you might want to
           :py:meth:`sort` your tree first.
         """
-        if depth_first == True:
+        if depth_first:
             yield self
             for child in self:
                 for descendant in child.traverse():
@@ -213,7 +214,7 @@ class Tree(list):
 
         """
         stack = [] # ancestry of the current node
-        if flatten == True:
+        if flatten:
             depthDict = {}
 
         for node in self.traverse(depth_first=True):
@@ -256,5 +257,5 @@ class Tree(list):
                 return True
         return False
 
-if libbe.TESTING == True:
+if libbe.TESTING:
     suite = doctest.DocTestSuite()
diff --git a/libbe/util/wsgi.py b/libbe/util/wsgi.py
index 96ddf60..46e1b3c 100644
--- a/libbe/util/wsgi.py
+++ b/libbe/util/wsgi.py
@@ -36,7 +36,6 @@ import io
 import sys
 import time
 import traceback
-import types
 import urllib.request, urllib.parse, urllib.error
 import urllib.parse
 import wsgiref.simple_server
@@ -67,7 +66,12 @@ import libbe.util.http
 import libbe.util.id
 
 
-if libbe.TESTING == True:
+# https://stackoverflow.com/a/56719588/164233
+def cmp(a, b):
+    return (int(a) > int(b)) - (int(a) < int(b))
+
+
+if libbe.TESTING:
     import doctest
     import unittest
     import wsgiref.validate
@@ -627,7 +631,7 @@ class ServerCommand (libbe.command.base.Command):
                 'PID file {} already exists'.format(params['pidfile']))
         pid = os.getpid()
         with open(params['pidfile'], 'w') as f:  # race between exist and open
-            f.write(str(os.getpid()))            
+            f.write(str(os.getpid()))
         self.logger.log(
             self.log_level, 'Got PID file as {}'.format(pid))
 
@@ -935,12 +939,12 @@ def _make_certs(server_name, logger=None, level=None):
 
     `mk_certs(server_name) -> (pkey_filename, cert_filename)`
     """
-    if OpenSSL == None:
+    if OpenSSL is None:
         raise libbe.command.UserError(
             'SSL certificate generation requires the OpenSSL module')
     pkey_file,cert_file = _get_cert_filenames(
         server_name, autogenerate=False)
-    if logger != None:
+    if logger is not None:
         logger.log(
             level, 'Generating certificates {} {}'.format(
                 pkey_file, cert_file))