conversion of cmp() function

1 files changed, 25 insertions, 21 deletions

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."""