remove blist sortedset as soft dependency

PYTHON-385

cassandra/util.py

@@ -485,24 +485,18 @@ class WeakSet(object):
     def isdisjoint(self, other):
         return len(self.intersection(other)) == 0
 
-try:
-    from blist import sortedset
-except ImportError:
 
 from bisect import bisect_left
 
-    class sortedset(object):
+
+class SortedSet(object):
     '''
     A sorted set based on sorted list
 
-        This set is used in place of blist.sortedset in Python environments
-        where blist module/extension is not available.
-
     A sorted set implementation is used in this case because it does not
     require its elements to be immutable/hashable.
 
     #Not implemented: update functions, inplace operators
-
     '''
 
     def __init__(self, iterable=()):
@@ -533,19 +527,19 @@ except ImportError:
         if isinstance(other, self.__class__):
             return self._items == other._items
         else:
-                if not isinstance(other, set):
-                    return False
-
-                return len(other) == len(self._items) and all(item in other for item in self._items)
+            try:
+                return len(other) == len(self._items) and all(item in self for item in other)
+            except TypeError:
+                return NotImplemented
 
     def __ne__(self, other):
         if isinstance(other, self.__class__):
             return self._items != other._items
         else:
-                if not isinstance(other, set):
-                    return True
-
-                return len(other) != len(self._items) or any(item not in other for item in self._items)
+            try:
+                return len(other) != len(self._items) or any(item not in self for item in other)
+            except TypeError:
+                return NotImplemented
 
     def __le__(self, other):
         return self.issubset(other)
@@ -561,20 +555,52 @@ except ImportError:
 
     def __and__(self, other):
         return self._intersect(other)
+    __rand__ = __and__
+
+    def __iand__(self, other):
+        isect = self._intersect(other)
+        self._items = isect._items
+        return self
 
     def __or__(self, other):
         return self.union(other)
+    __ror__ = __or__
+
+    def __ior__(self, other):
+        union = self.union(other)
+        self._items = union._items
+        return self
 
     def __sub__(self, other):
         return self._diff(other)
 
+    def __rsub__(self, other):
+        return sortedset(other) - self
+
+    def __isub__(self, other):
+        diff = self._diff(other)
+        self._items = diff._items
+        return self
+
     def __xor__(self, other):
         return self.symmetric_difference(other)
+    __rxor__ = __xor__
+
+    def __ixor__(self, other):
+        sym_diff = self.symmetric_difference(other)
+        self._items = sym_diff._items
+        return self
 
     def __contains__(self, item):
         i = bisect_left(self._items, item)
         return i < len(self._items) and self._items[i] == item
 
+    def __delitem__(self, i):
+        del self._items[i]
+
+    def __delslice__(self, i, j):
+        del self._items[i:j]
+
     def add(self, item):
         i = bisect_left(self._items, item)
         if i < len(self._items):
@@ -690,6 +716,8 @@ except ImportError:
                     isect.add(item)
         return isect
 
+sortedset = SortedSet  # backwards-compatibility
+
 
 from collections import Mapping
 from six.moves import cPickle

tox.ini

@@ -9,7 +9,6 @@ deps = nose
 
 [testenv]
 deps = {[base]deps}
-       py{26,27,33,34}: blist
        cython
        py26: unittest2
        py{26,27}: gevent