delegate '__nonzero__' to '__bool__' for py2/py3 compatibility in one…

… source. #1350

sphinx/ext/autodoc.py

@@ -54,9 +54,10 @@ def __getitem__(self, key):
             return dict.__getitem__(self, key)
         except KeyError:
             return self.default
-    def __nonzero__(self):
+    def __bool__(self):
         # docutils check "if option_spec"
         return True
+    __nonzero__ = __bool__  # for python2 compatibility
 
 identity = lambda x: x
 

sphinx/locale/__init__.py

@@ -60,8 +60,9 @@ def encode(self, encoding=None, errors=None):
     def __contains__(self, key):
         return key in self.data
 
-    def __nonzero__(self):
+    def __bool__(self):
         return bool(self.data)
+    __nonzero__ = __bool__  # for python2 compatibility
 
     def __dir__(self):
         return dir(text_type)

tests/etree13/ElementTree.py

@@ -246,14 +246,15 @@ def makeelement(self, tag, attrib):
     def __len__(self):
         return len(self._children)
 
-    def __nonzero__(self):
+    def __bool__(self):
         import warnings
         warnings.warn(
             "The behavior of this method will change in future versions. "
             "Use specific 'len(elem)' or 'elem is not None' test instead.",
             FutureWarning
             )
         return len(self._children) != 0 # emulate old behaviour
+    __nonzero__ = __bool__  # for python2 compatibility
 
     ##
     # Returns the given subelement.