--- a/contrib/check-code.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/contrib/check-code.py	Mon Mar 13 12:40:14 2017 -0700
@@ -318,7 +318,7 @@
      'legacy exception syntax; use "as" instead of ","'),
     (r':\n(    )*( ){1,3}[^ ]', "must indent 4 spaces"),
     (r'release\(.*wlock, .*lock\)', "wrong lock release order"),
-    (r'\b__bool__\b', "__bool__ should be __nonzero__ in Python 2"),
+    (r'\bdef\s+__bool__\b', "__bool__ should be __nonzero__ in Python 2"),
     (r'os\.path\.join\(.*, *(""|\'\')\)',
      "use pathutil.normasprefix(path) instead of os.path.join(path, '')"),
     (r'\s0[0-7]+\b', 'legacy octal syntax; use "0o" prefix instead of "0"'),

--- a/contrib/perf.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/contrib/perf.py	Mon Mar 13 12:40:14 2017 -0700
@@ -165,6 +165,7 @@
                     self.hexfunc = node.short
             def __nonzero__(self):
                 return False
+            __bool__ = __nonzero__
             def startitem(self):
                 pass
             def data(self, **data):

--- a/mercurial/ancestor.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/ancestor.py	Mon Mar 13 12:40:14 2017 -0700
@@ -296,6 +296,8 @@
         except StopIteration:
             return False
 
+    __bool__ = __nonzero__
+
     def __iter__(self):
         """Generate the ancestors of _initrevs in reverse topological order.
 

--- a/mercurial/bundle2.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/bundle2.py	Mon Mar 13 12:40:14 2017 -0700
@@ -271,6 +271,8 @@
     def __nonzero__(self):
         return bool(self._sequences)
 
+    __bool__ = __nonzero__
+
 class bundleoperation(object):
     """an object that represents a single bundling process
 

--- a/mercurial/context.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/context.py	Mon Mar 13 12:40:14 2017 -0700
@@ -534,6 +534,8 @@
     def __nonzero__(self):
         return self._rev != nullrev
 
+    __bool__ = __nonzero__
+
     @propertycache
     def _changeset(self):
         return self._repo.changelog.changelogrevision(self.rev())
@@ -722,6 +724,8 @@
             # file is missing
             return False
 
+    __bool__ = __nonzero__
+
     def __str__(self):
         try:
             return "%s@%s" % (self.path(), self._changectx)
@@ -1238,6 +1242,8 @@
     def __nonzero__(self):
         return True
 
+    __bool__ = __nonzero__
+
     def _buildflagfunc(self):
         # Create a fallback function for getting file flags when the
         # filesystem doesn't support them
@@ -1711,6 +1717,8 @@
     def __nonzero__(self):
         return True
 
+    __bool__ = __nonzero__
+
     def linkrev(self):
         # linked to self._changectx no matter if file is modified or not
         return self.rev()

--- a/mercurial/hgweb/webutil.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/hgweb/webutil.py	Mon Mar 13 12:40:14 2017 -0700
@@ -72,6 +72,8 @@
         """return True if any revision to navigate over"""
         return self._first() is not None
 
+    __bool__ = __nonzero__
+
     def _first(self):
         """return the minimum non-filtered changeset or None"""
         try:

--- a/mercurial/localrepo.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/localrepo.py	Mon Mar 13 12:40:14 2017 -0700
@@ -585,6 +585,8 @@
     def __nonzero__(self):
         return True
 
+    __bool__ = __nonzero__
+
     def __len__(self):
         return len(self.changelog)
 

--- a/mercurial/manifest.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/manifest.py	Mon Mar 13 12:40:14 2017 -0700
@@ -431,6 +431,8 @@
         # makes it easier for extensions to override.
         return len(self._lm) != 0
 
+    __bool__ = __nonzero__
+
     def __setitem__(self, key, node):
         self._lm[key] = node, self.flags(key, '')
 

--- a/mercurial/obsolete.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/obsolete.py	Mon Mar 13 12:40:14 2017 -0700
@@ -552,6 +552,8 @@
                 pass
         return bool(self._all)
 
+    __bool__ = __nonzero__
+
     @property
     def readonly(self):
         """True if marker creation is disabled

--- a/mercurial/smartset.py	Mon Mar 13 21:58:43 2017 -0700
+++ b/mercurial/smartset.py	Mon Mar 13 12:40:14 2017 -0700
@@ -40,6 +40,8 @@
         """True if the smartset is not empty"""
         raise NotImplementedError()
 
+    __bool__ = __nonzero__
+
     def __contains__(self, rev):
         """provide fast membership testing"""
         raise NotImplementedError()
@@ -267,6 +269,8 @@
     def __nonzero__(self):
         return bool(len(self))
 
+    __bool__ = __nonzero__
+
     def sort(self, reverse=False):
         self._ascending = not bool(reverse)
         self._istopo = False
@@ -420,6 +424,8 @@
             return True
         return False
 
+    __bool__ = __nonzero__
+
     def __len__(self):
         # Basic implementation to be changed in future patches.
         # until this gets improved, we use generator expression
@@ -592,6 +598,8 @@
     def __nonzero__(self):
         return bool(self._r1) or bool(self._r2)
 
+    __bool__ = __nonzero__
+
     @util.propertycache
     def _list(self):
         if not self._genlist:
@@ -752,6 +760,8 @@
             return True
         return False
 
+    __bool__ = __nonzero__
+
     def __contains__(self, x):
         if x in self._cache:
             return self._cache[x]
@@ -970,6 +980,8 @@
             return True
         return False
 
+    __bool__ = __nonzero__
+
     def __len__(self):
         if not self._hiddenrevs:
             return abs(self._end - self._start)