Issue #9137: Fix issue in MutableMapping.update, which incorrectly

treated keyword arguments called 'self' or 'other' specially.

1 files changed, 9 insertions, 1 deletions

diff --git a/Lib/_abcoll.py b/Lib/_abcoll.py
index e9f06a5..cc00fd9 100644
--- a/Lib/_abcoll.py
+++ b/Lib/_abcoll.py
@@ -480,7 +480,15 @@ class MutableMapping(Mapping):
         except KeyError:
             pass
 
-    def update(self, other=(), **kwds):
+    def update(*args, **kwds):
+        if len(args) > 2:
+            raise TypeError("update() takes at most 2 positional "
+                            "arguments ({} given)".format(len(args)))
+        elif not args:
+            raise TypeError("update() takes at least 1 argument (0 given)")
+        self = args[0]
+        other = args[1] if len(args) >= 2 else ()
+
         if isinstance(other, Mapping):
             for key in other:
                 self[key] = other[key]