Fix errors when a kwarg is named "col" (#35)

Author: hukkinj1

immutables/map.py

@@ -433,7 +433,17 @@ def __iter__(self):
 
 class Map:
 
-    def __init__(self, col=None, **kw):
+    def __init__(self, *args, **kw):
+        if not args:
+            col = None
+        elif len(args) == 1:
+            col = args[0]
+        else:
+            raise TypeError(
+                "immutables.Map expected at most 1 arguments, "
+                "got {}".format(len(args))
+            )
+
         self.__count = 0
         self.__root = BitmapNode(0, 0, [], 0)
         self.__hash = -1
@@ -483,8 +493,18 @@ def __eq__(self, other):
 
         return True
 
-    def update(self, col=None, **kw):
+    def update(self, *args, **kw):
+        if not args:
+            col = None
+        elif len(args) == 1:
+            col = args[0]
+        else:
+            raise TypeError(
+                "update expected at most 1 arguments, got {}".format(len(args))
+            )
+
         it = None
+
         if col is not None:
             if hasattr(col, 'items'):
                 it = iter(col.items())
@@ -721,7 +741,16 @@ def __contains__(self, key):
         else:
             return True
 
-    def update(self, col=None, **kw):
+    def update(self, *args, **kw):
+        if not args:
+            col = None
+        elif len(args) == 1:
+            col = args[0]
+        else:
+            raise TypeError(
+                "update expected at most 1 arguments, got {}".format(len(args))
+            )
+
         if self.__mutid == 0:
             raise ValueError('mutation {!r} has been finished'.format(self))
 

tests/test_map.py

@@ -1436,6 +1436,11 @@ def test_map_pickle(self):
     def test_map_is_subscriptable(self):
         self.assertIs(self.Map[int, str], self.Map)
 
+    def test_kwarg_named_col(self):
+        self.assertEqual(dict(self.Map(col=0)), {"col": 0})
+        self.assertEqual(dict(self.Map(a=0, col=1)), {"a": 0, "col": 1})
+        self.assertEqual(dict(self.Map({"a": 0}, col=1)), {"a": 0, "col": 1})
+
 
 class PyMapTest(BaseMapTest, unittest.TestCase):