REF/TYP: define Index methods non-dynamically (pandas-dev#37038)

Author: jbrockmendel

pandas/core/indexes/base.py

@@ -5418,29 +5418,23 @@ def _arith_method(self, other, op):
             return (Index(result[0]), Index(result[1]))
         return Index(result)
 
-    @classmethod
-    def _add_numeric_methods_unary(cls):
-        """
-        Add in numeric unary methods.
-        """
+    def _unary_method(self, op):
+        result = op(self._values)
+        return Index(result, name=self.name)
 
-        def _make_evaluate_unary(op, opstr: str_t):
-            def _evaluate_numeric_unary(self):
+    def __abs__(self):
+        return self._unary_method(operator.abs)
 
-                attrs = self._get_attributes_dict()
-                return Index(op(self.values), **attrs)
+    def __neg__(self):
+        return self._unary_method(operator.neg)
 
-            _evaluate_numeric_unary.__name__ = opstr
-            return _evaluate_numeric_unary
+    def __pos__(self):
+        return self._unary_method(operator.pos)
 
-        setattr(cls, "__neg__", _make_evaluate_unary(operator.neg, "__neg__"))
-        setattr(cls, "__pos__", _make_evaluate_unary(operator.pos, "__pos__"))
-        setattr(cls, "__abs__", _make_evaluate_unary(np.abs, "__abs__"))
-        setattr(cls, "__inv__", _make_evaluate_unary(lambda x: -x, "__inv__"))
-
-    @classmethod
-    def _add_numeric_methods(cls):
-        cls._add_numeric_methods_unary()
+    def __inv__(self):
+        # TODO: why not operator.inv?
+        # TODO: __inv__ vs __invert__?
+        return self._unary_method(lambda x: -x)
 
     def any(self, *args, **kwargs):
         """
@@ -5565,9 +5559,6 @@ def shape(self):
         return self._values.shape
 
 
-Index._add_numeric_methods()
-
-
 def ensure_index_from_sequences(sequences, names=None):
     """
     Construct an index from sequences of data.

pandas/core/indexes/multi.py

@@ -3688,43 +3688,32 @@ def isin(self, values, level=None):
                 return np.zeros(len(levs), dtype=np.bool_)
             return levs.isin(values)
 
-    @classmethod
-    def _add_numeric_methods_add_sub_disabled(cls):
-        """
-        Add in the numeric add/sub methods to disable.
-        """
-        cls.__add__ = make_invalid_op("__add__")
-        cls.__radd__ = make_invalid_op("__radd__")
-        cls.__iadd__ = make_invalid_op("__iadd__")
-        cls.__sub__ = make_invalid_op("__sub__")
-        cls.__rsub__ = make_invalid_op("__rsub__")
-        cls.__isub__ = make_invalid_op("__isub__")
-
-    @classmethod
-    def _add_numeric_methods_disabled(cls):
-        """
-        Add in numeric methods to disable other than add/sub.
-        """
-        cls.__pow__ = make_invalid_op("__pow__")
-        cls.__rpow__ = make_invalid_op("__rpow__")
-        cls.__mul__ = make_invalid_op("__mul__")
-        cls.__rmul__ = make_invalid_op("__rmul__")
-        cls.__floordiv__ = make_invalid_op("__floordiv__")
-        cls.__rfloordiv__ = make_invalid_op("__rfloordiv__")
-        cls.__truediv__ = make_invalid_op("__truediv__")
-        cls.__rtruediv__ = make_invalid_op("__rtruediv__")
-        cls.__mod__ = make_invalid_op("__mod__")
-        cls.__rmod__ = make_invalid_op("__rmod__")
-        cls.__divmod__ = make_invalid_op("__divmod__")
-        cls.__rdivmod__ = make_invalid_op("__rdivmod__")
-        cls.__neg__ = make_invalid_op("__neg__")
-        cls.__pos__ = make_invalid_op("__pos__")
-        cls.__abs__ = make_invalid_op("__abs__")
-        cls.__inv__ = make_invalid_op("__inv__")
-
-
-MultiIndex._add_numeric_methods_disabled()
-MultiIndex._add_numeric_methods_add_sub_disabled()
+    # ---------------------------------------------------------------
+    # Arithmetic/Numeric Methods - Disabled
+
+    __add__ = make_invalid_op("__add__")
+    __radd__ = make_invalid_op("__radd__")
+    __iadd__ = make_invalid_op("__iadd__")
+    __sub__ = make_invalid_op("__sub__")
+    __rsub__ = make_invalid_op("__rsub__")
+    __isub__ = make_invalid_op("__isub__")
+    __pow__ = make_invalid_op("__pow__")
+    __rpow__ = make_invalid_op("__rpow__")
+    __mul__ = make_invalid_op("__mul__")
+    __rmul__ = make_invalid_op("__rmul__")
+    __floordiv__ = make_invalid_op("__floordiv__")
+    __rfloordiv__ = make_invalid_op("__rfloordiv__")
+    __truediv__ = make_invalid_op("__truediv__")
+    __rtruediv__ = make_invalid_op("__rtruediv__")
+    __mod__ = make_invalid_op("__mod__")
+    __rmod__ = make_invalid_op("__rmod__")
+    __divmod__ = make_invalid_op("__divmod__")
+    __rdivmod__ = make_invalid_op("__rdivmod__")
+    # Unary methods disabled
+    __neg__ = make_invalid_op("__neg__")
+    __pos__ = make_invalid_op("__pos__")
+    __abs__ = make_invalid_op("__abs__")
+    __inv__ = make_invalid_op("__inv__")
 
 
 def sparsify_labels(label_list, start: int = 0, sentinel=""):

pandas/core/indexes/numeric.py

@@ -275,8 +275,6 @@ def _can_union_without_object_cast(self, other) -> bool:
         return other.dtype == "f8" or other.dtype == self.dtype
 
 
-Int64Index._add_numeric_methods()
-
 _uint64_descr_args = dict(
     klass="UInt64Index", ltype="unsigned integer", dtype="uint64", extra=""
 )
@@ -321,8 +319,6 @@ def _can_union_without_object_cast(self, other) -> bool:
         return other.dtype == "f8" or other.dtype == self.dtype
 
 
-UInt64Index._add_numeric_methods()
-
 _float64_descr_args = dict(
     klass="Float64Index", dtype="float64", ltype="float", extra=""
 )
@@ -425,6 +421,3 @@ def isin(self, values, level=None):
     def _can_union_without_object_cast(self, other) -> bool:
         # See GH#26778, further casting may occur in NumericIndex._union
         return is_numeric_dtype(other.dtype)
-
-
-Float64Index._add_numeric_methods()