add operators for Index

pandas-stubs/core/arraylike.pyi

@@ -7,6 +7,9 @@ from pandas import DataFrame
 
 class OpsMixinProtocol(Protocol): ...
 
+# We would like to use ->Self here so this could be used by Index, but mypy 0.991
+# doesn't support Self.  So we will have to add these operators directly to Index
+
 class OpsMixin:
     def __eq__(self: OpsMixinProtocol, other: object) -> DataFrame: ...  # type: ignore[override]
     def __ne__(self: OpsMixinProtocol, other: object) -> DataFrame: ...  # type: ignore[override]

pandas-stubs/core/indexes/base.pyi

@@ -146,14 +146,20 @@ class Index(IndexOpsMixin, PandasObject):
     def duplicated(
         self, keep: Literal["first", "last", False] = ...
     ) -> np_ndarray_bool: ...
-    def __add__(self, other) -> Index: ...
-    def __radd__(self, other) -> Index: ...
-    def __iadd__(self, other) -> Index: ...
-    def __sub__(self, other) -> Index: ...
-    def __rsub__(self, other) -> Index: ...
-    def __and__(self, other) -> Index: ...
-    def __or__(self, other) -> Index: ...
-    def __xor__(self, other) -> Index: ...
+    def __add__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __radd__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __sub__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __rsub__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __mul__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __rmul__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __truediv__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __rtruediv__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __floordiv__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __rfloordiv__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __pow__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __rpow__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __mod__(self: IndexT, other: Index | Scalar) -> IndexT: ...
+    def __rmod__(self: IndexT, other: Index | Scalar) -> IndexT: ...
     def __neg__(self: IndexT) -> IndexT: ...
     def __nonzero__(self) -> None: ...
     __bool__ = ...

pandas-stubs/core/indexes/numeric.pyi

@@ -9,16 +9,16 @@ class NumericIndex(Index):
     @property
     def is_all_dates(self) -> bool: ...
     def insert(self, loc, item): ...
-    def __add__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __radd__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __sub__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __rsub__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __mul__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __rmul__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __truediv__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __rtruediv__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __floordiv__(self, other: NumericIndex | complex) -> NumericIndex: ...
-    def __rfloordiv__(self, other: NumericIndex | complex) -> NumericIndex: ...
+    def __add__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __radd__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __sub__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __rsub__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __mul__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __rmul__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __truediv__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __rtruediv__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __floordiv__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
+    def __rfloordiv__(self, other: NumericIndex | complex) -> NumericIndex: ...  # type: ignore[override]
 
 class IntegerIndex(NumericIndex):
     def __contains__(self, key) -> bool: ...

pyproject.toml

@@ -43,7 +43,7 @@ poethepoet = ">=0.16.5"
 loguru = ">=0.6.0"
 pandas = "1.5.2"
 numpy = "<=1.23.5"
-typing-extensions = ">=4.2.0"
+typing-extensions = ">=4.4.0"
 matplotlib = ">=3.5.1"
 pre-commit = ">=2.19.0"
 black = ">=22.12.0"

tests/test_indexes.py

@@ -684,3 +684,31 @@ def test_sorted_and_list() -> None:
         ),
         list,
     )
+
+
+def test_index_operators() -> None:
+    # GH 405
+    i1 = pd.Index([1, 2, 3])
+    i2 = pd.Index([4, 5, 6])
+
+    check(assert_type(i1 + i2, pd.Index), pd.Index)
+    check(assert_type(i1 + 10, pd.Index), pd.Index)
+    check(assert_type(10 + i1, pd.Index), pd.Index)
+    check(assert_type(i1 - i2, pd.Index), pd.Index)
+    check(assert_type(i1 - 10, pd.Index), pd.Index)
+    check(assert_type(10 - i1, pd.Index), pd.Index)
+    check(assert_type(i1 * i2, pd.Index), pd.Index)
+    check(assert_type(i1 * 10, pd.Index), pd.Index)
+    check(assert_type(10 * i1, pd.Index), pd.Index)
+    check(assert_type(i1 / i2, pd.Index), pd.Index)
+    check(assert_type(i1 / 10, pd.Index), pd.Index)
+    check(assert_type(10 / i1, pd.Index), pd.Index)
+    check(assert_type(i1 // i2, pd.Index), pd.Index)
+    check(assert_type(i1 // 10, pd.Index), pd.Index)
+    check(assert_type(10 // i1, pd.Index), pd.Index)
+    check(assert_type(i1**i2, pd.Index), pd.Index)
+    check(assert_type(i1**2, pd.Index), pd.Index)
+    check(assert_type(2**i1, pd.Index), pd.Index)
+    check(assert_type(i1 % i2, pd.Index), pd.Index)
+    check(assert_type(i1 % 10, pd.Index), pd.Index)
+    check(assert_type(10 % i1, pd.Index), pd.Index)