argsort

Author: MarcoGorelli

pandas-stubs/core/indexes/base.pyi

@@ -479,7 +479,7 @@ class Index(IndexOpsMixin[S1], ElementOpsMixin[S1]):
     ): ...
     @final
     def sort(self, *args: Any, **kwargs: Any) -> None: ...
-    def argsort(self, *args: Any, **kwargs: Any): ...
+    def argsort(self, *args: Any, **kwargs: Any) -> np_1darray[np.intp]: ...
     def get_indexer_non_unique(self, target): ...
     @final
     def get_indexer_for(self, target, **kwargs: Any): ...

tests/indexes/test_rangeindex.py

@@ -54,3 +54,11 @@ def test_rangeindex_get_indexer() -> None:
         assert_type(ri.get_indexer(ri), np_1darray[np.intp]),
         np_1darray[np.intp],
     )
+
+
+def test_rangeindex_argsort() -> None:
+    ri = pd.RangeIndex.from_range(range(3))
+    check(
+        assert_type(ri.argsort(), np_1darray[np.intp]),
+        np_1darray[np.intp],
+    )