ENH: Add to_tuples method to IntervalIndex (#538)

Add to_tuples method to IntervalIndex

Author: skatsuta

pandas-stubs/core/indexes/interval.pyi

@@ -210,6 +210,7 @@ class IntervalIndex(IntervalMixin, Generic[IntervalT]):
         copy: bool = ...,
         dtype: IntervalDtype | None = ...,
     ) -> IntervalIndex[pd.Interval[pd.Timedelta]]: ...
+    def to_tuples(self, na_tuple: bool = ...) -> pd.Index: ...
     @overload
     def __contains__(self, key: IntervalT) -> bool: ...  # type: ignore[misc]
     @overload

tests/test_interval_index.py

@@ -33,6 +33,11 @@ def test_from_tuples() -> None:
     )
 
 
+def test_to_tuples() -> None:
+    ind = pd.IntervalIndex.from_tuples([(0, 1), (1, 2)]).to_tuples()
+    check(assert_type(ind, pd.Index), pd.Index, tuple)
+
+
 def test_is_overlapping() -> None:
     ind = pd.IntervalIndex.from_tuples([(0, 2), (1, 3), (4, 5)])
     check(assert_type(ind.is_overlapping, bool), bool)