fixup! REF: IntervalIndex[IntervalArray]

Author: TomAugspurger

pandas/core/indexes/interval.py

@@ -412,7 +412,8 @@ def copy(self, deep=False, name=None):
 
     @Appender(_index_shared_docs['astype'])
     def astype(self, dtype, copy=True):
-        new_values = self.values.astype(dtype, copy=copy)
+        with rewrite_exception('IntervalArray', self.__class__.__name__):
+            new_values = self.values.astype(dtype, copy=copy)
         if is_interval_dtype(new_values):
             return self._shallow_copy(new_values.left, new_values.right)
         return super(IntervalIndex, self).astype(dtype, copy=copy)

pandas/tests/indexes/interval/test_astype.py

@@ -51,7 +51,7 @@ def test_astype_category(self, index):
         'timedelta64', 'timedelta64[ns]', 'datetime64', 'datetime64[ns]',
         'datetime64[ns, US/Eastern]'])
     def test_astype_cannot_cast(self, index, dtype):
-        msg = 'Cannot cast IntervalArray to dtype'
+        msg = 'Cannot cast IntervalIndex to dtype'
         with tm.assert_raises_regex(TypeError, msg):
             index.astype(dtype)
 

pandas/tests/test_base.py

@@ -1194,7 +1194,8 @@ def test_iter_box(self):
      'datetime64[ns, US/Central]'),
     (pd.TimedeltaIndex([10**10]), np.ndarray, 'm8[ns]'),
     (pd.PeriodIndex([2018, 2019], freq='A'), np.ndarray, 'object'),
-    (pd.IntervalIndex.from_breaks([0, 1, 2]), pd.core.arrays.IntervalArray, 'interval'),
+    (pd.IntervalIndex.from_breaks([0, 1, 2]), pd.core.arrays.IntervalArray,
+     'interval'),
 ])
 def test_values_consistent(array, expected_type, dtype):
     l_values = pd.Series(array)._values