Only if index

Author: mroeschke

pandas/core/indexes/range.py

@@ -29,6 +29,7 @@
     doc,
 )
 
+from pandas.core.dtypes import missing
 from pandas.core.dtypes.common import (
     ensure_platform_int,
     ensure_python_int,
@@ -472,7 +473,7 @@ def _shallow_copy(self, values, name: Hashable = no_default):
             # GH 46675 & 43885: If values is equally spaced, return a
             # more memory-compact RangeIndex instead of Index with 64-bit dtype
             diff = values[1] - values[0]
-            if diff != 0:
+            if not missing.isna(diff) and diff != 0:
                 maybe_range_indexer, remainder = np.divmod(values - values[0], diff)
                 if (
                     lib.is_range_indexer(maybe_range_indexer, len(maybe_range_indexer))
@@ -488,7 +489,8 @@ def _view(self) -> Self:
         return result
 
     def _wrap_reindex_result(self, target, indexer, preserve_names: bool):
-        target = self._shallow_copy(target._values)
+        if target.dtype.kind == "i":
+            target = self._shallow_copy(target._values)
         return super()._wrap_reindex_result(target, indexer, preserve_names)
 
     @doc(Index.copy)

pandas/tests/indexing/test_loc.py

@@ -1204,10 +1204,7 @@ def test_loc_setitem_empty_append_raises(self):
         data = [1, 2]
         df = DataFrame(columns=["x", "y"])
         df.index = df.index.astype(np.int64)
-        msg = (
-            rf"None of \[Index\(\[0, 1\], dtype='{np.dtype(int)}'\)\] "
-            r"are in the \[index\]"
-        )
+        msg = r"None of .*Index.* are in the \[index\]"
         with pytest.raises(KeyError, match=msg):
             df.loc[[0, 1], "x"] = data