Return view for xs when droplevel=False with regular Index (#37832)

Author: phofl

pandas/core/generic.py

@@ -3759,7 +3759,7 @@ class animal locomotion
  dtype=new_values.dtype,
  )
  elif is_scalar(loc):
- result = self.iloc[:, [loc]]
+ result = self.iloc[:, slice(loc, loc + 1)]
  elif axis == 1:
  result = self.iloc[:, loc]
  else:

pandas/tests/frame/indexing/test_xs.py

@@ -319,3 +319,11 @@ def test_xs_droplevel_false(self):
  result = df.xs("a", axis=1, drop_level=False)
  expected = DataFrame({"a": [1]})
  tm.assert_frame_equal(result, expected)
+
+ def test_xs_droplevel_false_view(self):
+ # GH#37832
+ df = DataFrame([[1, 2, 3]], columns=Index(["a", "b", "c"]))
+ result = df.xs("a", axis=1, drop_level=False)
+ df.values[0, 0] = 2
+ expected = DataFrame({"a": [2]})
+ tm.assert_frame_equal(result, expected)