tests not passing but i need to rebase again

pandas/core/dtypes/concat.py

@@ -125,6 +125,20 @@ def is_nonempty(x) -> bool:
  if any_ea:
  # we ignore axis here, as internally concatting with EAs is always
  # for axis=0
+ if any(is_categorical_dtype(x.dtype) for x in to_concat):
+ first = [x for x in to_concat if is_categorical_dtype(x.dtype)][0]
+ from pandas import Index
+ try:
+ codes = np.concatenate([Index(first)._is_dtype_compat(Index(c)).codes for c in to_concat])
+ except TypeError:
+ # not all to_concat elements are among our categories (or NA)
+ pass
+ else:
+ cat = first._from_backing_data(codes)
+ if first.ordered:
+ cat = cat.as_ordered()
+ return cat
+
  if not single_dtype:
  target_dtype = find_common_type([x.dtype for x in to_concat])
  to_concat = [cast_to_common_type(arr, target_dtype) for arr in to_concat]

pandas/core/indexes/category.py

@@ -548,6 +548,8 @@ def map(self, mapper):
  return Index(mapped, name=self.name)
 
  def _concat(self, to_concat: list[Index], name: Hashable) -> Index:
+ alt = Index._concat(self, to_concat, name=name) # uses concat_compat
+
  # if calling index is category, don't check dtype of others
  try:
  codes = np.concatenate([self._is_dtype_compat(c).codes for c in to_concat])
@@ -556,7 +558,11 @@ def _concat(self, to_concat: list[Index], name: Hashable) -> Index:
  from pandas.core.dtypes.concat import concat_compat
 
  res = concat_compat(to_concat)
- return Index(res, name=name)
+ out = Index(res, name=name)
+ assert out.equals(alt)
+ assert out.dtype == alt.dtype
+ return out
  else:
  cat = self._data._from_backing_data(codes)
+ assert cat.dtype == alt.dtype
  return type(self)._simple_new(cat, name=name)

pandas/tests/base/test_value_counts.py

@@ -43,7 +43,8 @@ def test_value_counts(index_or_series_obj):
 
 
 @pytest.mark.parametrize("null_obj", [np.nan, None])
-def test_value_counts_null(null_obj, index_or_series_obj):
+@pytest.mark.parametrize("dropna", [True, False])
+def test_value_counts_null(null_obj, dropna, index_or_series_obj):
  orig = index_or_series_obj
  obj = orig.copy()
 
@@ -70,20 +71,14 @@ def test_value_counts_null(null_obj, index_or_series_obj):
  expected = Series(dict(counter.most_common()), dtype=np.int64)
  expected.index = expected.index.astype(obj.dtype)
 
- result = obj.value_counts()
- if obj.duplicated().any():
- # TODO:
- # Order of entries with the same count is inconsistent on CI (gh-32449)
- expected = expected.sort_index()
- result = result.sort_index()
- tm.assert_series_equal(result, expected)
+ if not dropna:
+ # can't use expected[null_obj] = 3 as
+ # IntervalIndex doesn't allow assignment
+ new_entry = Series({np.nan: 3}, dtype=np.int64)
+ expected = expected.append(new_entry)
 
- # can't use expected[null_obj] = 3 as
- # IntervalIndex doesn't allow assignment
- new_entry = Series({np.nan: 3}, dtype=np.int64)
- expected = expected.append(new_entry)
+ result = obj.value_counts(dropna=dropna)
 
- result = obj.value_counts(dropna=False)
  if obj.duplicated().any():
  # TODO:
  # Order of entries with the same count is inconsistent on CI (gh-32449)