BUG: assert_index_equal ignoring names when check_order is false (#47330)

* BUG: assert_index_equal ignoring names when check_order is false * Update doc/source/whatsnew/v1.5.0.rst Co-authored-by: Simon Hawkins <simonjayhawkins@gmail.com> * Move index creation to else block * Remove dtypes Co-authored-by: Simon Hawkins <simonjayhawkins@gmail.com>

Author: phofl

doc/source/whatsnew/v1.5.0.rst

@@ -970,7 +970,7 @@ Other
 
 .. ***DO NOT USE THIS SECTION***
 
--
+- Bug in :func:`.assert_index_equal` with ``names=True`` and ``check_order=False`` not checking names (:issue:`47328`)
 -
 
 .. ---------------------------------------------------------------------------

pandas/_testing/asserters.py

@@ -45,10 +45,7 @@
  Series,
  TimedeltaIndex,
 )
-from pandas.core.algorithms import (
- safe_sort,
- take_nd,
-)
+from pandas.core.algorithms import take_nd
 from pandas.core.arrays import (
  DatetimeArray,
  ExtensionArray,
@@ -58,6 +55,7 @@
 )
 from pandas.core.arrays.datetimelike import DatetimeLikeArrayMixin
 from pandas.core.arrays.string_ import StringDtype
+from pandas.core.indexes.api import safe_sort_index
 
 from pandas.io.formats.printing import pprint_thing
 
@@ -367,8 +365,8 @@ def _get_ilevel_values(index, level):
 
  # If order doesn't matter then sort the index entries
  if not check_order:
- left = Index(safe_sort(left), dtype=left.dtype)
- right = Index(safe_sort(right), dtype=right.dtype)
+ left = safe_sort_index(left)
+ right = safe_sort_index(right)
 
  # MultiIndex special comparison for little-friendly error messages
  if left.nlevels > 1:

pandas/core/indexes/api.py

@@ -70,6 +70,7 @@
  "get_unanimous_names",
  "all_indexes_same",
  "default_index",
+ "safe_sort_index",
 ]
 
 
@@ -157,23 +158,42 @@ def _get_combined_index(
  index = ensure_index(index)
 
  if sort:
- try:
- array_sorted = safe_sort(index)
- array_sorted = cast(np.ndarray, array_sorted)
- if isinstance(index, MultiIndex):
- index = MultiIndex.from_tuples(array_sorted, names=index.names)
- else:
- index = Index(array_sorted, name=index.name)
- except TypeError:
- pass
-
+ index = safe_sort_index(index)
  # GH 29879
  if copy:
  index = index.copy()
 
  return index
 
 
+def safe_sort_index(index: Index) -> Index:
+ """
+ Returns the sorted index
+
+ We keep the dtypes and the name attributes.
+
+ Parameters
+ ----------
+ index : an Index
+
+ Returns
+ -------
+ Index
+ """
+ try:
+ array_sorted = safe_sort(index)
+ except TypeError:
+ pass
+ else:
+ array_sorted = cast(np.ndarray, array_sorted)
+ if isinstance(index, MultiIndex):
+ index = MultiIndex.from_tuples(array_sorted, names=index.names)
+ else:
+ index = Index(array_sorted, name=index.name, dtype=index.dtype)
+
+ return index
+
+
 def union_indexes(indexes, sort: bool | None = True) -> Index:
  """
  Return the union of indexes.

pandas/tests/util/test_assert_index_equal.py

@@ -238,6 +238,14 @@ def test_index_equal_range_categories(check_categorical, exact):
  )
 
 
+def test_assert_index_equal_different_names_check_order_false():
+ # GH#47328
+ idx1 = Index([1, 3], name="a")
+ idx2 = Index([3, 1], name="b")
+ with pytest.raises(AssertionError, match='"names" are different'):
+ tm.assert_index_equal(idx1, idx2, check_order=False, check_names=True)
+
+
 def test_assert_index_equal_mixed_dtype():
  # GH#39168
  idx = Index(["foo", "bar", 42])