ENH: gb.is_monotonic_increasing #17015 tests revised and passing

pandas/tests/groupby/test_groupby.py

@@ -2610,9 +2610,9 @@ def test_is_monotonic_increasing(self, in_vals, out_vals):
  'B': ['a', 'a', 'a', 'b', 'b', 'b', 'c', 'c', 'c', 'd', 'd'],
  'C': in_vals}
  df = pd.DataFrame(source_dict)
- result = df.groupby(['B']).C.is_monotonic_increasing()
- expected = pd.Series(index=list('abcd'), name='B')
-
+ result = df.groupby('B').C.is_monotonic_increasing()
+ expected = pd.Series(index=list('abcd'), data=out_vals, name='C')
+ expected.index.name = 'B'
  tm.assert_series_equal(result, expected)
 
  # Also check result equal to manually taking x.is_monotonic_increasing.
@@ -2641,7 +2641,8 @@ def test_is_monotonic_decreasing(self, in_vals, out_vals):
 
  df = pd.DataFrame(source_dict)
  result = df.groupby('B').C.is_monotonic_decreasing()
- expected = pd.Series(index=list('abcd'), name='B')
+ expected = pd.Series(index=list('abcd'), data=out_vals, name='C')
+ expected.index.name = 'B'
  tm.assert_series_equal(result, expected)
 
  def test_apply_numeric_coercion_when_datetime(self):