TST: Test pivot_table() with categorical data (#28803)

Author: ryankarlos

pandas/tests/reshape/test_pivot.py

@@ -1656,6 +1656,51 @@ def test_categorical_margins_category(self, observed):
  table = df.pivot_table("x", "y", "z", dropna=observed, margins=True)
  tm.assert_frame_equal(table, expected)
 
+ def test_pivot_with_categorical(self, observed, ordered_fixture):
+ # gh-21370
+ idx = [np.nan, "low", "high", "low", np.nan]
+ col = [np.nan, "A", "B", np.nan, "A"]
+ df = pd.DataFrame(
+ {
+ "In": pd.Categorical(
+ idx, categories=["low", "high"], ordered=ordered_fixture
+ ),
+ "Col": pd.Categorical(
+ col, categories=["A", "B"], ordered=ordered_fixture
+ ),
+ "Val": range(1, 6),
+ }
+ )
+ # case with index/columns/value
+ result = df.pivot_table(
+ index="In", columns="Col", values="Val", observed=observed
+ )
+
+ expected_cols = pd.CategoricalIndex(
+ ["A", "B"], ordered=ordered_fixture, name="Col"
+ )
+
+ expected = pd.DataFrame(
+ data=[[2.0, np.nan], [np.nan, 3.0]], columns=expected_cols
+ )
+ expected.index = Index(
+ pd.Categorical(
+ ["low", "high"], categories=["low", "high"], ordered=ordered_fixture
+ ),
+ name="In",
+ )
+
+ tm.assert_frame_equal(result, expected)
+
+ # case with columns/value
+ result = df.pivot_table(columns="Col", values="Val", observed=observed)
+
+ expected = pd.DataFrame(
+ data=[[3.5, 3.0]], columns=expected_cols, index=Index(["Val"])
+ )
+
+ tm.assert_frame_equal(result, expected)
+
  def test_categorical_aggfunc(self, observed):
  # GH 9534
  df = pd.DataFrame(