Skip to content

TST: Add test DataFrame.join with CategoricalIndex #62812

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Nov 1, 2025
Merged

TST: Add test DataFrame.join with CategoricalIndex #62812

Changes from 2 commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
1a3bee7
add test for issue #61675
matiaslindgren Oct 24, 2025
26b81c3
Merge branch 'main' into issue61675
matiaslindgren Oct 28, 2025
fa6d1fd
cleanup test
matiaslindgren Nov 1, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
38 changes: 38 additions & 0 deletions pandas/tests/frame/methods/test_join.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -575,3 +575,41 @@ def test_frame_join_tzaware(self):

tm.assert_index_equal(result.index, expected)
assert result.index.tz.key == "US/Central"

def test_frame_join_categorical_index(self):
# GH 61675
cat_data = pd.Categorical(
[15, 16, 17, 18],
categories=pd.Series(list(range(3, 24)), dtype="Int64"),
Copy link
Member

@rhshadrach rhshadrach Oct 31, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Can you reduce the size here; even 20 elements can make stepping through with a debugger harder. Shoot for 3 or 5 if necessary.

ordered=True,
)
values1 = "a b c d".split()
values2 = "xyzzy foo bar ...".split()
df1 = DataFrame({"hr": cat_data, "values1": values1}).set_index("hr")
df2 = DataFrame({"hr": cat_data, "values2": values2}).set_index("hr")
df1.columns = pd.CategoricalIndex([4], dtype=cat_data.dtype, name="other_hr")
df2.columns = pd.CategoricalIndex([3], dtype=cat_data.dtype, name="other_hr")

df_joined_1 = (
df1.reset_index(level="hr")
.merge(df2.reset_index(level="hr"), on="hr")
.set_index("hr")
)
Copy link
Member

@rhshadrach rhshadrach Oct 31, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

There are three method calls, it isn't clear what you're testing here. Can you move what you need to into the setup and have just a single method call here? Part of this may be dropping the last .set_index altogether - ideally we check the output directly from the function we want to test (merge here, I think) and do not modify the result.

Copy link
Contributor Author

@matiaslindgren matiaslindgren Nov 1, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Actually, I realized this test is redundant, sorry for the noise. I wanted to include the examples from the original GH issue unchanged, but since DataFrame.merge was a given as a suggested workaround for the bug we are testing, I think we can skip it and just test the join.

expected1 = DataFrame(
{"hr": cat_data, "values1": values1, "values2": values2}
).set_index("hr")
expected1.columns = Index([4, 3], dtype="object", name="other_hr")

tm.assert_frame_equal(df_joined_1, expected1)

df_joined_2 = df1.join(df2)
Copy link
Member

@rhshadrach rhshadrach Oct 31, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Can you separate this out to a second test.

expected2 = DataFrame(
{"hr": cat_data, "values1": values1, "values2": values2}
).set_index("hr")
expected2.columns = pd.CategoricalIndex(
[4, 3], dtype=cat_data.dtype, name="other_hr"
)

tm.assert_frame_equal(df_joined_2, expected2)

assert df_joined_1.equals(df_joined_2)
Copy link
Member

@rhshadrach rhshadrach Oct 31, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I don't think this is necessary. assert_frame_equal is checking the full state of the objects already.

Loading