From 6e37afc7c9e177b307c41950e52453bd5906af44 Mon Sep 17 00:00:00 2001
From: Matthew Roeschke <10647082+mroeschke@users.noreply.github.com>
Date: Fri, 19 Jul 2024 11:52:27 -1000
Subject: [PATCH] Make __bool__ raise for more cudf objects (#16311)

To match pandas, this PR makes `DataFrame`, `MultiIndex` and `RangeIndex` raise on `__bool__`.

Authors:
  - Matthew Roeschke (https://github.com/mroeschke)
  - GALI PREM SAGAR (https://github.com/galipremsagar)

Approvers:
  - GALI PREM SAGAR (https://github.com/galipremsagar)

URL: https://github.com/rapidsai/cudf/pull/16311
---
 python/cudf/cudf/core/_base_index.py         | 6 ++++++
 python/cudf/cudf/core/frame.py               | 6 ++++++
 python/cudf/cudf/core/single_column_frame.py | 6 ------
 python/cudf/cudf/tests/test_csv.py           | 2 +-
 python/cudf/cudf/tests/test_dataframe.py     | 9 +++++++++
 python/cudf/cudf/tests/test_index.py         | 9 +++++++++
 python/cudf/cudf/tests/test_multiindex.py    | 9 +++++++++
 7 files changed, 40 insertions(+), 7 deletions(-)

diff --git a/python/cudf/cudf/core/_base_index.py b/python/cudf/cudf/core/_base_index.py
index 479f87bb78b..657acc41b18 100644
--- a/python/cudf/cudf/core/_base_index.py
+++ b/python/cudf/cudf/core/_base_index.py
@@ -62,6 +62,12 @@ def copy(self, deep: bool = True) -> Self:
     def __len__(self):
         raise NotImplementedError
 
+    def __bool__(self):
+        raise ValueError(
+            f"The truth value of a {type(self).__name__} is ambiguous. Use "
+            "a.empty, a.bool(), a.item(), a.any() or a.all()."
+        )
+
     @property
     def size(self):
         # The size of an index is always its length irrespective of dimension.
diff --git a/python/cudf/cudf/core/frame.py b/python/cudf/cudf/core/frame.py
index 111225a5fc2..e3a2e840902 100644
--- a/python/cudf/cudf/core/frame.py
+++ b/python/cudf/cudf/core/frame.py
@@ -1587,6 +1587,12 @@ def __pos__(self):
     def __abs__(self):
         return self._unaryop("abs")
 
+    def __bool__(self):
+        raise ValueError(
+            f"The truth value of a {type(self).__name__} is ambiguous. Use "
+            "a.empty, a.bool(), a.item(), a.any() or a.all()."
+        )
+
     # Reductions
     @classmethod
     @_performance_tracking
diff --git a/python/cudf/cudf/core/single_column_frame.py b/python/cudf/cudf/core/single_column_frame.py
index 04c7db7a53c..7efe13d9b45 100644
--- a/python/cudf/cudf/core/single_column_frame.py
+++ b/python/cudf/cudf/core/single_column_frame.py
@@ -91,12 +91,6 @@ def shape(self) -> tuple[int]:
         """Get a tuple representing the dimensionality of the Index."""
         return (len(self),)
 
-    def __bool__(self):
-        raise TypeError(
-            f"The truth value of a {type(self)} is ambiguous. Use "
-            "a.empty, a.bool(), a.item(), a.any() or a.all()."
-        )
-
     @property  # type: ignore
     @_performance_tracking
     def _num_columns(self) -> int:
diff --git a/python/cudf/cudf/tests/test_csv.py b/python/cudf/cudf/tests/test_csv.py
index a22a627523f..0525b02b698 100644
--- a/python/cudf/cudf/tests/test_csv.py
+++ b/python/cudf/cudf/tests/test_csv.py
@@ -1617,7 +1617,7 @@ def test_csv_reader_partial_dtype(dtype):
         StringIO('"A","B","C"\n0,1,2'), dtype=dtype, usecols=["A", "C"]
     )
 
-    assert names_df == header_df
+    assert_eq(names_df, header_df)
     assert all(names_df.dtypes == ["int16", "int64"])
 
 
diff --git a/python/cudf/cudf/tests/test_dataframe.py b/python/cudf/cudf/tests/test_dataframe.py
index 2009fc49ce5..53ed5d728cb 100644
--- a/python/cudf/cudf/tests/test_dataframe.py
+++ b/python/cudf/cudf/tests/test_dataframe.py
@@ -11100,3 +11100,12 @@ def test_from_records_with_index_no_shallow_copy():
     data = np.array([(1.0, 2), (3.0, 4)], dtype=[("x", "<f8"), ("y", "<i8")])
     df = cudf.DataFrame(data.view(np.recarray), index=idx)
     assert df.index is idx
+
+
+def test_bool_raises():
+    assert_exceptions_equal(
+        lfunc=bool,
+        rfunc=bool,
+        lfunc_args_and_kwargs=[[cudf.DataFrame()]],
+        rfunc_args_and_kwargs=[[pd.DataFrame()]],
+    )
diff --git a/python/cudf/cudf/tests/test_index.py b/python/cudf/cudf/tests/test_index.py
index 9eba6122d26..722a64cb553 100644
--- a/python/cudf/cudf/tests/test_index.py
+++ b/python/cudf/cudf/tests/test_index.py
@@ -3294,3 +3294,12 @@ def test_index_assignment_no_shallow_copy(index):
     df = cudf.DataFrame(range(1))
     df.index = index
     assert df.index is index
+
+
+def test_bool_rangeindex_raises():
+    assert_exceptions_equal(
+        lfunc=bool,
+        rfunc=bool,
+        lfunc_args_and_kwargs=[[pd.RangeIndex(0)]],
+        rfunc_args_and_kwargs=[[cudf.RangeIndex(0)]],
+    )
diff --git a/python/cudf/cudf/tests/test_multiindex.py b/python/cudf/cudf/tests/test_multiindex.py
index 1941eec91eb..2c00d48266c 100644
--- a/python/cudf/cudf/tests/test_multiindex.py
+++ b/python/cudf/cudf/tests/test_multiindex.py
@@ -2161,3 +2161,12 @@ def test_nunique(array, dropna):
     result = gidx.nunique(dropna=dropna)
     expected = pidx.nunique(dropna=dropna)
     assert result == expected
+
+
+def test_bool_raises():
+    assert_exceptions_equal(
+        lfunc=bool,
+        rfunc=bool,
+        lfunc_args_and_kwargs=[[cudf.MultiIndex.from_arrays([range(1)])]],
+        rfunc_args_and_kwargs=[[pd.MultiIndex.from_arrays([range(1)])]],
+    )