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: #16311

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.

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

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:

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"])
 
 

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()]],
+    )

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)]],
+    )

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)])]],
+    )