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vortex_array/arrays/varbinview/compute/
take.rs

1// SPDX-License-Identifier: Apache-2.0
2// SPDX-FileCopyrightText: Copyright the Vortex contributors
3
4use std::iter;
5use std::sync::Arc;
6
7use num_traits::AsPrimitive;
8use vortex_buffer::Buffer;
9use vortex_error::VortexResult;
10use vortex_mask::AllOr;
11use vortex_mask::Mask;
12
13use crate::ArrayRef;
14use crate::IntoArray;
15use crate::array::ArrayView;
16use crate::arrays::PrimitiveArray;
17use crate::arrays::VarBinView;
18use crate::arrays::VarBinViewArray;
19use crate::arrays::dict::TakeExecute;
20use crate::arrays::varbinview::BinaryView;
21use crate::buffer::BufferHandle;
22use crate::executor::ExecutionCtx;
23use crate::match_each_integer_ptype;
24
25impl TakeExecute for VarBinView {
26    /// Take involves creating a new array that references the old array, just with the given set of views.
27    fn take(
28        array: ArrayView<'_, VarBinView>,
29        indices: &ArrayRef,
30        ctx: &mut ExecutionCtx,
31    ) -> VortexResult<Option<ArrayRef>> {
32        let validity = array.validity()?.take(indices)?;
33        let indices = indices.clone().execute::<PrimitiveArray>(ctx)?;
34
35        let indices_mask = indices
36            .as_ref()
37            .validity()?
38            .to_mask(indices.as_ref().len(), ctx)?;
39        let views_buffer = match_each_integer_ptype!(indices.ptype(), |I| {
40            take_views(array.views(), indices.as_slice::<I>(), &indices_mask)
41        });
42
43        // SAFETY: taking all components at same indices maintains invariants
44        unsafe {
45            Ok(Some(
46                VarBinViewArray::new_handle_unchecked(
47                    BufferHandle::new_host(views_buffer.into_byte_buffer()),
48                    Arc::clone(array.data_buffers()),
49                    array
50                        .dtype()
51                        .union_nullability(indices.dtype().nullability()),
52                    validity,
53                )
54                .into_array(),
55            ))
56        }
57    }
58}
59
60fn take_views<I: AsPrimitive<usize>>(
61    views_ref: &[BinaryView],
62    indices: &[I],
63    mask: &Mask,
64) -> Buffer<BinaryView> {
65    // NOTE(ngates): this deref is not actually trivial, so we run it once.
66    // We do not use iter_bools directly, since the resulting dyn iterator cannot
67    // implement TrustedLen.
68    match mask.bit_buffer() {
69        AllOr::All => {
70            Buffer::<BinaryView>::from_trusted_len_iter(indices.iter().map(|i| views_ref[i.as_()]))
71        }
72        AllOr::None => Buffer::<BinaryView>::from_trusted_len_iter(iter::repeat_n(
73            BinaryView::default(),
74            indices.len(),
75        )),
76        AllOr::Some(buffer) => Buffer::<BinaryView>::from_trusted_len_iter(
77            buffer.iter().zip(indices.iter()).map(|(valid, idx)| {
78                if valid {
79                    views_ref[idx.as_()]
80                } else {
81                    BinaryView::default()
82                }
83            }),
84        ),
85    }
86}
87
88#[cfg(test)]
89mod tests {
90    use rstest::rstest;
91    use vortex_buffer::BitBuffer;
92    use vortex_buffer::buffer;
93
94    use crate::IntoArray;
95    use crate::accessor::ArrayAccessor;
96    use crate::arrays::VarBinViewArray;
97    use crate::arrays::varbinview::compute::take::PrimitiveArray;
98    use crate::canonical::ToCanonical;
99    use crate::compute::conformance::take::test_take_conformance;
100    use crate::dtype::DType;
101    use crate::dtype::Nullability::NonNullable;
102    use crate::validity::Validity;
103
104    #[test]
105    fn take_nullable() {
106        let arr = VarBinViewArray::from_iter_nullable_str([
107            Some("one"),
108            None,
109            Some("three"),
110            Some("four"),
111            None,
112            Some("six"),
113        ]);
114
115        let taken = arr.take(buffer![0, 3].into_array()).unwrap();
116
117        assert!(taken.dtype().is_nullable());
118        assert_eq!(
119            taken.to_varbinview().with_iterator(|it| it
120                .map(|v| v.map(|b| unsafe { String::from_utf8_unchecked(b.to_vec()) }))
121                .collect::<Vec<_>>()),
122            [Some("one".to_string()), Some("four".to_string())]
123        );
124    }
125
126    #[test]
127    fn take_nullable_indices() {
128        let arr = VarBinViewArray::from_iter(["one", "two"].map(Some), DType::Utf8(NonNullable));
129
130        let indices = PrimitiveArray::new(
131            // Verify that garbage values at NULL indices are ignored.
132            buffer![1u64, 999],
133            Validity::from(BitBuffer::from(vec![true, false])),
134        );
135
136        let taken = arr.take(indices.into_array()).unwrap();
137
138        assert!(taken.dtype().is_nullable());
139        assert_eq!(
140            taken.to_varbinview().with_iterator(|it| it
141                .map(|v| v.map(|b| unsafe { String::from_utf8_unchecked(b.to_vec()) }))
142                .collect::<Vec<_>>()),
143            [Some("two".to_string()), None]
144        );
145    }
146
147    #[rstest]
148    #[case(VarBinViewArray::from_iter(
149        ["hello", "world", "test", "data", "array"].map(Some),
150        DType::Utf8(NonNullable),
151    ))]
152    #[case(VarBinViewArray::from_iter_nullable_str([
153        Some("hello"),
154        None,
155        Some("test"),
156        Some("data"),
157        None,
158    ]))]
159    #[case(VarBinViewArray::from_iter(
160        [b"hello".as_slice(), b"world", b"test", b"data", b"array"].map(Some),
161        DType::Binary(NonNullable),
162    ))]
163    #[case(VarBinViewArray::from_iter(["single"].map(Some), DType::Utf8(NonNullable)))]
164    fn test_take_varbinview_conformance(#[case] array: VarBinViewArray) {
165        test_take_conformance(&array.into_array());
166    }
167}