vortex_array/arrays/primitive/

mod.rs

// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright the Vortex contributors

use std::fmt::Debug;
use std::iter;

mod accessor;

use arrow_buffer::BooleanBufferBuilder;
use vortex_buffer::{Alignment, Buffer, BufferMut, ByteBuffer, ByteBufferMut};
use vortex_dtype::{DType, NativePType, Nullability, PType, match_each_native_ptype};
use vortex_error::{VortexResult, vortex_panic};

use crate::builders::ArrayBuilder;
use crate::stats::{ArrayStats, StatsSetRef};
use crate::validity::Validity;
use crate::{Array, ArrayRef, Canonical, EncodingId, EncodingRef, IntoArray, vtable};

mod compute;
mod native_value;
mod ops;
mod patch;
mod serde;
mod top_value;

pub use compute::{IS_CONST_LANE_WIDTH, compute_is_constant};
pub use native_value::NativeValue;

use crate::vtable::{
    ArrayVTable, CanonicalVTable, NotSupported, VTable, ValidityHelper,
    ValidityVTableFromValidityHelper,
};

vtable!(Primitive);

impl VTable for PrimitiveVTable {
    type Array = PrimitiveArray;
    type Encoding = PrimitiveEncoding;

    type ArrayVTable = Self;
    type CanonicalVTable = Self;
    type OperationsVTable = Self;
    type ValidityVTable = ValidityVTableFromValidityHelper;
    type VisitorVTable = Self;
    type ComputeVTable = NotSupported;
    type EncodeVTable = NotSupported;
    type SerdeVTable = Self;

    fn id(_encoding: &Self::Encoding) -> EncodingId {
        EncodingId::new_ref("vortex.primitive")
    }

    fn encoding(_array: &Self::Array) -> EncodingRef {
        EncodingRef::new_ref(PrimitiveEncoding.as_ref())
    }
}

/// A primitive array that stores [native types][vortex_dtype::NativePType] in a contiguous buffer
/// of memory, along with an optional validity child.
///
/// This mirrors the Apache Arrow Primitive layout and can be converted into and out of one
/// without allocations or copies.
///
/// The underlying buffer must be natively aligned to the primitive type they are representing.
///
/// Values are stored in their native representation with proper alignment.
/// Null values still occupy space in the buffer but are marked invalid in the validity mask.
///
/// # Examples
///
/// ```
/// use vortex_array::arrays::PrimitiveArray;
/// use vortex_array::compute::sum;
/// ///
/// // Create from iterator using FromIterator impl
/// let array: PrimitiveArray = [1i32, 2, 3, 4, 5].into_iter().collect();
///
/// // Slice the array
/// let sliced = array.slice(1, 3);
///
/// // Access individual values
/// let value = sliced.scalar_at(0);
/// assert_eq!(value, 2i32.into());
///
/// // Convert into a type-erased array that can be passed to compute functions.
/// let summed = sum(sliced.as_ref()).unwrap().as_primitive().typed_value::<i64>().unwrap();
/// assert_eq!(summed, 5i64);
/// ```
#[derive(Clone, Debug)]
pub struct PrimitiveArray {
    dtype: DType,
    buffer: ByteBuffer,
    validity: Validity,
    stats_set: ArrayStats,
}

#[derive(Clone, Debug)]
pub struct PrimitiveEncoding;

impl PrimitiveArray {
    pub fn new<T: NativePType>(buffer: impl Into<Buffer<T>>, validity: Validity) -> Self {
        let buffer = buffer.into();
        if let Some(len) = validity.maybe_len()
            && buffer.len() != len
        {
            vortex_panic!(
                "Buffer and validity length mismatch: buffer={}, validity={}",
                buffer.len(),
                len
            );
        }

        Self {
            dtype: DType::Primitive(T::PTYPE, validity.nullability()),
            buffer: buffer.into_byte_buffer(),
            validity,
            stats_set: Default::default(),
        }
    }

    pub fn empty<T: NativePType>(nullability: Nullability) -> Self {
        Self::new(Buffer::<T>::empty(), nullability.into())
    }

    pub fn from_byte_buffer(buffer: ByteBuffer, ptype: PType, validity: Validity) -> Self {
        match_each_native_ptype!(ptype, |T| {
            Self::new::<T>(Buffer::from_byte_buffer(buffer), validity)
        })
    }

    /// Create a PrimitiveArray from an iterator of `T`.
    /// NOTE: we cannot impl FromIterator trait since it conflicts with `FromIterator<T>`.
    pub fn from_option_iter<T: NativePType, I: IntoIterator<Item = Option<T>>>(iter: I) -> Self {
        let iter = iter.into_iter();
        let mut values = BufferMut::with_capacity(iter.size_hint().0);
        let mut validity = BooleanBufferBuilder::new(values.capacity());

        for i in iter {
            match i {
                None => {
                    validity.append(false);
                    values.push(T::default());
                }
                Some(e) => {
                    validity.append(true);
                    values.push(e);
                }
            }
        }
        Self::new(values.freeze(), Validity::from(validity.finish()))
    }

    /// Create a PrimitiveArray from a byte buffer containing only the valid elements.
    pub fn from_values_byte_buffer(
        valid_elems_buffer: ByteBuffer,
        ptype: PType,
        validity: Validity,
        n_rows: usize,
    ) -> VortexResult<Self> {
        let byte_width = ptype.byte_width();
        let alignment = Alignment::new(byte_width);
        let buffer = match &validity {
            Validity::AllValid | Validity::NonNullable => valid_elems_buffer.aligned(alignment),
            Validity::AllInvalid => ByteBuffer::zeroed_aligned(n_rows * byte_width, alignment),
            Validity::Array(is_valid) => {
                let bool_array = is_valid.to_canonical()?.into_bool()?;
                let bool_buffer = bool_array.boolean_buffer();
                let mut bytes = ByteBufferMut::zeroed_aligned(n_rows * byte_width, alignment);
                for (i, valid_i) in bool_buffer.set_indices().enumerate() {
                    bytes[valid_i * byte_width..(valid_i + 1) * byte_width]
                        .copy_from_slice(&valid_elems_buffer[i * byte_width..(i + 1) * byte_width])
                }
                bytes.freeze()
            }
        };

        Ok(Self::from_byte_buffer(buffer, ptype, validity))
    }

    pub fn ptype(&self) -> PType {
        self.dtype().as_ptype()
    }

    pub fn byte_buffer(&self) -> &ByteBuffer {
        &self.buffer
    }

    pub fn into_byte_buffer(self) -> ByteBuffer {
        self.buffer
    }

    pub fn buffer<T: NativePType>(&self) -> Buffer<T> {
        if T::PTYPE != self.ptype() {
            vortex_panic!(
                "Attempted to get buffer of type {} from array of type {}",
                T::PTYPE,
                self.ptype()
            )
        }
        Buffer::from_byte_buffer(self.byte_buffer().clone())
    }

    pub fn into_buffer<T: NativePType>(self) -> Buffer<T> {
        if T::PTYPE != self.ptype() {
            vortex_panic!(
                "Attempted to get buffer of type {} from array of type {}",
                T::PTYPE,
                self.ptype()
            )
        }
        Buffer::from_byte_buffer(self.buffer)
    }

    /// Extract a mutable buffer from the PrimitiveArray. Attempts to do this with zero-copy
    /// if the buffer is uniquely owned, otherwise will make a copy.
    pub fn into_buffer_mut<T: NativePType>(self) -> BufferMut<T> {
        if T::PTYPE != self.ptype() {
            vortex_panic!(
                "Attempted to get buffer_mut of type {} from array of type {}",
                T::PTYPE,
                self.ptype()
            )
        }
        self.into_buffer()
            .try_into_mut()
            .unwrap_or_else(|buffer| BufferMut::<T>::copy_from(&buffer))
    }

    /// Try to extract a mutable buffer from the PrimitiveArray with zero copy.
    #[allow(clippy::panic_in_result_fn)]
    pub fn try_into_buffer_mut<T: NativePType>(self) -> Result<BufferMut<T>, PrimitiveArray> {
        if T::PTYPE != self.ptype() {
            vortex_panic!(
                "Attempted to get buffer_mut of type {} from array of type {}",
                T::PTYPE,
                self.ptype()
            )
        }
        let validity = self.validity().clone();
        Buffer::<T>::from_byte_buffer(self.into_byte_buffer())
            .try_into_mut()
            .map_err(|buffer| PrimitiveArray::new(buffer, validity))
    }

    /// Map each element in the array to a new value.
    ///
    /// This ignores validity and maps over all maybe-null elements.
    ///
    /// TODO(ngates): we could be smarter here if validity is sparse and only run the function
    ///   over the valid elements.
    pub fn map_each<T, R, F>(self, f: F) -> PrimitiveArray
    where
        T: NativePType,
        R: NativePType,
        F: FnMut(T) -> R,
    {
        let validity = self.validity().clone();
        let buffer = match self.try_into_buffer_mut() {
            Ok(buffer_mut) => buffer_mut.map_each(f),
            Err(parray) => BufferMut::<R>::from_iter(parray.buffer::<T>().iter().copied().map(f)),
        };
        PrimitiveArray::new(buffer.freeze(), validity)
    }

    /// Map each element in the array to a new value.
    ///
    /// This doesn't ignore validity and maps over all maybe-null elements, with a bool true if
    /// valid and false otherwise.
    pub fn map_each_with_validity<T, R, F>(self, f: F) -> VortexResult<PrimitiveArray>
    where
        T: NativePType,
        R: NativePType,
        F: FnMut((T, bool)) -> R,
    {
        let validity = self.validity();

        let buf_iter = self.buffer::<T>().into_iter();

        let buffer = match &validity {
            Validity::NonNullable | Validity::AllValid => {
                BufferMut::<R>::from_iter(buf_iter.zip(iter::repeat(true)).map(f))
            }
            Validity::AllInvalid => {
                BufferMut::<R>::from_iter(buf_iter.zip(iter::repeat(false)).map(f))
            }
            Validity::Array(val) => {
                let val = val.to_canonical()?.into_bool()?;
                BufferMut::<R>::from_iter(buf_iter.zip(val.boolean_buffer()).map(f))
            }
        };
        Ok(PrimitiveArray::new(buffer.freeze(), validity.clone()))
    }

    /// Return a slice of the array's buffer.
    ///
    /// NOTE: these values may be nonsense if the validity buffer indicates that the value is null.
    pub fn as_slice<T: NativePType>(&self) -> &[T] {
        if T::PTYPE != self.ptype() {
            vortex_panic!(
                "Attempted to get slice of type {} from array of type {}",
                T::PTYPE,
                self.ptype()
            )
        }
        let raw_slice = self.byte_buffer().as_ptr();
        // SAFETY: alignment of Buffer is checked on construction
        unsafe {
            std::slice::from_raw_parts(raw_slice.cast(), self.byte_buffer().len() / size_of::<T>())
        }
    }

    pub fn reinterpret_cast(&self, ptype: PType) -> Self {
        if self.ptype() == ptype {
            return self.clone();
        }

        assert_eq!(
            self.ptype().byte_width(),
            ptype.byte_width(),
            "can't reinterpret cast between integers of two different widths"
        );

        PrimitiveArray::from_byte_buffer(self.byte_buffer().clone(), ptype, self.validity().clone())
    }
}

impl ArrayVTable<PrimitiveVTable> for PrimitiveVTable {
    fn len(array: &PrimitiveArray) -> usize {
        array.byte_buffer().len() / array.ptype().byte_width()
    }

    fn dtype(array: &PrimitiveArray) -> &DType {
        &array.dtype
    }

    fn stats(array: &PrimitiveArray) -> StatsSetRef<'_> {
        array.stats_set.to_ref(array.as_ref())
    }
}

impl ValidityHelper for PrimitiveArray {
    fn validity(&self) -> &Validity {
        &self.validity
    }
}

impl<T: NativePType> FromIterator<T> for PrimitiveArray {
    fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self {
        let values = BufferMut::from_iter(iter);
        PrimitiveArray::new(values.freeze(), Validity::NonNullable)
    }
}

impl<T: NativePType> IntoArray for Buffer<T> {
    fn into_array(self) -> ArrayRef {
        PrimitiveArray::new(self, Validity::NonNullable).into_array()
    }
}

impl<T: NativePType> IntoArray for BufferMut<T> {
    fn into_array(self) -> ArrayRef {
        self.freeze().into_array()
    }
}

impl CanonicalVTable<PrimitiveVTable> for PrimitiveVTable {
    fn canonicalize(array: &PrimitiveArray) -> VortexResult<Canonical> {
        Ok(Canonical::Primitive(array.clone()))
    }

    fn append_to_builder(
        array: &PrimitiveArray,
        builder: &mut dyn ArrayBuilder,
    ) -> VortexResult<()> {
        builder.extend_from_array(array.as_ref())
    }
}

#[cfg(test)]
mod tests {
    use vortex_buffer::buffer;
    use vortex_scalar::PValue;

    use crate::arrays::{BoolArray, PrimitiveArray};
    use crate::compute::conformance::filter::test_filter_conformance;
    use crate::compute::conformance::mask::test_mask_conformance;
    use crate::compute::conformance::search_sorted::rstest_reuse::apply;
    use crate::compute::conformance::search_sorted::{search_sorted_conformance, *};
    use crate::search_sorted::{SearchResult, SearchSorted, SearchSortedSide};
    use crate::validity::Validity;
    use crate::{ArrayRef, IntoArray};

    #[apply(search_sorted_conformance)]
    fn test_search_sorted_primitive(
        #[case] array: ArrayRef,
        #[case] value: i32,
        #[case] side: SearchSortedSide,
        #[case] expected: SearchResult,
    ) {
        let res = array
            .as_primitive_typed()
            .search_sorted(&Some(PValue::from(value)), side);
        assert_eq!(res, expected);
    }

    #[test]
    fn test_mask_primitive_array() {
        test_mask_conformance(
            PrimitiveArray::new(buffer![0, 1, 2, 3, 4], Validity::NonNullable).as_ref(),
        );
        test_mask_conformance(
            PrimitiveArray::new(buffer![0, 1, 2, 3, 4], Validity::AllValid).as_ref(),
        );
        test_mask_conformance(
            PrimitiveArray::new(buffer![0, 1, 2, 3, 4], Validity::AllInvalid).as_ref(),
        );
        test_mask_conformance(
            PrimitiveArray::new(
                buffer![0, 1, 2, 3, 4],
                Validity::Array(
                    BoolArray::from_iter([true, false, true, false, true]).into_array(),
                ),
            )
            .as_ref(),
        );
    }

    #[test]
    fn test_filter_primitive_array() {
        // Test various sizes
        test_filter_conformance(
            PrimitiveArray::new(buffer![42i32], Validity::NonNullable).as_ref(),
        );
        test_filter_conformance(PrimitiveArray::new(buffer![0, 1], Validity::NonNullable).as_ref());
        test_filter_conformance(
            PrimitiveArray::new(buffer![0, 1, 2, 3, 4], Validity::NonNullable).as_ref(),
        );
        test_filter_conformance(
            PrimitiveArray::new(buffer![0, 1, 2, 3, 4, 5, 6, 7], Validity::NonNullable).as_ref(),
        );

        // Test with validity
        test_filter_conformance(
            PrimitiveArray::new(buffer![0, 1, 2, 3, 4], Validity::AllValid).as_ref(),
        );
        test_filter_conformance(
            PrimitiveArray::new(
                buffer![0, 1, 2, 3, 4, 5],
                Validity::Array(
                    BoolArray::from_iter([true, false, true, false, true, true]).into_array(),
                ),
            )
            .as_ref(),
        );
    }
}