arrow2 0.10.1

Unofficial implementation of Apache Arrow spec in safe Rust
Documentation 
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use parquet2::{
    encoding::Encoding, metadata::ColumnDescriptor, page::DataPage, types::NativeType,
    write::WriteOptions,
};

use super::super::levels;
use super::super::utils;
use super::basic::{build_statistics, encode_plain};
use crate::{
    array::{Array, Offset, PrimitiveArray},
    error::Result,
    io::parquet::read::is_type_nullable,
    types::NativeType as ArrowNativeType,
};

pub fn array_to_page<T, R, O>(
    array: &PrimitiveArray<T>,
    options: WriteOptions,
    descriptor: ColumnDescriptor,
    nested: levels::NestedInfo<O>,
) -> Result<DataPage>
where
    T: ArrowNativeType,
    R: NativeType,
    T: num_traits::AsPrimitive<R>,
    O: Offset,
{
    let is_optional = is_type_nullable(descriptor.type_());

    let validity = array.validity();

    let mut buffer = vec![];
    levels::write_rep_levels(&mut buffer, &nested, options.version)?;
    let repetition_levels_byte_length = buffer.len();

    levels::write_def_levels(&mut buffer, &nested, validity, options.version)?;
    let definition_levels_byte_length = buffer.len() - repetition_levels_byte_length;

    encode_plain(array, is_optional, &mut buffer);

    let statistics = if options.write_statistics {
        Some(build_statistics(array, descriptor.clone()))
    } else {
        None
    };

    utils::build_plain_page(
        buffer,
        levels::num_values(nested.offsets()),
        array.null_count(),
        repetition_levels_byte_length,
        definition_levels_byte_length,
        statistics,
        descriptor,
        options,
        Encoding::Plain,
    )
}