gosh-dataset 0.2.1

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// [[file:../parquet.note::4ca86f0d][4ca86f0d]]
/// Simple example
use arrow2::array::Array;
use arrow2_convert::{deserialize::TryIntoCollection, serialize::TryIntoArrow, ArrowDeserialize, ArrowField, ArrowSerialize};

#[derive(Debug, Clone, PartialEq, Eq, ArrowField, ArrowSerialize, ArrowDeserialize)]
pub struct Foo {
    name: String,
}

#[test]
fn test_simple_roundtrip() {
    // an item
    let original_array = [
        Foo {
            name: "hello".to_string(),
        },
        Foo {
            name: "one more".to_string(),
        },
        Foo {
            name: "good bye".to_string(),
        },
    ];

    // serialize to an arrow array. try_into_arrow() is enabled by the TryIntoArrow trait
    let arrow_array: Box<dyn Array> = original_array.try_into_arrow().unwrap();

    // which can be cast to an Arrow StructArray and be used for all kinds of IPC, FFI, etc.
    // supported by `arrow2`
    let struct_array = arrow_array.as_any().downcast_ref::<arrow2::array::StructArray>().unwrap();
    assert_eq!(struct_array.len(), 3);

    // deserialize back to our original vector via TryIntoCollection trait.
    let round_trip_array: Vec<Foo> = arrow_array.try_into_collection().unwrap();
    assert_eq!(round_trip_array, original_array);
}
// 4ca86f0d ends here