arrow_json/reader/
null_array.rs

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// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

use crate::reader::tape::{Tape, TapeElement};
use crate::reader::ArrayDecoder;
use arrow_data::{ArrayData, ArrayDataBuilder};
use arrow_schema::{ArrowError, DataType};

#[derive(Default)]
pub struct NullArrayDecoder {}

impl ArrayDecoder for NullArrayDecoder {
    fn decode(&mut self, tape: &Tape<'_>, pos: &[u32]) -> Result<ArrayData, ArrowError> {
        for p in pos {
            if !matches!(tape.get(*p), TapeElement::Null) {
                return Err(tape.error(*p, "null"));
            }
        }
        ArrayDataBuilder::new(DataType::Null).len(pos.len()).build()
    }
}