arrow_data/equal/
structure.rs

1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements.  See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership.  The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License.  You may obtain a copy of the License at
8//
9//   http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied.  See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18use crate::data::{contains_nulls, ArrayData};
19
20use super::equal_range;
21
22/// Compares the values of two [ArrayData] starting at `lhs_start` and `rhs_start` respectively
23/// for `len` slots.
24fn equal_child_values(
25    lhs: &ArrayData,
26    rhs: &ArrayData,
27    lhs_start: usize,
28    rhs_start: usize,
29    len: usize,
30) -> bool {
31    lhs.child_data()
32        .iter()
33        .zip(rhs.child_data())
34        .all(|(lhs_values, rhs_values)| {
35            equal_range(lhs_values, rhs_values, lhs_start, rhs_start, len)
36        })
37}
38
39pub(super) fn struct_equal(
40    lhs: &ArrayData,
41    rhs: &ArrayData,
42    lhs_start: usize,
43    rhs_start: usize,
44    len: usize,
45) -> bool {
46    // Only checking one null mask here because by the time the control flow reaches
47    // this point, the equality of the two masks would have already been verified.
48    if !contains_nulls(lhs.nulls(), lhs_start, len) {
49        equal_child_values(lhs, rhs, lhs_start, rhs_start, len)
50    } else {
51        // get a ref of the null buffer bytes, to use in testing for nullness
52        let lhs_nulls = lhs.nulls().unwrap();
53        let rhs_nulls = rhs.nulls().unwrap();
54        // with nulls, we need to compare item by item whenever it is not null
55        (0..len).all(|i| {
56            let lhs_pos = lhs_start + i;
57            let rhs_pos = rhs_start + i;
58            // if both struct and child had no null buffers,
59            let lhs_is_null = lhs_nulls.is_null(lhs_pos);
60            let rhs_is_null = rhs_nulls.is_null(rhs_pos);
61
62            if lhs_is_null != rhs_is_null {
63                return false;
64            }
65
66            lhs_is_null || equal_child_values(lhs, rhs, lhs_pos, rhs_pos, 1)
67        })
68    }
69}
arrow_data/equal/structure.rs

arrow_data/equal/
structure.rs
