diffx-core 0.7.1

Core library for diffx - blazing fast semantic diff engine for structured data. Zero-copy parsing, streaming support, memory-efficient algorithms
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153

// Array diff functions

use super::diff_recursive;
use crate::{DiffOptions, DiffResult};
use serde_json::Value;
use std::collections::HashMap;

pub(crate) fn diff_arrays(
    old_arr: &[Value],
    new_arr: &[Value],
    path: &str,
    results: &mut Vec<DiffResult>,
    options: &DiffOptions,
) {
    if let Some(id_key) = &options.array_id_key {
        diff_arrays_with_id(old_arr, new_arr, path, results, options, id_key);
    } else {
        diff_arrays_by_index(old_arr, new_arr, path, results, options);
    }
}

fn diff_arrays_with_id(
    old_arr: &[Value],
    new_arr: &[Value],
    path: &str,
    results: &mut Vec<DiffResult>,
    options: &DiffOptions,
    id_key: &str,
) {
    let mut old_by_id: HashMap<String, (usize, &Value)> = HashMap::new();
    let mut new_by_id: HashMap<String, (usize, &Value)> = HashMap::new();
    let mut old_without_id: Vec<(usize, &Value)> = Vec::new();
    let mut new_without_id: Vec<(usize, &Value)> = Vec::new();

    // Separate items with IDs from those without
    for (index, item) in old_arr.iter().enumerate() {
        if let Some(id_value) = item.get(id_key) {
            let id_str = match id_value {
                Value::String(s) => format!("\"{s}\""), // Add quotes for strings
                Value::Number(n) => n.to_string(),
                Value::Bool(b) => b.to_string(),
                _ => format!("{id_value:?}"),
            };
            old_by_id.insert(id_str, (index, item));
        } else {
            old_without_id.push((index, item));
        }
    }

    for (index, item) in new_arr.iter().enumerate() {
        if let Some(id_value) = item.get(id_key) {
            let id_str = match id_value {
                Value::String(s) => format!("\"{s}\""), // Add quotes for strings
                Value::Number(n) => n.to_string(),
                Value::Bool(b) => b.to_string(),
                _ => format!("{id_value:?}"),
            };
            new_by_id.insert(id_str, (index, item));
        } else {
            new_without_id.push((index, item));
        }
    }

    // Handle items with IDs
    // Find removed items
    for (id, (_, old_item)) in &old_by_id {
        if !new_by_id.contains_key(id) {
            let item_path = if path.is_empty() {
                format!("[{id_key}={id}]")
            } else {
                format!("{path}[{id_key}={id}]")
            };
            results.push(DiffResult::Removed(item_path, (*old_item).clone()));
        }
    }

    // Find added and modified items with IDs
    for (id, (_, new_item)) in &new_by_id {
        let item_path = if path.is_empty() {
            format!("[{id_key}={id}]")
        } else {
            format!("{path}[{id_key}={id}]")
        };

        match old_by_id.get(id) {
            None => {
                results.push(DiffResult::Added(item_path, (*new_item).clone()));
            }
            Some((_, old_item)) => {
                diff_recursive(old_item, new_item, &item_path, results, options);
            }
        }
    }

    // Handle items without IDs by index
    let max_len = old_without_id.len().max(new_without_id.len());
    for i in 0..max_len {
        match (old_without_id.get(i), new_without_id.get(i)) {
            (Some((old_index, old_item)), Some((_, new_item))) => {
                let item_path = if path.is_empty() {
                    format!("[{old_index}]")
                } else {
                    format!("{path}[{old_index}]")
                };
                diff_recursive(old_item, new_item, &item_path, results, options);
            }
            (Some((old_index, old_item)), None) => {
                let item_path = if path.is_empty() {
                    format!("[{old_index}]")
                } else {
                    format!("{path}[{old_index}]")
                };
                results.push(DiffResult::Removed(item_path, (*old_item).clone()));
            }
            (None, Some((new_index, new_item))) => {
                let item_path = if path.is_empty() {
                    format!("[{new_index}]")
                } else {
                    format!("{path}[{new_index}]")
                };
                results.push(DiffResult::Added(item_path, (*new_item).clone()));
            }
            (None, None) => unreachable!(),
        }
    }
}

fn diff_arrays_by_index(
    old_arr: &[Value],
    new_arr: &[Value],
    path: &str,
    results: &mut Vec<DiffResult>,
    options: &DiffOptions,
) {
    let max_len = old_arr.len().max(new_arr.len());

    for i in 0..max_len {
        let item_path = format!("{path}[{i}]");

        match (old_arr.get(i), new_arr.get(i)) {
            (Some(old_item), Some(new_item)) => {
                diff_recursive(old_item, new_item, &item_path, results, options);
            }
            (Some(old_item), None) => {
                results.push(DiffResult::Removed(item_path, old_item.clone()));
            }
            (None, Some(new_item)) => {
                results.push(DiffResult::Added(item_path, new_item.clone()));
            }
            (None, None) => unreachable!(),
        }
    }
}