jsoncompat 0.3.0

JSON Schema Compatibility Checker
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 subset helpers.

use crate::SchemaNode;
use crate::subset::{SubschemaCheckContext, is_subschema_of_with_context};
use json_schema_ast::{ContainsConstraint, CountRange};
use serde_json::Value;

use super::scalar::check_enum_inclusion;

pub(super) struct ArrayConstraints<'a> {
    pub(super) prefix_items: &'a [SchemaNode],
    pub(super) items: &'a SchemaNode,
    pub(super) item_count: CountRange<u64>,
    pub(super) contains: Option<&'a ContainsConstraint<SchemaNode>>,
    pub(super) unique_items: bool,
    pub(super) enumeration: Option<&'a [Value]>,
}

pub(super) fn array_constraints_subsumed(
    sub: ArrayConstraints<'_>,
    sup: ArrayConstraints<'_>,
    context: &mut SubschemaCheckContext,
) -> bool {
    sup.item_count.contains_range(sub.item_count)
        && (!sup.unique_items
            || sub.unique_items
            || sub.item_count.max().is_some_and(|max_items| max_items <= 1))
        && array_item_constraints_subsumed(
            sub.prefix_items,
            sub.items,
            sub.item_count.max(),
            sup.prefix_items,
            sup.items,
            context,
        )
        && array_contains_constraints_subsumed(
            sub.prefix_items,
            sub.items,
            sub.item_count,
            sub.contains,
            sup.contains,
            context,
        )
        && check_enum_inclusion(sub.enumeration, sup.enumeration)
}

fn array_item_constraints_subsumed(
    sub_prefix_items: &[SchemaNode],
    sub_items: &SchemaNode,
    sub_max_items: Option<u64>,
    sup_prefix_items: &[SchemaNode],
    sup_items: &SchemaNode,
    context: &mut SubschemaCheckContext,
) -> bool {
    let checked_prefix_len = sub_prefix_items.len().max(sup_prefix_items.len());
    for index in 0..checked_prefix_len {
        if !array_index_can_exist(sub_max_items, index) {
            return true;
        }

        let sub_item = sub_prefix_items.get(index).unwrap_or(sub_items);
        let sup_item = sup_prefix_items.get(index).unwrap_or(sup_items);
        if !is_subschema_of_with_context(sub_item, sup_item, context) {
            return false;
        }
    }

    !array_index_can_exist(sub_max_items, checked_prefix_len)
        || is_subschema_of_with_context(sub_items, sup_items, context)
}

fn array_contains_constraints_subsumed(
    sub_prefix_items: &[SchemaNode],
    sub_items: &SchemaNode,
    sub_item_count: CountRange<u64>,
    sub_contains: Option<&ContainsConstraint<SchemaNode>>,
    sup_contains: Option<&ContainsConstraint<SchemaNode>>,
    context: &mut SubschemaCheckContext,
) -> bool {
    let Some(sup_contains) = sup_contains else {
        return true;
    };

    let sup_contains_count = sup_contains.count();
    let sub_max_items = sub_item_count.max();

    let lower_bound_ok = sup_contains_count.min() == 0
        || sub_contains.is_some_and(|sub_contains| {
            sub_contains.count().min() >= sup_contains_count.min()
                && is_subschema_of_with_context(&sub_contains.schema, &sup_contains.schema, context)
        })
        || (sub_item_count.min() >= sup_contains_count.min()
            && all_array_item_schemas_subsumed_by(
                sub_prefix_items,
                sub_items,
                sub_max_items,
                &sup_contains.schema,
                context,
            ));

    if !lower_bound_ok {
        return false;
    }

    let Some(sup_max_contains) = sup_contains_count.max() else {
        return true;
    };

    sub_contains
        .filter(|sub_contains| {
            sub_contains
                .count()
                .max()
                .is_some_and(|sub_max_contains| sub_max_contains <= sup_max_contains)
                && is_subschema_of_with_context(&sup_contains.schema, &sub_contains.schema, context)
        })
        .is_some()
        || (sub_max_items.is_some_and(|sub_max_items| sub_max_items <= sup_max_contains)
            && all_array_item_schemas_subsumed_by(
                sub_prefix_items,
                sub_items,
                sub_max_items,
                &sup_contains.schema,
                context,
            ))
}

fn all_array_item_schemas_subsumed_by(
    prefix_items: &[SchemaNode],
    items: &SchemaNode,
    max_items: Option<u64>,
    sup_schema: &SchemaNode,
    context: &mut SubschemaCheckContext,
) -> bool {
    for (index, prefix_item) in prefix_items.iter().enumerate() {
        if !array_index_can_exist(max_items, index) {
            return true;
        }
        if !is_subschema_of_with_context(prefix_item, sup_schema, context) {
            return false;
        }
    }

    !array_index_can_exist(max_items, prefix_items.len())
        || is_subschema_of_with_context(items, sup_schema, context)
}

fn array_index_can_exist(max_items: Option<u64>, index: usize) -> bool {
    let Ok(index) = u64::try_from(index) else {
        return false;
    };
    max_items.is_none_or(|max_items| index < max_items)
}