nova_vm 1.0.0

Nova Virtual Machine
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

// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at https://mozilla.org/MPL/2.0/.

use crate::{
    ecmascript::{Agent, OrdinaryObject, PromiseReaction, Value, new_promise_reaction_job},
    engine::{NoGcScope, bindable_handle},
    heap::{CompactionLists, HeapMarkAndSweep, WorkQueues},
};

#[derive(Debug, Clone, Default)]
pub(crate) struct PromiseHeapData<'a> {
    pub(crate) object_index: Option<OrdinaryObject<'a>>,
    pub(crate) promise_state: PromiseState<'a>,
}
bindable_handle!(PromiseHeapData);

#[derive(Debug, Clone)]
pub(crate) enum PromiseState<'a> {
    Pending {
        fulfill_reactions: Option<PromiseReactions<'a>>,
        reject_reactions: Option<PromiseReactions<'a>>,
        /// True if the resolution state of this promise depends on another
        /// promise or thenable that hasn't fulfilled or rejected yet.
        is_resolved: bool,
    },
    Fulfilled {
        promise_result: Value<'a>,
    },
    Rejected {
        promise_result: Value<'a>,
        is_handled: bool,
    },
}

impl Default for PromiseState<'_> {
    fn default() -> Self {
        Self::Pending {
            fulfill_reactions: None,
            reject_reactions: None,
            is_resolved: false,
        }
    }
}

#[derive(Debug, Clone)]
pub(crate) enum PromiseReactions<'a> {
    One(PromiseReaction<'a>),
    Many(Vec<PromiseReaction<'a>>),
}

impl PromiseReactions<'_> {
    /// ### [27.2.1.8 TriggerPromiseReactions ( reactions, argument )](https://tc39.es/ecma262/#sec-triggerpromisereactions)
    pub(crate) fn trigger(&self, agent: &mut Agent, argument: Value, gc: NoGcScope) {
        match self {
            PromiseReactions::One(reaction) => {
                let job = new_promise_reaction_job(agent, *reaction, argument, gc);
                agent.host_hooks.enqueue_promise_job(job);
            }
            PromiseReactions::Many(vec) => {
                for reaction in vec {
                    let job = new_promise_reaction_job(agent, *reaction, argument, gc);
                    agent.host_hooks.enqueue_promise_job(job);
                }
            }
        };
    }
}

impl HeapMarkAndSweep for PromiseReactions<'static> {
    fn mark_values(&self, queues: &mut WorkQueues) {
        match self {
            PromiseReactions::One(reaction) => reaction.mark_values(queues),
            PromiseReactions::Many(reactions) => reactions
                .iter()
                .for_each(|reaction| reaction.mark_values(queues)),
        }
    }

    fn sweep_values(&mut self, compactions: &CompactionLists) {
        match self {
            PromiseReactions::One(reaction) => reaction.sweep_values(compactions),
            PromiseReactions::Many(reactions) => reactions
                .iter_mut()
                .for_each(|reaction| reaction.sweep_values(compactions)),
        }
    }
}

impl HeapMarkAndSweep for PromiseHeapData<'static> {
    fn mark_values(&self, queues: &mut WorkQueues) {
        let Self {
            object_index,
            promise_state,
        } = self;
        object_index.mark_values(queues);
        promise_state.mark_values(queues);
    }

    fn sweep_values(&mut self, compactions: &CompactionLists) {
        let Self {
            object_index,
            promise_state,
        } = self;
        object_index.sweep_values(compactions);
        promise_state.sweep_values(compactions);
    }
}

impl HeapMarkAndSweep for PromiseState<'static> {
    fn mark_values(&self, queues: &mut WorkQueues) {
        match self {
            PromiseState::Pending {
                fulfill_reactions,
                reject_reactions,
                is_resolved: _,
            } => {
                fulfill_reactions.mark_values(queues);
                reject_reactions.mark_values(queues);
            }
            PromiseState::Fulfilled { promise_result }
            | PromiseState::Rejected {
                promise_result,
                is_handled: _,
            } => {
                promise_result.mark_values(queues);
            }
        }
    }

    fn sweep_values(&mut self, compactions: &CompactionLists) {
        match self {
            PromiseState::Pending {
                fulfill_reactions,
                reject_reactions,
                is_resolved: _,
            } => {
                fulfill_reactions.sweep_values(compactions);
                reject_reactions.sweep_values(compactions);
            }
            PromiseState::Fulfilled { promise_result }
            | PromiseState::Rejected {
                promise_result,
                is_handled: _,
            } => {
                promise_result.sweep_values(compactions);
            }
        }
    }
}