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

#![cfg_attr(test, deny(warnings))]

use std::sync::Arc;

use dashmap::DashMap;
use swc_atoms::atom;
use swc_common::{
    comments::{Comment, CommentKind, Comments},
    BytePos, DUMMY_SP,
};

type CommentMap = Arc<DashMap<BytePos, Vec<Comment>, ahash::RandomState>>;

/// Multi-threaded implementation of [Comments]
#[derive(Clone, Default)]
pub struct SwcComments {
    pub leading: CommentMap,
    pub trailing: CommentMap,
}

impl Comments for SwcComments {
    fn add_leading(&self, pos: BytePos, cmt: Comment) {
        self.leading.entry(pos).or_default().push(cmt);
    }

    fn add_leading_comments(&self, pos: BytePos, comments: Vec<Comment>) {
        self.leading.entry(pos).or_default().extend(comments);
    }

    fn has_leading(&self, pos: BytePos) -> bool {
        if let Some(v) = self.leading.get(&pos) {
            !v.is_empty()
        } else {
            false
        }
    }

    fn move_leading(&self, from: BytePos, to: BytePos) {
        let cmt = self.take_leading(from);

        if let Some(mut cmt) = cmt {
            if from < to && self.has_leading(to) {
                cmt.extend(self.take_leading(to).unwrap());
            }

            self.add_leading_comments(to, cmt);
        }
    }

    fn take_leading(&self, pos: BytePos) -> Option<Vec<Comment>> {
        self.leading.remove(&pos).map(|v| v.1)
    }

    fn get_leading(&self, pos: BytePos) -> Option<Vec<Comment>> {
        self.leading.get(&pos).map(|v| v.to_owned())
    }

    fn add_trailing(&self, pos: BytePos, cmt: Comment) {
        self.trailing.entry(pos).or_default().push(cmt)
    }

    fn add_trailing_comments(&self, pos: BytePos, comments: Vec<Comment>) {
        self.trailing.entry(pos).or_default().extend(comments)
    }

    fn has_trailing(&self, pos: BytePos) -> bool {
        if let Some(v) = self.trailing.get(&pos) {
            !v.is_empty()
        } else {
            false
        }
    }

    fn move_trailing(&self, from: BytePos, to: BytePos) {
        let cmt = self.take_trailing(from);

        if let Some(mut cmt) = cmt {
            if from < to && self.has_trailing(to) {
                cmt.extend(self.take_trailing(to).unwrap());
            }

            self.add_trailing_comments(to, cmt);
        }
    }

    fn take_trailing(&self, pos: BytePos) -> Option<Vec<Comment>> {
        self.trailing.remove(&pos).map(|v| v.1)
    }

    fn get_trailing(&self, pos: BytePos) -> Option<Vec<Comment>> {
        self.trailing.get(&pos).map(|v| v.to_owned())
    }

    fn add_pure_comment(&self, pos: BytePos) {
        let mut leading = self.leading.entry(pos).or_default();
        let pure_comment = Comment {
            kind: CommentKind::Block,
            span: DUMMY_SP,
            text: atom!("#__PURE__"),
        };

        if !leading.iter().any(|c| c.text == pure_comment.text) {
            leading.push(pure_comment);
        }
    }

    fn with_leading<F, Ret>(&self, pos: BytePos, f: F) -> Ret
    where
        Self: Sized,
        F: FnOnce(&[Comment]) -> Ret,
    {
        let ret = if let Some(cmts) = self.leading.get(&pos) {
            f(&cmts)
        } else {
            f(&[])
        };

        ret
    }

    fn with_trailing<F, Ret>(&self, pos: BytePos, f: F) -> Ret
    where
        Self: Sized,
        F: FnOnce(&[Comment]) -> Ret,
    {
        let ret = if let Some(cmts) = &self.trailing.get(&pos) {
            f(cmts)
        } else {
            f(&[])
        };

        ret
    }
}