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oak_python/highlighter/
mod.rs

1#[derive(Debug, Clone, Copy, PartialEq, Eq)]
2pub enum HighlightKind {
3    Keyword,
4    String,
5    Number,
6    Comment,
7    Identifier,
8    Decorator,
9}
10
11/// 高亮器 trait
12pub trait Highlighter {
13    /// 对给定的文本进行高亮处理
14    fn highlight(&self, text: &str) -> Vec<(usize, usize, HighlightKind)>;
15}
16
17pub struct PythonHighlighter {
18    pub use_parser: bool,
19}
20
21impl Default for PythonHighlighter {
22    fn default() -> Self {
23        Self { use_parser: false }
24    }
25}
26
27impl PythonHighlighter {
28    pub fn new() -> Self {
29        Self::default()
30    }
31
32    pub fn with_parser() -> Self {
33        Self { use_parser: true }
34    }
35
36    fn highlight_keywords(&self, text: &str) -> Vec<(usize, usize, HighlightKind)> {
37        let mut highlights = Vec::new();
38        let keywords = [
39            "False", "None", "True", "and", "as", "assert", "async", "await", "break", "class", "continue", "def", "del", "elif", "else", "except", "finally", "for", "from", "global", "if", "import", "in", "is", "lambda", "nonlocal", "not", "or", "pass",
40            "raise", "return", "try", "while", "with", "yield",
41        ];
42
43        for keyword in &keywords {
44            let mut start = 0;
45            while let Some(pos) = text[start..].find(keyword) {
46                let absolute_pos = start + pos;
47                let end_pos = absolute_pos + keyword.len();
48
49                let is_word_boundary_before = absolute_pos == 0 || !text.chars().nth(absolute_pos - 1).unwrap_or(' ').is_alphanumeric();
50                let is_word_boundary_after = end_pos >= text.len() || !text.chars().nth(end_pos).unwrap_or(' ').is_alphanumeric();
51
52                if is_word_boundary_before && is_word_boundary_after {
53                    highlights.push((absolute_pos, end_pos, HighlightKind::Keyword));
54                }
55
56                start = absolute_pos + 1;
57            }
58        }
59
60        highlights
61    }
62    fn highlight_strings(&self, text: &str) -> Vec<(usize, usize, HighlightKind)> {
63        let mut highlights = Vec::new();
64        let mut chars = text.char_indices().peekable();
65
66        while let Some((i, ch)) = chars.next() {
67            match ch {
68                '"' | '\'' => {
69                    let quote = ch;
70                    let start = i;
71                    let mut escaped = false;
72                    let mut found_end = false;
73
74                    while let Some((j, next_ch)) = chars.next() {
75                        if escaped {
76                            escaped = false;
77                        }
78                        else if next_ch == '\\' {
79                            escaped = true;
80                        }
81                        else if next_ch == quote {
82                            highlights.push((start, j + 1, HighlightKind::String));
83                            found_end = true;
84                            break;
85                        }
86                    }
87                    if !found_end {
88                        highlights.push((start, text.len(), HighlightKind::String));
89                    }
90                }
91                _ => {}
92            }
93        }
94        highlights
95    }
96
97    fn highlight_numbers(&self, text: &str) -> Vec<(usize, usize, HighlightKind)> {
98        let mut highlights = Vec::new();
99        let mut start = None;
100
101        for (i, ch) in text.char_indices() {
102            if ch.is_ascii_digit() {
103                if start.is_none() {
104                    start = Some(i);
105                }
106            }
107            else {
108                if let Some(s) = start {
109                    highlights.push((s, i, HighlightKind::Number));
110                    start = None;
111                }
112            }
113        }
114        if let Some(s) = start {
115            highlights.push((s, text.len(), HighlightKind::Number));
116        }
117        highlights
118    }
119
120    fn highlight_comments(&self, text: &str) -> Vec<(usize, usize, HighlightKind)> {
121        let mut highlights = Vec::new();
122        let mut start = 0;
123        while let Some(pos) = text[start..].find('#') {
124            let absolute_pos = start + pos;
125            let end_pos = text[absolute_pos..].find('\n').map(|n| absolute_pos + n).unwrap_or(text.len());
126            highlights.push((absolute_pos, end_pos, HighlightKind::Comment));
127            start = end_pos;
128        }
129        highlights
130    }
131}
132
133impl Highlighter for PythonHighlighter {
134    fn highlight(&self, text: &str) -> Vec<(usize, usize, HighlightKind)> {
135        let mut highlights = self.highlight_keywords(text);
136        highlights.extend(self.highlight_strings(text));
137        highlights.extend(self.highlight_numbers(text));
138        highlights.extend(self.highlight_comments(text));
139        highlights.sort_by_key(|h| h.0);
140        highlights
141    }
142}