oxi-tui 0.26.1

Terminal UI widgets and theme system for oxi, built on ratatui
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

//! Line diff algorithm for differential rendering.
//!
//! Compares two frame buffers at the row level and identifies changed rows.

/// Result of comparing two frame buffers.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct DiffResult {
    /// Index of the first row that changed (inclusive).
    pub first_changed: usize,
    /// Index of the last row that changed (inclusive).
    pub last_changed: usize,
}

/// Find the range of changed rows between two buffers.
///
/// Returns `None` if the buffers are identical (no changes).
/// Returns `Some(DiffResult)` with the inclusive range of changed rows.
pub fn find_changed_rows(
    prev: &[Vec<(char, u32, u32, u16)>],
    curr: &[Vec<(char, u32, u32, u16)>],
) -> Option<DiffResult> {
    let max_rows = prev.len().max(curr.len());

    let mut first_changed = None;
    let mut last_changed = None;

    for row in 0..max_rows {
        let prev_row = prev.get(row);
        let curr_row = curr.get(row);

        match (prev_row, curr_row) {
            (Some(p), Some(c)) if p == c => continue,
            _ => {
                if first_changed.is_none() {
                    first_changed = Some(row);
                }
                last_changed = Some(row);
            }
        }
    }

    first_changed.map(|first| DiffResult {
        first_changed: first,
        last_changed: last_changed.unwrap_or(first),
    })
}

#[cfg(test)]
mod tests {
    use super::*;

    fn row(s: &str) -> Vec<(char, u32, u32, u16)> {
        s.chars().map(|c| (c, 0, 0, 0)).collect()
    }

    fn styled_row(s: &str, fg: u32) -> Vec<(char, u32, u32, u16)> {
        s.chars().map(|c| (c, fg, 0, 0)).collect()
    }

    #[test]
    fn test_no_changes() {
        let prev = vec![row("hello"), row("world")];
        let curr = vec![row("hello"), row("world")];
        assert_eq!(find_changed_rows(&prev, &curr), None);
    }

    #[test]
    fn test_first_row_changed() {
        let prev = vec![row("hello"), row("world")];
        let curr = vec![row("HELLO"), row("world")];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 0);
        assert_eq!(diff.last_changed, 0);
    }

    #[test]
    fn test_last_row_changed() {
        let prev = vec![row("hello"), row("world")];
        let curr = vec![row("hello"), row("WORLD")];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 1);
        assert_eq!(diff.last_changed, 1);
    }

    #[test]
    fn test_middle_row_changed() {
        let prev = vec![row("aaa"), row("bbb"), row("ccc")];
        let curr = vec![row("aaa"), row("BBB"), row("ccc")];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 1);
        assert_eq!(diff.last_changed, 1);
    }

    #[test]
    fn test_multiple_rows_changed() {
        let prev = vec![row("aaa"), row("bbb"), row("ccc")];
        let curr = vec![row("AAA"), row("BBB"), row("ccc")];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 0);
        assert_eq!(diff.last_changed, 1);
    }

    #[test]
    fn test_style_change_detected() {
        let prev = vec![styled_row("hello", 0)];
        let curr = vec![styled_row("hello", 1)];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 0);
    }

    #[test]
    fn test_buffer_grew() {
        let prev = vec![row("aaa")];
        let curr = vec![row("aaa"), row("bbb")];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 1);
        assert_eq!(diff.last_changed, 1);
    }

    #[test]
    fn test_buffer_shrunk() {
        let prev = vec![row("aaa"), row("bbb")];
        let curr = vec![row("aaa")];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 1);
        assert_eq!(diff.last_changed, 1);
    }

    #[test]
    fn test_empty_buffers() {
        let prev: Vec<Vec<(char, u32, u32, u16)>> = vec![];
        let curr: Vec<Vec<(char, u32, u32, u16)>> = vec![];
        assert_eq!(find_changed_rows(&prev, &curr), None);
    }

    #[test]
    fn test_prev_empty_curr_nonempty() {
        let prev: Vec<Vec<(char, u32, u32, u16)>> = vec![];
        let curr = vec![row("hello")];
        let diff = find_changed_rows(&prev, &curr).unwrap();
        assert_eq!(diff.first_changed, 0);
        assert_eq!(diff.last_changed, 0);
    }
}