fluidattacks_core_git/
rebase.rs

1use anyhow::{bail, Result};
2
3use super::types::RebaseResult;
4use crate::cli;
5
6#[allow(clippy::too_many_arguments)]
7pub async fn rebase(
8    repo: &str,
9    file: &str,
10    line: usize,
11    rev_a: &str,
12    rev_b: &str,
13    similarity_threshold: f64,
14) -> Result<Option<RebaseResult>> {
15    if rev_a == rev_b {
16        return Ok(Some(RebaseResult {
17            path: file.to_owned(),
18            line,
19            rev: rev_b.to_owned(),
20        }));
21    }
22
23    let resolved_a = cli::get_head_commit(repo, rev_a)
24        .await
25        .unwrap_or_else(|_| rev_a.to_owned());
26    let resolved_b = cli::get_head_commit(repo, rev_b)
27        .await
28        .unwrap_or_else(|_| rev_b.to_owned());
29
30    let content_a = cli::show_file_at_rev(repo, &resolved_a, file).await?;
31    let Some(content_a) = content_a else {
32        return Ok(None);
33    };
34    let lines_a: Vec<&str> = content_a.lines().collect();
35    let anchor_text = get_anchor_line(&lines_a, line, rev_a)?;
36
37    let blame_result = get_blame_with_fallback(repo, file, line, &resolved_a, &resolved_b).await?;
38    let Some(blame_result) = blame_result else {
39        return Ok(None);
40    };
41
42    if blame_result.rev != resolved_b {
43        return Ok(None);
44    }
45
46    let target_file = if blame_result.path.is_empty() {
47        file.to_owned()
48    } else {
49        blame_result.path.clone()
50    };
51
52    let new_line = get_new_line(repo, &resolved_b, &target_file, blame_result.line).await?;
53    let Some(new_text) = new_line else {
54        return Ok(None);
55    };
56
57    let ratio = similarity_ratio(anchor_text, &new_text);
58    if ratio >= similarity_threshold {
59        Ok(Some(RebaseResult {
60            path: target_file,
61            line: blame_result.line,
62            rev: blame_result.rev,
63        }))
64    } else {
65        Ok(None)
66    }
67}
68
69async fn get_new_line(repo: &str, rev: &str, file: &str, line: usize) -> Result<Option<String>> {
70    let content = cli::show_file_at_rev(repo, rev, file).await?;
71    let Some(content) = content else {
72        return Ok(None);
73    };
74    let lines: Vec<&str> = content.lines().collect();
75    if line == 0 || line > lines.len() {
76        return Ok(None);
77    }
78    Ok(lines.get(line.saturating_sub(1)).map(|s| (*s).to_owned()))
79}
80
81fn get_anchor_line<'a>(lines: &[&'a str], line: usize, rev: &str) -> Result<&'a str> {
82    if line == 0 || line > lines.len() {
83        bail!(
84            "line {line} out of range (file has {} lines at {rev})",
85            lines.len()
86        );
87    }
88    lines
89        .get(line.saturating_sub(1))
90        .copied()
91        .ok_or_else(|| anyhow::anyhow!("line {line} out of range at {rev}"))
92}
93
94async fn get_blame_with_fallback(
95    repo: &str,
96    file: &str,
97    line: usize,
98    resolved_a: &str,
99    resolved_b: &str,
100) -> Result<Option<super::types::BlameResult>> {
101    let result = cli::blame_reverse(repo, file, line, resolved_a, resolved_b, false).await?;
102    if result.is_some() {
103        return Ok(result);
104    }
105    cli::blame_reverse(repo, file, line, resolved_a, resolved_b, true).await
106}
107
108#[must_use]
109#[allow(clippy::cast_precision_loss, clippy::as_conversions)]
110pub fn similarity_ratio(a: &str, b: &str) -> f64 {
111    use similar::ChangeTag;
112    let diff = similar::TextDiff::from_chars(a, b);
113    let matching: usize = diff
114        .iter_all_changes()
115        .filter(|c| c.tag() == ChangeTag::Equal)
116        .map(|c| c.value().len())
117        .sum();
118    let total = a.len().saturating_add(b.len());
119    if total == 0 {
120        return 1.0;
121    }
122    (2.0 * matching as f64) / total as f64
123}
124
125#[cfg(test)]
126mod tests {
127    use super::similarity_ratio;
128
129    #[test]
130    fn identical_strings() {
131        assert!((similarity_ratio("hello", "hello") - 1.0).abs() < f64::EPSILON);
132    }
133
134    #[test]
135    fn both_empty() {
136        assert!((similarity_ratio("", "") - 1.0).abs() < f64::EPSILON);
137    }
138
139    #[test]
140    fn completely_different() {
141        assert!(similarity_ratio("abc", "xyz") < 0.01);
142    }
143
144    #[test]
145    fn partial_match() {
146        let r = similarity_ratio("abcdef", "abcxyz");
147        assert!(r > 0.4 && r < 0.7, "ratio was {r}");
148    }
149
150    #[test]
151    fn one_empty_one_not() {
152        assert!((similarity_ratio("hello", "") - 0.0).abs() < f64::EPSILON);
153    }
154}
fluidattacks_core_git/rebase.rs

fluidattacks_core_git/
rebase.rs
