hex_patch/fuzzer/
fuzzer.rs

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pub fn fuzzy_search_cloned<T>(key: &str, entries: &[T]) -> Vec<T>
where
    T: AsRef<str> + Clone,
{
    let mut ret = entries.to_vec();
    fuzzy_search_in_place(key, &mut ret);
    ret
}

pub fn fuzzy_search_in_place<T>(key: &str, entries: &mut [T])
where
    T: AsRef<str> + Clone,
{
    entries.sort_by_cached_key(|source| -score(source.as_ref(), key));
}

fn score(source: &str, key: &str) -> isize {
    let mut score = 0;

    let char_found_bonus = 10;
    let key_char_not_found_penalty = -5;
    let self_char_not_found_penalty = -1;

    let mut key_chars = key.chars();
    let self_chars = source.chars();
    let mut current_key_char = key_chars.next();
    for self_char in self_chars {
        if let Some(key_char) = current_key_char {
            if self_char == key_char {
                score += char_found_bonus;
                current_key_char = key_chars.next();
            } else {
                score += self_char_not_found_penalty;
            }
        } else {
            break;
        }
    }
    for _ in key_chars {
        score += key_char_not_found_penalty;
    }
    score
}

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

    #[test]
    fn test_fuzzy_search() {
        let entries = vec!["abc", "def", "ghi", "jkl"];
        let result = fuzzy_search_cloned("d", &entries);
        assert_eq!(result, vec!["def", "abc", "ghi", "jkl"]);
    }
}