dimakudosh/difflib

Port of Python's difflib library to Rust

Difflib

Port of Python's difflib library to Rust. It's provide all necessary tools for comparing word sequences.

Installation

Simply add difflib to your dependencies block in Cargo.toml

[dependencies]
difflib = "0.4.0"

Documentation

Documentation is available at https://github.com/DimaKudosh/difflib/wiki

Example

extern crate difflib;

use difflib::differ::Differ;
use difflib::sequencematcher::SequenceMatcher;

fn main() {
    // unified_diff
    let first_text = "one two three four".split(" ").collect::<Vec<&str>>();
    let second_text = "zero one tree four".split(" ").collect::<Vec<&str>>();
    let diff = difflib::unified_diff(
        &first_text,
        &second_text,
        "Original",
        "Current",
        "2005-01-26 23:30:50",
        "2010-04-02 10:20:52",
        3,
    );
    for line in &diff {
        println!("{:?}", line);
    }

    //context_diff
    let diff = difflib::context_diff(
        &first_text,
        &second_text,
        "Original",
        "Current",
        "2005-01-26 23:30:50",
        "2010-04-02 10:20:52",
        3,
    );
    for line in &diff {
        println!("{:?}", line);
    }

    //get_close_matches
    let words = vec!["ape", "apple", "peach", "puppy"];
    let result = difflib::get_close_matches("appel", words, 3, 0.6);
    println!("{:?}", result);

    //Differ examples
    let differ = Differ::new();
    let diff = differ.compare(&first_text, &second_text);
    for line in &diff {
        println!("{:?}", line);
    }

    //SequenceMatcher examples
    let mut matcher = SequenceMatcher::new("one two three four", "zero one tree four");
    let m = matcher.find_longest_match(0, 18, 0, 18);
    println!("{:?}", m);
    let all_matches = matcher.get_matching_blocks();
    println!("{:?}", all_matches);
    let opcode = matcher.get_opcodes();
    println!("{:?}", opcode);
    let grouped_opcodes = matcher.get_grouped_opcodes(2);
    println!("{:?}", grouped_opcodes);
    let ratio = matcher.ratio();
    println!("{:?}", ratio);
    matcher.set_seqs("aaaaa", "aaaab");
    println!("{:?}", matcher.ratio());
}

difflib's Issues

vec vs set

In the sequencematcher the second_sequence_popular is a Vec; but in the Python difflib.py b_popular is a set which may explain why this rust difflib's behavior is different from the Python difflib's behavior.

Also, sequencematcher uses HashMap rather than FnvHashMap (and FnvHashSet for second_sequence_popular); these Fnv- versions should be faster.

Use of deprecated function

If the project is still maintained, the deprecated function .trim_right could be replaced by trim_end.

Roadmap discussion

Would you please say what's done and what still needs to be done?

Is GNU Diffutils the model to strive for feature parity? How do they compare?