rev_list/
rev_list.rs

1//! Walk commits reachable from `HEAD` using [`rev_list::rev_list`] and [`RevListOptions`].
2//!
3//! Run: `cargo run -p grit-lib --example rev_list`
4
5use grit_lib::objects::{serialize_commit, CommitData, ObjectKind};
6use grit_lib::refs;
7use grit_lib::repo::init_repository;
8use grit_lib::repo::Repository;
9use grit_lib::rev_list::{rev_list, OutputMode, RevListOptions};
10use grit_lib::write_tree::write_tree_from_index;
11
12fn make_initial_commit(repo: &Repository) -> grit_lib::error::Result<grit_lib::objects::ObjectId> {
13    use grit_lib::index::{Index, IndexEntry, MODE_REGULAR};
14
15    let blob_oid = repo.odb.write(ObjectKind::Blob, b"log line\n")?;
16    let path = b"file.txt".to_vec();
17    let entry = IndexEntry {
18        ctime_sec: 0,
19        ctime_nsec: 0,
20        mtime_sec: 0,
21        mtime_nsec: 0,
22        dev: 0,
23        ino: 0,
24        mode: MODE_REGULAR,
25        uid: 0,
26        gid: 0,
27        size: 0,
28        oid: blob_oid,
29        flags: (path.len().min(0xfff)) as u16,
30        flags_extended: None,
31        path,
32        base_index_pos: 0,
33    };
34    let mut index = Index::new();
35    index.add_or_replace(entry);
36    repo.write_index(&mut index)?;
37    let index = repo.load_index()?;
38    let tree_oid = write_tree_from_index(&repo.odb, &index, "")?;
39
40    let commit = CommitData {
41        tree: tree_oid,
42        parents: Vec::new(),
43        author: "Example <example@example.com> 1700000000 +0000".to_owned(),
44        committer: "Example <example@example.com> 1700000000 +0000".to_owned(),
45        author_raw: Vec::new(),
46        committer_raw: Vec::new(),
47        encoding: None,
48        message: "root\n".to_owned(),
49        raw_message: None,
50    };
51    let oid = repo
52        .odb
53        .write(ObjectKind::Commit, &serialize_commit(&commit))?;
54    refs::write_ref(&repo.git_dir, "refs/heads/main", &oid)?;
55    Ok(oid)
56}
57
58fn main() -> grit_lib::error::Result<()> {
59    let root = tempfile::tempdir()?;
60    let repo = init_repository(root.path(), false, "main", None, "files")?;
61    let _root_commit = make_initial_commit(&repo)?;
62
63    let mut opts = RevListOptions::default();
64    opts.output_mode = OutputMode::OidOnly;
65    let result = rev_list(&repo, &[String::from("HEAD")], &[], &opts)?;
66
67    println!("commits from HEAD (oldest-first internal order may vary):");
68    for oid in &result.commits {
69        println!("  {oid}");
70    }
71
72    Ok(())
73}
rev_list/rev_list.rs

rev_list/
rev_list.rs
