git-whose-tree.go

package main

import (
	"flag"
	"fmt"
	"log"
	"os"

	git "gopkg.in/libgit2/git2go.v26"
)

func main() {
	log.SetPrefix("git-whose-tree: ")
	log.SetFlags(0)

	pwd, err := os.Getwd()
	check(err)

	repo, err := git.OpenRepositoryExtended(pwd, 0, "")
	check(err)

	flag.Parse()

	var trees []*git.Tree
	for _, s := range flag.Args() {
		oid, err := git.NewOid(s)
		check(err)
		tree, err := repo.LookupTree(oid)
		check(err)
		trees = append(trees, tree)
	}

	rw, err := repo.Walk()
	check(err)

	// Add all known refs.
	refiter, err := repo.NewReferenceIterator()
	check(err)
	for {
		ref, err := refiter.Next()
		if git.IsErrorCode(err, git.ErrIterOver) {
			break
		}
		// fmt.Printf("ref: %v\n", ref)
		rw.Push(ref.Target())
	}

	err = rw.Iterate(func(commit *git.Commit) bool {
		t, err := commit.Tree()
		check(err)
		for _, tree := range trees {
			if t.Id().Equal(tree.Id()) {
				fmt.Printf("tree %v -> commit %v\n", tree.Id(), commit.Id())
			}
		}
		return true
	})
	check(err)
}

func check(err error) {
	if err != nil {
		log.Fatal(err)
	}
}