1 files changed, 88 insertions, 0 deletions
diff --git a/git/git.go b/git/git.go
new file mode 100644
index 0000000..46ec357
--- /dev/null
+++ b/git/git.go
@@ -0,0 +1,88 @@
+package git
+
+import (
+	"fmt"
+
+	"github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/object"
+)
+
+func AllCommits(r *git.Repository) ([]*object.Commit, error) {
+	ci, err := r.Log(&git.LogOptions{All: true})
+	if err != nil {
+		return nil, fmt.Errorf("all commits: %w", err)
+	}
+
+	commits := []*object.Commit{}
+	ci.ForEach(func(c *object.Commit) error {
+		commits = append(commits, c)
+		return nil
+	})
+
+	return commits, nil
+}
+
+// A nicer git tree representation.
+type NiceTree struct {
+	Name   string
+	Mode   string
+	Size   int64
+	IsFile bool
+}
+
+func FilesAtHead(r *git.Repository, path string) ([]NiceTree, error) {
+	head, err := r.Head()
+	if err != nil {
+		return nil, fmt.Errorf("getting head: %w", err)
+	}
+
+	return FilesAtRef(r, head, path)
+}
+
+func FilesAtRef(r *git.Repository, ref *plumbing.Reference, path string) ([]NiceTree, error) {
+	c, err := r.CommitObject(ref.Hash())
+	if err != nil {
+		return nil, fmt.Errorf("commit object: %w", err)
+	}
+
+	files := []NiceTree{}
+	tree, err := c.Tree()
+	if err != nil {
+		return nil, fmt.Errorf("file tree: %w", err)
+	}
+
+	if path == "" {
+		files = makeNiceTree(tree.Entries)
+	} else {
+		o, err := tree.FindEntry(path)
+		if err != nil {
+			return nil, err
+		}
+
+		if !o.Mode.IsFile() {
+			subtree, err := tree.Tree(path)
+			if err != nil {
+				return nil, err
+			}
+
+			files = makeNiceTree(subtree.Entries)
+		}
+	}
+
+	return files, nil
+}
+
+func makeNiceTree(es []object.TreeEntry) []NiceTree {
+	nts := []NiceTree{}
+	for _, e := range es {
+		mode, _ := e.Mode.ToOSFileMode()
+		nts = append(nts, NiceTree{
+			Name:   e.Name,
+			Mode:   mode.String(),
+			IsFile: e.Mode.IsFile(),
+		})
+	}
+
+	return nts
+}