extract common into common.go

commits/common.go

@@ -0,0 +1,30 @@
+package commits
+
+import (
+	"errors"
+	"os"
+
+	git "github.com/go-git/go-git/v5"
+
+	"github.com/taigrr/gico/types"
+)
+
+type (
+	Repo      git.Repository
+	CommitSet struct {
+		Commits []types.Commit
+		Year    int
+	}
+)
+
+func OpenRepo(directory string) (Repo, error) {
+	if s, err := os.Stat(directory); err != nil {
+		return Repo{}, err
+	} else {
+		if !s.IsDir() {
+			return Repo{}, errors.New("received path to non-directory for git repo")
+		}
+	}
+	r, err := git.PlainOpenWithOptions(directory, &(git.PlainOpenOptions{DetectDotGit: true}))
+	return Repo(*r), err
+}