From d8474d5990dbcb9c748ee030ebafee2b49b8cf13 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mislav=20Marohni=C4=87?= <mislav@github.com>
Date: Fri, 10 Jan 2020 14:08:54 +0100
Subject: [PATCH] Read current git branch in a way that is compatible with
 older git

---
 git/git.go | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/git/git.go b/git/git.go
index 91664b118..fd3a1d963 100644
--- a/git/git.go
+++ b/git/git.go
@@ -18,11 +18,13 @@ func VerifyRef(ref string) bool {
 	return err == nil
 }
 
+// CurrentBranch reads the checked-out branch for the git repository
 func CurrentBranch() (string, error) {
-	branchCmd := exec.Command("git", "branch", "--show-current")
+	// we avoid using `git branch --show-current` for compatibility with git < 2.22
+	branchCmd := exec.Command("git", "rev-parse", "--abbrev-ref", "HEAD")
 	output, err := utils.PrepareCmd(branchCmd).Output()
 	branchName := firstLine(output)
-	if err == nil && branchName == "" {
+	if err == nil && branchName == "HEAD" {
 		return "", errors.New("git: not on any branch")
 	}
 	return branchName, err