ref/refname: Add refname validation

1 files changed, 21 insertions, 0 deletions

diff --git a/ref/refname/root.go b/ref/refname/root.go
new file mode 100644
index 00000000..43361846
--- /dev/null
+++ b/ref/refname/root.go
@@ -0,0 +1,21 @@
+package refname
+
+import "strings"
+
+// IsRoot reports whether name is one root ref according to Git.
+func IsRoot(name string) bool {
+	if !IsRootSyntax(name) || IsPseudo(name) {
+		return false
+	}
+
+	if strings.HasSuffix(name, "_HEAD") {
+		return true
+	}
+
+	switch name {
+	case "HEAD", "AUTO_MERGE", "BISECT_EXPECTED_REV", "NOTES_MERGE_PARTIAL", "NOTES_MERGE_REF", "MERGE_AUTOSTASH":
+		return true
+	default:
+		return false
+	}
+}