From 2caeb6192a4312e3d8e45b40e0a77ef8ac0d1ce9 Mon Sep 17 00:00:00 2001
From: Nishant Totla <nishanttotla@gmail.com>
Date: Fri, 11 Nov 2016 12:07:27 -0800
Subject: [PATCH] Adding utility functions - IsNameOnly and WithDefaultTag

Signed-off-by: Nishant Totla <nishanttotla@gmail.com>
---
 reference/helpers.go   | 12 ++++++++++++
 reference/normalize.go | 22 ++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 reference/helpers.go
 create mode 100644 reference/normalize.go

diff --git a/reference/helpers.go b/reference/helpers.go
new file mode 100644
index 00000000..dd7ee0ea
--- /dev/null
+++ b/reference/helpers.go
@@ -0,0 +1,12 @@
+package reference
+
+// IsNameOnly returns true if reference only contains a repo name.
+func IsNameOnly(ref Named) bool {
+	if _, ok := ref.(NamedTagged); ok {
+		return false
+	}
+	if _, ok := ref.(Canonical); ok {
+		return false
+	}
+	return true
+}
diff --git a/reference/normalize.go b/reference/normalize.go
new file mode 100644
index 00000000..b19a34e3
--- /dev/null
+++ b/reference/normalize.go
@@ -0,0 +1,22 @@
+package reference
+
+var (
+	defaultTag = "latest"
+)
+
+// EnsureTagged adds the default tag "latest" to a reference if it only has
+// a repo name.
+func EnsureTagged(ref Named) NamedTagged {
+	namedTagged, ok := ref.(NamedTagged)
+	if !ok {
+		namedTagged, err := WithTag(ref, defaultTag)
+		if err != nil {
+			// Default tag must be valid, to create a NamedTagged
+			// type with non-validated input the WithTag function
+			// should be used instead
+			panic(err)
+		}
+		return namedTagged
+	}
+	return namedTagged
+}