graph

node1 := NewNode("node1", "node2")
node2 := NewNode("node2", "node3")
node3 := NewNode("node3", "node1")
var g Graph
g = append(g, node1, node2, node3)
g, err := Resolve(g)
if err != nil {
	fmt.Println(err)
	// g.Display()
	return
}
fmt.Println("OK")

Output:

Circular dependency found

node1 := NewNode("node1", "node2")
node2 := NewNode("node2", "node3")
node3 := NewNode("node3")
var g Graph
g = append(g, node1, node2, node3)
g, err := Resolve(g)
if err != nil {
	fmt.Println(err)
	g.Display()
	return
}
fmt.Println("OK")
g.Display()

Output:

OK
node3
node2 -> node3
node1 -> node2