1 files changed, 37 insertions, 0 deletions

diff --git a/vendor/github.com/hashicorp/terraform/dag/edge.go b/vendor/github.com/hashicorp/terraform/dag/edge.go
new file mode 100644
index 0000000..f0d99ee
--- /dev/null
+++ b/vendor/github.com/hashicorp/terraform/dag/edge.go
@@ -0,0 +1,37 @@
+package dag
+
+import (
+        "fmt"
+)
+
+// Edge represents an edge in the graph, with a source and target vertex.
+type Edge interface {
+        Source() Vertex
+        Target() Vertex
+
+        Hashable
+}
+
+// BasicEdge returns an Edge implementation that simply tracks the source
+// and target given as-is.
+func BasicEdge(source, target Vertex) Edge {
+        return &basicEdge{S: source, T: target}
+}
+
+// basicEdge is a basic implementation of Edge that has the source and
+// target vertex.
+type basicEdge struct {
+        S, T Vertex
+}
+
+func (e *basicEdge) Hashcode() interface{} {
+        return fmt.Sprintf("%p-%p", e.S, e.T)
+}
+
+func (e *basicEdge) Source() Vertex {
+        return e.S
+}
+
+func (e *basicEdge) Target() Vertex {
+        return e.T
+}