terraform: Adding flag for CreateBeforeDestroy

terraform/graph.go

@@ -557,6 +557,9 @@ func graphAddDiff(g *depgraph.Graph, d *ModuleDiff) error {
 					Target: newN,
 				})
 
+				// Set the CreateBeforeDestroy flag on the old noun
+				rn.Resource.Flags |= FlagCreateBeforeDestroy
+
 			} else {
 				dep := &depgraph.Dependency{
 					Name:   newN.Name,

terraform/graph_test.go

@@ -704,6 +704,12 @@ func TestGraphAddDiff_createBeforeDestroy(t *testing.T) {
 		t.Fatalf("bad:\n\n%s\n\nexpected:\n\n%s", actual, expected)
 	}
 
+	// Verify the flag is set
+	r := g.Noun("aws_instance.bar")
+	if r.Meta.(*GraphNodeResource).Resource.Flags&FlagCreateBeforeDestroy == 0 {
+		t.Fatalf("missing FlagCreateBeforeDestroy")
+	}
+
 	// Verify that our original structure has not been modified
 	diffHash2 := checksumStruct(t, diff)
 	if diffHash != diffHash2 {

terraform/resource.go

@@ -47,6 +47,7 @@ const (
 	FlagTainted
 	FlagOrphan
 	FlagHasTainted
+	FlagCreateBeforeDestroy
 )
 
 // InstanceInfo is used to hold information about the instance and/or