-Xnew-apply to enable the new apply graph

.travis.yml

@@ -10,6 +10,7 @@ install:
 - bash scripts/gogetcookie.sh
 script:
 - make test vet
+- make test TEST=./terraform TESTARGS=-Xnew-apply
 branches:
   only:
   - master

command/meta.go

@@ -328,6 +328,9 @@ func (m *Meta) flagSet(n string) *flag.FlagSet {
 		f.Var((*FlagKVFile)(&m.autoVariables), m.autoKey, "variable file")
 	}
 
+	// Experimental features
+	f.BoolVar(&terraform.X_newApply, "Xnew-apply", false, "experiment: new apply")
+
 	// Create an io.Writer that writes to our Ui properly for errors.
 	// This is kind of a hack, but it does the job. Basically: create
 	// a pipe, use a scanner to break it into lines, and output each line

terraform/context.go

@@ -17,9 +17,14 @@ import (
 // is called on Context.
 type InputMode byte
 
+// Variables prefixed with X_ are experimental features. They can be enabled
+// by setting them to true. This should be done before any API is called.
+// These should be expected to be removed at some point in the future; each
+// option should mention a schedule.
 var (
-	// NOTE: Internal only to toggle between the new and old apply graph
-	newApplyGraph = true
+	// X_newApply will enable the new apply graph. This will be removed
+	// and be on by default in 0.8.0.
+	X_newApply = false
 )
 
 const (
@@ -363,7 +368,7 @@ func (c *Context) Apply() (*State, error) {
 	// our new graph builder.
 	var graph *Graph
 	var err error
-	if c.destroy || !newApplyGraph {
+	if c.destroy || !X_newApply {
 		graph, err = c.Graph(&ContextGraphOpts{Validate: true})
 	} else {
 		graph, err = (&ApplyGraphBuilder{

terraform/terraform_test.go

@@ -22,8 +22,17 @@ import (
 const fixtureDir = "./test-fixtures"
 
 func TestMain(m *testing.M) {
+	// Experimental features
+	xNewApply := flag.Bool("Xnew-apply", false, "Experiment: new apply graph")
+
 	flag.Parse()
 
+	// Setup experimental features
+	X_newApply = *xNewApply
+	if X_newApply {
+		println("Xnew-apply enabled")
+	}
+
 	if testing.Verbose() {
 		// if we're verbose, use the logging requested by TF_LOG
 		logging.SetOutput()