terraform: fix outputs on destroy

terraform/context_test.go

@@ -3839,7 +3839,6 @@ func TestContext2Apply_destroy(t *testing.T) {
 	}
 }
 
-/*
 func TestContext2Apply_destroyOutputs(t *testing.T) {
 	m := testModule(t, "apply-destroy-outputs")
 	h := new(HookRecordApplyOrder)
@@ -3880,7 +3879,6 @@ func TestContext2Apply_destroyOutputs(t *testing.T) {
 		t.Fatalf("bad: %#v", mod)
 	}
 }
-*/
 
 func TestContext2Apply_destroyOrphan(t *testing.T) {
 	m := testModule(t, "apply-error")

terraform/eval_output.go

@@ -10,17 +10,20 @@ import (
 // for the given name to the current state.
 type EvalWriteOutput struct {
 	Name  string
-	Value EvalNode
+	Value *config.RawConfig
 }
 
 func (n *EvalWriteOutput) Args() ([]EvalNode, []EvalType) {
-	return []EvalNode{n.Value}, []EvalType{EvalTypeConfig}
+	return nil, nil
 }
 
 // TODO: test
 func (n *EvalWriteOutput) Eval(
 	ctx EvalContext, args []interface{}) (interface{}, error) {
-	cfg := args[0].(*ResourceConfig)
+	cfg, err := ctx.Interpolate(n.Value, nil)
+	if err != nil {
+		// Ignore it
+	}
 
 	state, lock := ctx.State()
 	if state == nil {
@@ -38,13 +41,17 @@ func (n *EvalWriteOutput) Eval(
 	}
 
 	// Get the value from the config
-	valueRaw, ok := cfg.Get("value")
+	var valueRaw interface{} = config.UnknownVariableValue
+	if cfg != nil {
+		var ok bool
+		valueRaw, ok = cfg.Get("value")
 		if !ok {
 			valueRaw = ""
 		}
 		if cfg.IsComputed("value") {
 			valueRaw = config.UnknownVariableValue
 		}
+	}
 
 	// If it is a list of values, get the first one
 	if list, ok := valueRaw.([]interface{}); ok {

terraform/graph_config_node.go

@@ -124,9 +124,13 @@ func (n *GraphNodeConfigOutput) DependentOn() []string {
 func (n *GraphNodeConfigOutput) EvalTree() EvalNode {
 	return &EvalOpFilter{
 		Ops: []walkOperation{walkRefresh, walkPlan, walkApply},
-		Node: &EvalWriteOutput{
+		Node: &EvalSequence{
+			Nodes: []EvalNode{
+				&EvalWriteOutput{
 					Name:  n.Output.Name,
-			Value: &EvalInterpolate{Config: n.Output.RawConfig},
+					Value: n.Output.RawConfig,
+				},
+			},
 		},
 	}
 }