helper/schema: if no ID is set then return nil

helper/schema/resource.go

@@ -108,7 +108,7 @@ func (r *Resource) Refresh(
 
 	err = r.Read(data, meta)
 	state := data.State()
-	if state.ID == "" {
+	if state != nil && state.ID == "" {
 		state = nil
 	}
 

helper/schema/resource_data.go

@@ -141,6 +141,13 @@ func (d *ResourceData) SetDependencies(ds []terraform.ResourceDependency) {
 func (d *ResourceData) State() *terraform.ResourceState {
 	var result terraform.ResourceState
 	result.ID = d.Id()
+
+	// If we have no ID, then this resource doesn't exist and we just
+	// return nil.
+	if result.ID == "" {
+		return nil
+	}
+
 	result.Attributes = d.stateObject("", d.schema)
 	result.ConnInfo = d.ConnInfo()
 	result.Dependencies = d.Dependencies()

helper/schema/resource_data_test.go

@@ -1524,7 +1524,21 @@ func TestResourceDataState(t *testing.T) {
 			}
 		}
 
+		// Set an ID so that the state returned is not nil
+		idSet := false
+		if d.Id() == "" {
+			idSet = true
+			d.SetId("foo")
+		}
+
 		actual := d.State()
+
+		// If we set an ID, then undo what we did so the comparison works
+		if actual != nil && idSet {
+			actual.ID = ""
+			delete(actual.Attributes, "id")
+		}
+
 		if !reflect.DeepEqual(actual, tc.Result) {
 			t.Fatalf("Bad: %d\n\n%#v", i, actual)
 		}
@@ -1533,6 +1547,7 @@ func TestResourceDataState(t *testing.T) {
 
 func TestResourceDataSetConnInfo(t *testing.T) {
 	d := &ResourceData{}
+	d.SetId("foo")
 	d.SetConnInfo(map[string]string{
 		"foo": "bar",
 	})
@@ -1549,6 +1564,7 @@ func TestResourceDataSetConnInfo(t *testing.T) {
 
 func TestResourceDataSetDependencies(t *testing.T) {
 	d := &ResourceData{}
+	d.SetId("foo")
 	d.SetDependencies([]terraform.ResourceDependency{
 		terraform.ResourceDependency{ID: "foo"},
 	})
@@ -1580,7 +1596,7 @@ func TestResourceDataSetId_clear(t *testing.T) {
 	d.SetId("")
 
 	actual := d.State()
-	if actual.ID != "" {
+	if actual != nil {
 		t.Fatalf("bad: %#v", actual)
 	}
 }