terraform: State.IsEmpty

terraform/state.go

@@ -125,6 +125,15 @@ func (s *State) ModuleOrphans(path []string, c *config.Config) [][]string {
 	return orphans
 }
 
+// Empty returns true if the state is empty.
+func (s *State) Empty() bool {
+	if s == nil {
+		return true
+	}
+
+	return len(s.Modules) == 0
+}
+
 // IsRemote returns true if State represents a state that exists and is
 // remote.
 func (s *State) IsRemote() bool {
@@ -282,7 +291,7 @@ func (r *RemoteState) deepcopy() *RemoteState {
 }
 
 func (r *RemoteState) Empty() bool {
-	return r.Type == "" && len(r.Config) == 0
+	return r == nil || r.Type == ""
 }
 
 func (r *RemoteState) Equals(other *RemoteState) bool {

terraform/state_test.go

@@ -312,6 +312,42 @@ func TestInstanceStateEqual(t *testing.T) {
 	}
 }
 
+func TestStateEmpty(t *testing.T) {
+	cases := []struct {
+		In     *State
+		Result bool
+	}{
+		{
+			nil,
+			true,
+		},
+		{
+			&State{},
+			true,
+		},
+		{
+			&State{
+				Remote: &RemoteState{Type: "foo"},
+			},
+			true,
+		},
+		{
+			&State{
+				Modules: []*ModuleState{
+					&ModuleState{},
+				},
+			},
+			false,
+		},
+	}
+
+	for i, tc := range cases {
+		if tc.In.Empty() != tc.Result {
+			t.Fatalf("bad %d %#v:\n\n%#v", i, tc.Result, tc.In)
+		}
+	}
+}
+
 func TestStateIsRemote(t *testing.T) {
 	cases := []struct {
 		In     *State