terraform: MergeDiff removes removed attributes in diff

terraform/state.go

@@ -247,6 +247,10 @@ func (s *ResourceState) MergeDiff(d *ResourceDiff) *ResourceState {
 	}
 	if d != nil {
 		for k, diff := range d.Attributes {
+			if diff.NewRemoved {
+				delete(result.Attributes, k)
+				continue
+			}
 			if diff.NewComputed {
 				result.Attributes[k] = config.UnknownVariableValue
 				continue

terraform/state_test.go

@@ -13,6 +13,7 @@ func TestResourceState_MergeDiff(t *testing.T) {
 		ID: "foo",
 		Attributes: map[string]string{
 			"foo":  "bar",
+			"port": "8000",
 		},
 	}
 
@@ -31,6 +32,9 @@ func TestResourceState_MergeDiff(t *testing.T) {
 				New:         "foo",
 				NewComputed: true,
 			},
+			"port": &ResourceAttrDiff{
+				NewRemoved: true,
+			},
 		},
 	}