Add resource id set.

api/resource/idset_test.go

@@ -0,0 +1,32 @@
+// Copyright 2020 The Kubernetes Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package resource_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	. "sigs.k8s.io/kustomize/api/resource"
+)
+
+func TestIdSet_Empty(t *testing.T) {
+	s := MakeIdSet([]*Resource{})
+	assert.Equal(t, 0, s.Size())
+	assert.False(t, s.Contains(testDeployment.CurId()))
+	assert.False(t, s.Contains(testConfigMap.CurId()))
+}
+
+func TestIdSet_One(t *testing.T) {
+	s := MakeIdSet([]*Resource{testDeployment})
+	assert.Equal(t, 1, s.Size())
+	assert.True(t, s.Contains(testDeployment.CurId()))
+	assert.False(t, s.Contains(testConfigMap.CurId()))
+}
+
+func TestIdSet_Two(t *testing.T) {
+	s := MakeIdSet([]*Resource{testDeployment, testConfigMap})
+	assert.Equal(t, 2, s.Size())
+	assert.True(t, s.Contains(testDeployment.CurId()))
+	assert.True(t, s.Contains(testConfigMap.CurId()))
+}