Add unit test.

Signed-off-by: Random-Liu <lantaol@google.com>

pkg/server/image_pull_test.go

@@ -0,0 +1,74 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package server
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/kubernetes-incubator/cri-containerd/pkg/metadata"
+)
+
+func TestUpdateImageMetadata(t *testing.T) {
+	meta := metadata.ImageMetadata{
+		ID:      "test-id",
+		ChainID: "test-chain-id",
+		Size:    1234,
+	}
+	for desc, test := range map[string]struct {
+		repoTags            []string
+		repoDigests         []string
+		repoTag             string
+		repoDigest          string
+		expectedRepoTags    []string
+		expectedRepoDigests []string
+	}{
+		"Add duplicated repo tag and digest": {
+			repoTags:            []string{"a", "b"},
+			repoDigests:         []string{"c", "d"},
+			repoTag:             "a",
+			repoDigest:          "c",
+			expectedRepoTags:    []string{"a", "b"},
+			expectedRepoDigests: []string{"c", "d"},
+		},
+		"Add new repo tag and digest": {
+			repoTags:            []string{"a", "b"},
+			repoDigests:         []string{"c", "d"},
+			repoTag:             "e",
+			repoDigest:          "f",
+			expectedRepoTags:    []string{"a", "b", "e"},
+			expectedRepoDigests: []string{"c", "d", "f"},
+		},
+		"Add empty repo tag and digest": {
+			repoTags:            []string{"a", "b"},
+			repoDigests:         []string{"c", "d"},
+			repoTag:             "",
+			repoDigest:          "",
+			expectedRepoTags:    []string{"a", "b"},
+			expectedRepoDigests: []string{"c", "d"},
+		},
+	} {
+		t.Logf("TestCase %q", desc)
+		m := meta
+		m.RepoTags = test.repoTags
+		m.RepoDigests = test.repoDigests
+		updateImageMetadata(&m, test.repoTag, test.repoDigest)
+		assert.Equal(t, test.expectedRepoTags, m.RepoTags)
+		assert.Equal(t, test.expectedRepoDigests, m.RepoDigests)
+	}
+}