Add unit test.

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

pkg/server/version_test.go

@@ -0,0 +1,61 @@
+/*
+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 (
+	"errors"
+	"testing"
+
+	versionapi "github.com/containerd/containerd/api/services/version"
+	"github.com/golang/mock/gomock"
+	"github.com/golang/protobuf/ptypes/empty"
+	"github.com/stretchr/testify/assert"
+	"golang.org/x/net/context"
+	runtime "k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1"
+
+	servertesting "github.com/kubernetes-incubator/cri-containerd/pkg/server/testing"
+)
+
+func TestVersion(t *testing.T) {
+	ctrl := gomock.NewController(t)
+	defer ctrl.Finish()
+	// TODO(random-liu): Check containerd version after containerd fixes its version.
+	for desc, test := range map[string]struct {
+		versionRes *versionapi.VersionResponse
+		versionErr error
+		expectErr  bool
+	}{
+		"should return error if containerd version returns error": {
+			versionErr: errors.New("random error"),
+			expectErr:  true,
+		},
+		"should not return error if containerd version returns successfully": {
+			versionRes: &versionapi.VersionResponse{Version: "1.1.1"},
+			expectErr:  false,
+		},
+	} {
+		t.Logf("TestCase %q", desc)
+		c := newTestCRIContainerdService()
+		ctx := context.Background()
+		mock := servertesting.NewMockVersionClient(ctrl)
+		mock.EXPECT().Version(ctx, &empty.Empty{}).Return(test.versionRes, test.versionErr)
+
+		c.versionService = mock
+		_, err := c.Version(ctx, &runtime.VersionRequest{})
+		assert.Equal(t, test.expectErr, err != nil)
+	}
+}