Merge pull request #44443 from jamiehannaford/kubelet-tc

Automatic merge from submit-queue

Bump kubelet/networks test coverage

**What this PR does / why we need it**:

Bumps test coverage

**Which issue this PR fixes**:

https://github.com/kubernetes/kubernetes/issues/40780
https://github.com/kubernetes/kubernetes/issues/39559

**Special notes for your reviewer**:

Writing positive test cases for these lines:
https://github.com/kubernetes/kubernetes/blob/master/pkg/kubelet/networks.go#L38 https://github.com/kubernetes/kubernetes/blob/master/pkg/kubelet/networks.go#L69 
is quite difficult, so the former has a negative case and the latter has no test coverage.

**Release note**:
```release-note
New tests for kubelet/networks
```

pkg/kubelet/BUILD

@@ -153,6 +153,7 @@ go_test(
         "kubelet_resources_test.go",
         "kubelet_test.go",
         "kubelet_volumes_test.go",
+        "networks_test.go",
         "oom_watcher_test.go",
         "pod_container_deletor_test.go",
         "pod_workers_test.go",

pkg/kubelet/networks_test.go

@@ -0,0 +1,91 @@
+/*
+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 kubelet
+
+import (
+	"testing"
+)
+
+func TestNetworkHostGetsPodNotFound(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	actualPod, _ := nh.GetPodByName("", "")
+	if actualPod != nil {
+		t.Fatalf("Was expected nil, received %v instead", actualPod)
+	}
+}
+
+func TestNetworkHostGetsKubeClient(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	if nh.GetKubeClient() != testKubelet.fakeKubeClient {
+		t.Fatalf("NetworkHost client does not match testKubelet's client")
+	}
+}
+
+func TestNetworkHostGetsRuntime(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	if nh.GetRuntime() != testKubelet.fakeRuntime {
+		t.Fatalf("NetworkHost runtime does not match testKubelet's runtime")
+	}
+}
+
+func TestNetworkHostSupportsLegacyFeatures(t *testing.T) {
+	testKubelet := newTestKubelet(t, true)
+	defer testKubelet.Cleanup()
+	nh := networkHost{testKubelet.kubelet}
+
+	if nh.SupportsLegacyFeatures() == false {
+		t.Fatalf("SupportsLegacyFeatures should not be false")
+	}
+}
+
+func TestNoOpHostGetsName(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	pod, err := nh.GetPodByName("", "")
+	if pod != nil && err != true {
+		t.Fatalf("noOpLegacyHost getpodbyname expected to be nil and true")
+	}
+}
+
+func TestNoOpHostGetsKubeClient(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	if nh.GetKubeClient() != nil {
+		t.Fatalf("noOpLegacyHost client expected to be nil")
+	}
+}
+
+func TestNoOpHostGetsRuntime(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	if nh.GetRuntime() != nil {
+		t.Fatalf("noOpLegacyHost runtime expected to be nil")
+	}
+}
+
+func TestNoOpHostSupportsLegacyFeatures(t *testing.T) {
+	nh := NoOpLegacyHost{}
+	if nh.SupportsLegacyFeatures() != false {
+		t.Fatalf("noOpLegacyHost legacy features expected to be false")
+	}
+}