Merge pull request #39999 from tanshanshan/unit-test-scheduler1

Automatic merge from submit-queue (batch tested with PRs 40543, 39999)

Improve code coverage for scheduler/algorithm/priorities

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

Improve code coverage for scheduler/algorithm/priorities from #39559 

This is my first unit test  for kubernetes , thanks for your review.

**Special notes for your reviewer**:

**Release note**:

```release-note
```

plugin/pkg/scheduler/algorithm/priorities/BUILD

@@ -48,6 +48,7 @@ go_test(
         "image_locality_test.go",
         "interpod_affinity_test.go",
         "least_requested_test.go",
+        "metadata_test.go",
         "most_requested_test.go",
         "node_affinity_test.go",
         "node_label_test.go",

plugin/pkg/scheduler/algorithm/priorities/metadata_test.go

@@ -0,0 +1,142 @@
+/*
+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 priorities
+
+import (
+	"encoding/json"
+	"reflect"
+	"testing"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/kubernetes/pkg/api/resource"
+	"k8s.io/kubernetes/pkg/api/v1"
+	priorityutil "k8s.io/kubernetes/plugin/pkg/scheduler/algorithm/priorities/util"
+	"k8s.io/kubernetes/plugin/pkg/scheduler/schedulercache"
+)
+
+func TestPriorityMetadata(t *testing.T) {
+	nonZeroReqs := &schedulercache.Resource{}
+	nonZeroReqs.MilliCPU = priorityutil.DefaultMilliCpuRequest
+	nonZeroReqs.Memory = priorityutil.DefaultMemoryRequest
+
+	specifiedReqs := &schedulercache.Resource{}
+	specifiedReqs.MilliCPU = 200
+	specifiedReqs.Memory = 2000
+
+	tolerations := []v1.Toleration{{
+		Key:      "foo",
+		Operator: v1.TolerationOpEqual,
+		Value:    "bar",
+		Effect:   v1.TaintEffectPreferNoSchedule,
+	}}
+	tolerationData, _ := json.Marshal(tolerations)
+	podAffinity := &v1.Affinity{
+		PodAffinity: &v1.PodAffinity{
+			PreferredDuringSchedulingIgnoredDuringExecution: []v1.WeightedPodAffinityTerm{
+				{
+					Weight: 5,
+					PodAffinityTerm: v1.PodAffinityTerm{
+						LabelSelector: &metav1.LabelSelector{
+							MatchExpressions: []metav1.LabelSelectorRequirement{
+								{
+									Key:      "security",
+									Operator: metav1.LabelSelectorOpIn,
+									Values:   []string{"S1"},
+								},
+							},
+						},
+						TopologyKey: "region",
+					},
+				},
+			},
+		},
+	}
+	podWithTolerationsAndAffinity := &v1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Annotations: map[string]string{
+				v1.TolerationsAnnotationKey: string(tolerationData),
+			},
+		},
+		Spec: v1.PodSpec{
+			Containers: []v1.Container{
+				{
+					Name:            "container",
+					Image:           "image",
+					ImagePullPolicy: "Always",
+				},
+			},
+			Affinity: podAffinity,
+		},
+	}
+	podWithTolerationsAndRequests := &v1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Annotations: map[string]string{
+				v1.TolerationsAnnotationKey: string(tolerationData),
+			},
+		},
+		Spec: v1.PodSpec{
+			Containers: []v1.Container{
+				{
+					Name:            "container",
+					Image:           "image",
+					ImagePullPolicy: "Always",
+					Resources: v1.ResourceRequirements{
+						Requests: v1.ResourceList{
+							"cpu":    resource.MustParse("200m"),
+							"memory": resource.MustParse("2000"),
+						},
+					},
+				},
+			},
+		},
+	}
+	tests := []struct {
+		pod      *v1.Pod
+		test     string
+		expected interface{}
+	}{
+		{
+			pod:      nil,
+			expected: nil,
+			test:     "pod is nil , priorityMetadata is nil",
+		},
+		{
+			pod: podWithTolerationsAndAffinity,
+			expected: &priorityMetadata{
+				nonZeroRequest: nonZeroReqs,
+				podTolerations: tolerations,
+				affinity:       podAffinity,
+			},
+			test: "Produce a priorityMetadata with default requests",
+		},
+		{
+			pod: podWithTolerationsAndRequests,
+			expected: &priorityMetadata{
+				nonZeroRequest: specifiedReqs,
+				podTolerations: tolerations,
+				affinity:       nil,
+			},
+			test: "Produce a priorityMetadata with specified requests",
+		},
+	}
+	for _, test := range tests {
+		ptData := PriorityMetadata(test.pod, nil)
+		if !reflect.DeepEqual(test.expected, ptData) {
+			t.Errorf("%s: expected %#v, got %#v", test.test, test.expected, ptData)
+		}
+	}
+}