add cmd-test for sort-by command

hack/lib/test.sh

@@ -250,6 +250,17 @@ kube::test::describe_resource_events_assert() {
     fi
 }
 
+# Compare sort-by resource name output with expected order specify in the last parameter
+kube::test::if_sort_by_has_correct_order() {
+  local array=($(echo "$1" |awk '{if(NR!=1) print $1}'))
+  local var
+  for i in "${array[@]}"; do
+    var+="$i:"
+  done
+
+  kube::test::if_has_string "$var" "${@:$#}"
+}
+
 kube::test::if_has_string() {
   local message=$1
   local match=$2

hack/make-rules/test-cmd-util.sh

@@ -3940,6 +3940,38 @@ run_kubectl_sort_by_tests() {
   # Post-condition: valid-pod doesn't exist
   kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" ''
 
+  ### sort-by should works by sorting by name
+  # Create three PODs
+  # Pre-condition: no POD exists
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" ''
+  # Command
+  kubectl create "${kube_flags[@]}" -f hack/testdata/sorted-pods/sorted-pod1.yaml
+  # Post-condition: sorted-pod1 is created
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" 'sorted-pod1:'
+  # Command
+  kubectl create "${kube_flags[@]}" -f hack/testdata/sorted-pods/sorted-pod2.yaml
+  # Post-condition: sorted-pod1 is created
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" 'sorted-pod1:sorted-pod2:'
+  # Command
+  kubectl create "${kube_flags[@]}" -f hack/testdata/sorted-pods/sorted-pod3.yaml
+  # Post-condition: sorted-pod1 is created
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" 'sorted-pod1:sorted-pod2:sorted-pod3:'
+
+  # Check output of sort-by '{metadata.name}'
+  output_message=$(kubectl get pods --sort-by="{metadata.name}")
+  kube::test::if_sort_by_has_correct_order "${output_message}" "sorted-pod1:sorted-pod2:sorted-pod3:"
+
+  # Check output of sort-by '{metadata.labels.name}'
+  output_message=$(kubectl get pods --sort-by="{metadata.labels.name}")
+  kube::test::if_sort_by_has_correct_order "${output_message}" "sorted-pod3:sorted-pod2:sorted-pod1:"
+
+  ### Clean up
+  # Pre-condition: valid-pod exists
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" 'sorted-pod1:sorted-pod2:sorted-pod3:'
+  # Command
+  kubectl delete "${kube_flags[@]}" pod --grace-period=0 --force --all
+  # Post-condition: valid-pod doesn't exist
+  kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" ''
 
   set +o nounset
   set +o errexit

hack/testdata/sorted-pods/sorted-pod1.yaml

+apiVersion: v1
+kind: Pod
+metadata:
+  name: sorted-pod1
+  labels:
+    name: sorted-pod3-label
+spec:
+  containers:
+  - name: kubernetes-pause
+    image: gcr.io/google-containers/pause:2.0

hack/testdata/sorted-pods/sorted-pod2.yaml

+apiVersion: v1
+kind: Pod
+metadata:
+  name: sorted-pod2
+  labels:
+    name: sorted-pod2-label
+spec:
+  containers:
+  - name: kubernetes-pause
+    image: gcr.io/google-containers/pause:2.0

hack/testdata/sorted-pods/sorted-pod3.yaml

+apiVersion: v1
+kind: Pod
+metadata:
+  name: sorted-pod3
+  labels:
+    name: sorted-pod1-label
+spec:
+  containers:
+  - name: kubernetes-pause
+    image: gcr.io/google-containers/pause:2.0