Test writing configurations with numeric names

staging/src/k8s.io/client-go/tools/clientcmd/BUILD

@@ -18,6 +18,7 @@ go_test(
     embed = [":go_default_library"],
     deps = [
         "//staging/src/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//staging/src/k8s.io/apimachinery/pkg/util/diff:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/errors:go_default_library",
         "//staging/src/k8s.io/client-go/rest:go_default_library",
         "//staging/src/k8s.io/client-go/tools/clientcmd/api:go_default_library",

staging/src/k8s.io/client-go/tools/clientcmd/loader_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package clientcmd
 
 import (
+	"bytes"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -29,6 +30,7 @@ import (
 	"sigs.k8s.io/yaml"
 
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/util/diff"
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
 	clientcmdlatest "k8s.io/client-go/tools/clientcmd/api/latest"
 )
@@ -175,6 +177,56 @@ func TestConflictingCurrentContext(t *testing.T) {
 	}
 }
 
+func TestEncodeYAML(t *testing.T) {
+	config := clientcmdapi.Config{
+		CurrentContext: "any-context-value",
+		Contexts: map[string]*clientcmdapi.Context{
+			"433e40": {
+				Cluster: "433e40",
+			},
+		},
+		Clusters: map[string]*clientcmdapi.Cluster{
+			"0": {
+				Server: "https://localhost:1234",
+			},
+			"1": {
+				Server: "https://localhost:1234",
+			},
+			"433e40": {
+				Server: "https://localhost:1234",
+			},
+		},
+	}
+	data, err := Write(config)
+	if err != nil {
+		t.Fatal(err)
+	}
+	expected := []byte(`apiVersion: v1
+clusters:
+- cluster:
+    server: https://localhost:1234
+  name: "0"
+- cluster:
+    server: https://localhost:1234
+  name: "1"
+- cluster:
+    server: https://localhost:1234
+  name: "433e40"
+contexts:
+- context:
+    cluster: "433e40"
+    user: ""
+  name: "433e40"
+current-context: any-context-value
+kind: Config
+preferences: {}
+users: null
+`)
+	if !bytes.Equal(expected, data) {
+		t.Error(diff.ObjectReflectDiff(string(expected), string(data)))
+	}
+}
+
 func TestLoadingEmptyMaps(t *testing.T) {
 	configFile, _ := ioutil.TempFile("", "")
 	defer os.Remove(configFile.Name())