Sort arguments before joining them, for reproducible return string

cmd/kubeadm/app/util/arguments.go

@@ -18,17 +18,32 @@ package util
 
 import (
 	"fmt"
+	"sort"
 	"strings"
 )
 
-// BuildArgumentListFromMap takes two string-string maps, one with the base arguments and one with optional override arguments
+// BuildArgumentListFromMap takes two string-string maps, one with the base arguments and one
+// with optional override arguments. In the return list override arguments will precede base
+// arguments
 func BuildArgumentListFromMap(baseArguments map[string]string, overrideArguments map[string]string) []string {
 	var command []string
-	for k, v := range overrideArguments {
+	var keys []string
+	for k := range overrideArguments {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		v := overrideArguments[k]
 		// values of "" are allowed as well
 		command = append(command, fmt.Sprintf("--%s=%s", k, v))
 	}
-	for k, v := range baseArguments {
+	keys = []string{}
+	for k := range baseArguments {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		v := baseArguments[k]
 		if _, overrideExists := overrideArguments[k]; !overrideExists {
 			command = append(command, fmt.Sprintf("--%s=%s", k, v))
 		}

cmd/kubeadm/app/util/arguments_test.go

@@ -39,8 +39,8 @@ func TestBuildArgumentListFromMap(t *testing.T) {
 			},
 			expected: []string{
 				"--admission-control=NamespaceLifecycle,LimitRanger",
-				"--insecure-bind-address=127.0.0.1",
 				"--allow-privileged=true",
+				"--insecure-bind-address=127.0.0.1",
 			},
 		},
 		{ // add an argument that is not in base
@@ -53,8 +53,8 @@ func TestBuildArgumentListFromMap(t *testing.T) {
 			},
 			expected: []string{
 				"--admission-control=NamespaceLifecycle,LimitRanger",
-				"--insecure-bind-address=127.0.0.1",
 				"--allow-privileged=true",
+				"--insecure-bind-address=127.0.0.1",
 			},
 		},
 		{ // allow empty strings in base
@@ -68,8 +68,8 @@ func TestBuildArgumentListFromMap(t *testing.T) {
 			},
 			expected: []string{
 				"--admission-control=NamespaceLifecycle,LimitRanger",
-				"--insecure-bind-address=127.0.0.1",
 				"--allow-privileged=true",
+				"--insecure-bind-address=127.0.0.1",
 				"--something-that-allows-empty-string=",
 			},
 		},
@@ -85,17 +85,15 @@ func TestBuildArgumentListFromMap(t *testing.T) {
 			},
 			expected: []string{
 				"--admission-control=NamespaceLifecycle,LimitRanger",
-				"--insecure-bind-address=127.0.0.1",
-				"--allow-privileged=true",
 				"--something-that-allows-empty-string=",
+				"--allow-privileged=true",
+				"--insecure-bind-address=127.0.0.1",
 			},
 		},
 	}
 
 	for _, rt := range tests {
 		actual := BuildArgumentListFromMap(rt.base, rt.overrides)
-		sort.Strings(actual)
-		sort.Strings(rt.expected)
 		if !reflect.DeepEqual(actual, rt.expected) {
 			t.Errorf("failed BuildArgumentListFromMap:\nexpected:\n%v\nsaw:\n%v", rt.expected, actual)
 		}