kubelet: Remove unnecessary sorting in NodeAddress tests

Several of the tests in TestNodeAddress() were no-ops because the test
code was only testing that NodeAddresses() returned all of the
expected addresses, but not testing that it was returning them in the
correct order.

The order that NodeAddresses() returns addresses in is very important,
so fix the tests to actually test it.

One existing test ("NodeIP is external") had its expectedAddresses in
the wrong order, but it seems clear from the name of the test that
this isn't actually what it expected.

Also, previously testKubeletHostname was "127.0.0.1" which ended up
interacting weirdly with the IPv4-vs-IPv6 sorting code in a way that
made some of the test results confusing if you didn't realize that
testKubeletHostname was an IPv4 address. Fix that by making it an
actual hostname instead, which then preserves the expected sorting.

Author: danwinship

pkg/kubelet/nodestatus/setters_test.go

@@ -50,7 +50,7 @@ import (
 )
 
 const (
-	testKubeletHostname = "127.0.0.1"
+	testKubeletHostname = "hostname"
 )
 
 // TODO(mtaufen): below is ported from the old kubelet_node_status_test.go code, potentially add more test coverage for NodeAddress setter in future
@@ -86,8 +86,8 @@ func TestNodeAddress(t *testing.T) {
 				{Type: v1.NodeHostName, Address: testKubeletHostname},
 			},
 			expectedAddresses: []v1.NodeAddress{
-				{Type: v1.NodeInternalIP, Address: "10.1.1.1"},
 				{Type: v1.NodeExternalIP, Address: "55.55.55.55"},
+				{Type: v1.NodeInternalIP, Address: "10.1.1.1"},
 				{Type: v1.NodeHostName, Address: testKubeletHostname},
 			},
 			shouldError: false,
@@ -433,10 +433,6 @@ func TestNodeAddress(t *testing.T) {
 				return
 			}
 
-			// Sort both sets for consistent equality
-			sortNodeAddresses(testCase.expectedAddresses)
-			sortNodeAddresses(existingNode.Status.Addresses)
-
 			assert.True(t, apiequality.Semantic.DeepEqual(testCase.expectedAddresses, existingNode.Status.Addresses),
 				"Diff: %s", diff.ObjectDiff(testCase.expectedAddresses, existingNode.Status.Addresses))
 		})
@@ -1678,19 +1674,6 @@ func TestVolumeLimits(t *testing.T) {
 
 // Test Helpers:
 
-// sortableNodeAddress is a type for sorting []v1.NodeAddress
-type sortableNodeAddress []v1.NodeAddress
-
-func (s sortableNodeAddress) Len() int { return len(s) }
-func (s sortableNodeAddress) Less(i, j int) bool {
-	return (string(s[i].Type) + s[i].Address) < (string(s[j].Type) + s[j].Address)
-}
-func (s sortableNodeAddress) Swap(i, j int) { s[j], s[i] = s[i], s[j] }
-
-func sortNodeAddresses(addrs sortableNodeAddress) {
-	sort.Sort(addrs)
-}
-
 // testEvent is used to record events for tests
 type testEvent struct {
 	eventType string