Clean up the copy method + unit test

nomad/structs/structs.go

@@ -4922,6 +4922,20 @@ type RescheduleTracker struct {
 	Events []*RescheduleEvent
 }
 
+func (rt *RescheduleTracker) Copy() *RescheduleTracker {
+	if rt == nil {
+		return nil
+	}
+	nt := &RescheduleTracker{}
+	*nt = *rt
+	rescheduleEvents := make([]*RescheduleEvent, 0, len(rt.Events))
+	for _, tracker := range rt.Events {
+		rescheduleEvents = append(rescheduleEvents, tracker.Copy())
+	}
+	nt.Events = rescheduleEvents
+	return nt
+}
+
 // RescheduleEvent is used to keep track of previous attempts at rescheduling an allocation
 type RescheduleEvent struct {
 	// RescheduleTime is the timestamp of a reschedule attempt
@@ -4934,12 +4948,12 @@ type RescheduleEvent struct {
 	PrevNodeID string
 }
 
-func (rt *RescheduleEvent) Copy() *RescheduleEvent {
-	if rt == nil {
+func (re *RescheduleEvent) Copy() *RescheduleEvent {
+	if re == nil {
 		return nil
 	}
 	copy := new(RescheduleEvent)
-	*copy = *rt
+	*copy = *re
 	return copy
 }
 
@@ -5102,12 +5116,7 @@ func (a *Allocation) copyImpl(job bool) *Allocation {
 		na.TaskStates = ts
 	}
 
-	if a.RescheduleTracker != nil {
-		var rescheduleTrackers []*RescheduleEvent
-		for _, tracker := range a.RescheduleTracker.Events {
-			rescheduleTrackers = append(rescheduleTrackers, tracker.Copy())
-		}
-	}
+	na.RescheduleTracker = a.RescheduleTracker.Copy()
 	return na
 }
 

nomad/structs/structs_test.go

@@ -2800,6 +2800,28 @@ func TestAllocation_ShouldReschedule(t *testing.T) {
 	}
 }
 
+func TestRescheduleTracker_Copy(t *testing.T) {
+	type testCase struct {
+		original *RescheduleTracker
+		expected *RescheduleTracker
+	}
+
+	cases := []testCase{
+		{nil, nil},
+		{&RescheduleTracker{Events: []*RescheduleEvent{
+			{2, "12", "12"},
+		}}, &RescheduleTracker{Events: []*RescheduleEvent{
+			{2, "12", "12"},
+		}}},
+	}
+
+	for _, tc := range cases {
+		if got := tc.original.Copy(); !reflect.DeepEqual(got, tc.expected) {
+			t.Fatalf("expected %v but got %v", *tc.expected, *got)
+		}
+	}
+}
+
 func TestVault_Validate(t *testing.T) {
 	v := &Vault{
 		Env:        true,