vsphere/tags_helper.go
func (p *tagDiffProcessor) diff(a, b []string) []string {
	var found bool
	c := make([]string, 0)
	for _, v1 := range a {
		for _, v2 := range b {
			if v1 == v2 {
				found = true
			}
		}
		if !found {
			c = append(c, v1)
		}
		found = false
	}
	return c
}
func (p *tagDiffProcessor) diff(a, b []string) []string {
	var found bool
	c := make([]string, 0)
	for _, v1 := range a {
		for _, v2 := range b {
			if v1 == v2 {
				found = true
			}
		}
		if !found {
			c = append(c, v1)
		}
		found = false
	}
	return c
}
// diff is what diffOldNew and diffNewOld hand off to.