func TestFunc(t *testing.T) {
	// Create and write self-signed Certificate and Key to temporary files
	cert, key, err := testcerts.GenerateToTempFile("/tmp/")
	if err != nil {
		// do something
	}
	defer os.Remove(key)
	defer os.Remove(cert)

	// Start HTTP Listener with test certificates
	err = http.ListenAndServeTLS("127.0.0.1:443", cert, key, someHandler)
	if err != nil {
		// do something
	}
}

func TestFunc(t *testing.T) {
	// Generate Certificate Authority
	ca := testcerts.NewCA()

	go func() {
		// Create a signed Certificate and Key for "localhost"
		certs, err := ca.NewKeyPair("localhost")
		if err != nil {
			// do something
		}

		// Write certificates to a file
		err = certs.ToFile("/tmp/cert", "/tmp/key")
		if err {
			// do something
		}

		// Start HTTP Listener
		err = http.ListenAndServeTLS("localhost:443", "/tmp/cert", "/tmp/key", someHandler)
		if err != nil {
			// do something
		}
	}()

	// Create a client with the self-signed CA
	client := &http.Client{
		Transport: &http.Transport{
			TLSClientConfig: &tls.Config{
				RootCAs: ca.CertPool(),
			},
		},
	}

	// Make an HTTPS request
	r, _ := client.Get("https://localhost")
}