/** * Substract values */ public function testSubValues() { $currency = new Currency\Currency(array('currency' => 'EUR', 'locale' => 'de_AT')); $currency->sub(100); $this->assertEquals('-€ 100,00', $currency->toCurrency()); $currency->sub(100)->sub(100); $this->assertEquals('-€ 300,00', $currency->toCurrency()); }