public function testAddFormatOverride()
 {
     $message = 'Hello "%world", how are you';
     $formatter1 = $this->createMock(FormatterInterface::class);
     $formatter1->method('has')->willReturn(true);
     $formatter1->method('formatValue')->willReturn('island');
     $formatter2 = $this->createMock(FormatterInterface::class);
     $formatter2->method('has')->willReturn(true);
     $formatter2->method('formatValue')->willReturn('city');
     $intlFormat = new IntlFormat([]);
     $intlFormat->addFormatter($formatter1);
     $intlFormat->addFormatter($formatter2);
     $this->assertSame('Hello "city", how are you', $intlFormat->format($message, 'city'));
 }