public function testGetSupportedGlobalNetworkCallingCodes()
{
$globalNetworkCallingCodes = $this->phoneUtil->getSupportedGlobalNetworkCallingCodes();
$this->assertGreaterThan(0, count($globalNetworkCallingCodes));
foreach ($globalNetworkCallingCodes as $callingCode) {
$this->assertGreaterThan(0, $callingCode);
$this->assertEquals(RegionCode::UN001, $this->phoneUtil->getRegionCodeForCountryCode($callingCode));
}
}