libphonenumber\PhoneNumberUtil::getSupportedRegions PHP Method

    public function getSupportedRegions()
    {
        return $this->supportedRegions;
    }

 /**
  * @dataProvider localeList
  * @param string $regionCode
  * @param string $countryName
  */
 public function testLocales($regionCode, $countryName)
 {
     if (!in_array($regionCode, $this->phoneUtil->getSupportedRegions())) {
         $this->markTestSkipped("{$regionCode} is not supported");
     }
     $phoneNumber = $this->phoneUtil->getExampleNumberForType($regionCode, PhoneNumberType::FIXED_LINE_OR_MOBILE);
     $this->assertContains($regionCode, CountryCodeToRegionCodeMap::$countryCodeToRegionCodeMap[$phoneNumber->getCountryCode()]);
     $this->assertEquals($regionCode, $this->phoneUtil->getRegionCodeForNumber($phoneNumber));
     $this->assertEquals($countryName, $this->geocoder->getDescriptionForValidNumber($phoneNumber, 'en', 'ZZ'), "Checking {$phoneNumber} is part of {$countryName}");
 }