libphonenumber\PhoneNumberUtil::getMetadataForRegion PHP Method

    public function getMetadataForRegion($regionCode)
    {
        if (!$this->isValidRegionCode($regionCode)) {
            return null;
        }
        return $this->metadataSource->getMetadataForRegion($regionCode);
    }

 public function testGetInstanceLoadARMetadata()
 {
     $metadata = $this->phoneUtil->getMetadataForRegion(RegionCode::AR);
     $this->assertEquals("AR", $metadata->getId());
     $this->assertEquals(54, $metadata->getCountryCode());
     $this->assertEquals("00", $metadata->getInternationalPrefix());
     $this->assertEquals("0", $metadata->getNationalPrefix());
     $this->assertEquals("0(?:(11|343|3715)15)?", $metadata->getNationalPrefixForParsing());
     $this->assertEquals("9\$1", $metadata->getNationalPrefixTransformRule());
     $this->assertEquals("\$2 15 \$3-\$4", $metadata->getNumberFormat(2)->getFormat());
     $this->assertEquals("(9)(\\d{4})(\\d{2})(\\d{4})", $metadata->getNumberFormat(3)->getPattern());
     $this->assertEquals("(9)(\\d{4})(\\d{2})(\\d{4})", $metadata->getIntlNumberFormat(3)->getPattern());
     $this->assertEquals("\$1 \$2 \$3 \$4", $metadata->getIntlNumberFormat(3)->getFormat());
 }