func GetLengthOfNationalDestinationCode()

in phonenumbers.go [962:999]

• 22 lines of code
• 5 McCabe index (conditional complexity)

func GetLengthOfNationalDestinationCode(number *PhoneNumber) int {
	var copiedProto *PhoneNumber
	if len(number.GetExtension()) > 0 {
		// We don't want to alter the proto given to us, but we don't
		// want to include the extension when we format it, so we copy
		// it and clear the extension here.
		copiedProto = &PhoneNumber{}
		proto.Merge(copiedProto, number)
		copiedProto.Extension = nil
	} else {
		copiedProto = number
	}

	nationalSignificantNumber := Format(copiedProto, INTERNATIONAL)
	numberGroups := NON_DIGITS_PATTERN.Split(nationalSignificantNumber, -1)

	// The pattern will start with "+COUNTRY_CODE " so the first group
	// will always be the empty string (before the + symbol) and the
	// second group will be the country calling code. The third group
	// will be area code if it is not the last group.
	if len(numberGroups) <= 3 {
		return 0
	}
	if GetNumberType(number) == MOBILE {
		// For example Argentinian mobile numbers, when formatted in
		// the international format, are in the form of +54 9 NDC XXXX....
		// As a result, we take the length of the third group (NDC) and
		// add the length of the second group (which is the mobile token),
		// which also forms part of the national significant number. This
		// assumes that the mobile token is always formatted separately
		// from the rest of the phone number.
		mobileToken := GetCountryMobileToken(int(number.GetCountryCode()))
		if mobileToken != "" {
			return len(numberGroups[1]) + len(numberGroups[2])
		}
	}
	return len(numberGroups[2])
}