Update GetLengthOfGeographicalAreaCode to match recent libphonenumber…

… changes

phonenumbers.go

@@ -413,6 +413,19 @@ var (
  RFC3966_TOPLABEL = "[" + VALID_ALPHA + "]+((\\-)*[" + ALPHANUM + "])*"
  RFC3966_DOMAINNAME = "^(" + RFC3966_DOMAINLABEL + "\\.)*" + RFC3966_TOPLABEL + "\\.?$"
  RFC3966_DOMAINNAME_PATTERN = regexp.MustCompile(RFC3966_DOMAINNAME)
+
+ // Set of country codes that have geographically assigned mobile numbers (see GEO_MOBILE_COUNTRIES
+ // below) which are not based on *area codes*. For example, in China mobile numbers start with a
+ // carrier indicator, and beyond that are geographically assigned: this carrier indicator is not
+ // considered to be an area code.
+ GEO_MOBILE_COUNTRIES_WITHOUT_MOBILE_AREA_CODES = map[int32]bool{
+ 86: true, // China
+ }
+
+ // Set of country codes that doesn't have national prefix, but it has area codes.
+ COUNTRIES_WITHOUT_NATIONAL_PREFIX_WITH_AREA_CODES = map[int32]bool{
+ 52: true, // Mexico
+ }
 )
 
 // INTERNATIONAL and NATIONAL formats are consistent with the definition
@@ -893,10 +906,21 @@ func GetLengthOfGeographicalAreaCode(number *PhoneNumber) int {
  return 0
  }
 
- // If a country doesn't use a national prefix, and this number
- // doesn't have an Italian leading zero, we assume it is a closed
- // dialling plan with no area codes.
- if len(metadata.GetNationalPrefix()) == 0 && !number.GetItalianLeadingZero() {
+ numType := GetNumberType(number)
+ countryCallingCode := number.GetCountryCode()
+
+ // If a country doesn't use a national prefix, and this number doesn't have an Italian leading
+ // zero, we assume it is a closed dialling plan with no area codes.
+ // Note:this is our general assumption, but there are exceptions which are tracked in
+ // COUNTRIES_WITHOUT_NATIONAL_PREFIX_WITH_AREA_CODES.
+ if len(metadata.GetNationalPrefix()) == 0 && !number.GetItalianLeadingZero() && !COUNTRIES_WITHOUT_NATIONAL_PREFIX_WITH_AREA_CODES[countryCallingCode] {
+ return 0
+ }
+
+ // Note this is a rough heuristic; it doesn't cover Indonesia well, for example, where area
+ // codes are present for some mobile phones but not for others. We have no better way of
+ // representing this in the metadata at this point.
+ if numType == MOBILE && GEO_MOBILE_COUNTRIES_WITHOUT_MOBILE_AREA_CODES[countryCallingCode] {
  return 0
  }