Move backzone stuff into datagen

Author: Manishearth

provider/src/tzdb/datagen.rs

@@ -86,9 +86,14 @@ pub enum IanaDataError {
 #[allow(clippy::expect_used, clippy::unwrap_used, reason = "Datagen only")]
 impl IanaIdentifierNormalizer<'_> {
     pub fn build(tzdata_path: &Path) -> Result<Self, IanaDataError> {
-        let provider = TzdbDataSource::try_from_zoneinfo_directory(tzdata_path)
+        let mut provider = TzdbDataSource::try_from_zoneinfo_directory(tzdata_path)
             .map_err(IanaDataError::Provider)?;
 
+        // This data includes things like Truk/Chuuk which Temporal requires in its tests
+        // It also includes the packrat data
+        let backzone = ZoneInfoData::from_filepath(tzdata_path.join("backzone")).unwrap();
+        provider.data.extend(backzone);
+
         let packrat_overrides: BTreeMap<_, _> = PACKRAT_OVERRIDES.iter().copied().collect();
 
         for pack in provider.data.pack_rat {

zoneinfo/src/lib.rs

@@ -67,7 +67,7 @@ use rule::Rules;
 use zone::ZoneRecord;
 
 /// Well-known zone info file
-pub const ZONEINFO_FILES: [&str; 10] = [
+pub const ZONEINFO_FILES: &[&str] = &[
     "africa",
     "antarctica",
     "asia",
@@ -77,7 +77,6 @@ pub const ZONEINFO_FILES: [&str; 10] = [
     "europe",
     "northamerica",
     "southamerica",
-    "backzone",
 ];
 
 /// The general error type for `ZoneInfo` operations