Alternative to #4: Remove tuple

lib/src/date_time.dart

@@ -88,14 +88,14 @@ class TZDateTime implements DateTime {
     } else {
       var unix = _localDateTime.millisecondsSinceEpoch;
       var tzData = _location.lookupTimeZone(unix);
-      if (tzData.i1.offset != 0) {
-        final utc = unix - tzData.i1.offset;
-        if (utc < tzData.i2) {
-          tzData = _location.lookupTimeZone(tzData.i2 - 1);
-        } else if (utc >= tzData.i3) {
-          tzData = _location.lookupTimeZone(tzData.i3);
+      if (tzData.timeZone.offset != 0) {
+        final utc = unix - tzData.timeZone.offset;
+        if (utc < tzData.start) {
+          tzData = _location.lookupTimeZone(tzData.start - 1);
+        } else if (utc >= tzData.end) {
+          tzData = _location.lookupTimeZone(tzData.end);
         }
-        unix -= tzData.i1.offset;
+        unix -= tzData.timeZone.offset;
       }
       _millisecondsSinceEpoch = unix;
 

lib/src/location.dart

@@ -10,8 +10,6 @@
 /// and ported to Dart.
 library timezone.src.location;
 
-import 'package:tuple/tuple.dart';
-
 /// Zone Info header size.
 const int _zoneInfoHeaderSize = 16;
 
@@ -83,19 +81,19 @@ class Location {
   /// January 1, 1970 00:00:00 to UTC.
   int translateToUtc(int millisecondsSinceEpoch) {
     final t = lookupTimeZone(millisecondsSinceEpoch);
-    final tz = t.i1;
-    final start = t.i2;
-    final end = t.i3;
+    final tz = t.timeZone;
+    final start = t.start;
+    final end = t.end;
 
     var utc = millisecondsSinceEpoch;
 
     if (tz.offset != 0) {
       utc -= tz.offset;
 
       if (utc < start) {
-        utc = millisecondsSinceEpoch - lookupTimeZone(start - 1).i1.offset;
+        utc = millisecondsSinceEpoch - lookupTimeZone(start - 1).timeZone.offset;
       } else if (utc >= end) {
-        utc = millisecondsSinceEpoch - lookupTimeZone(end).i1.offset;
+        utc = millisecondsSinceEpoch - lookupTimeZone(end).timeZone.offset;
       }
     }
 
@@ -104,22 +102,22 @@ class Location {
 
   /// lookup for [TimeZone] and its boundaries for an instant in time expressed
   /// as milliseconds since January 1, 1970 00:00:00 UTC.
-  PersistentTuple3<TimeZone, int, int> lookupTimeZone(int millisecondsSinceEpoch) {
+  TzInstant lookupTimeZone(int millisecondsSinceEpoch) {
     if (zones.isEmpty) {
-      return const PersistentTuple3(const TimeZone(0, false, 'UTC'), minTime, maxTime);
+      return const TzInstant(const TimeZone(0, false, 'UTC'), minTime, maxTime);
     }
 
     if (_cacheZone != null &&
         millisecondsSinceEpoch >= _cacheStart &&
         millisecondsSinceEpoch < _cacheEnd) {
-      return new PersistentTuple3(_cacheZone, _cacheStart, _cacheEnd);
+      return new TzInstant(_cacheZone, _cacheStart, _cacheEnd);
     }
 
     if (transitionAt.isEmpty || millisecondsSinceEpoch < transitionAt[0]) {
       final zone = _firstZone();
       final start = minTime;
       final end = transitionAt.isEmpty ? maxTime : transitionAt.first;
-      return new PersistentTuple3(zone, start, end);
+      return new TzInstant(zone, start, end);
     }
 
     // Binary search for entry with largest millisecondsSinceEpoch <= sec.
@@ -139,30 +137,30 @@ class Location {
       }
     }
 
-    return new PersistentTuple3(zones[transitionZone[lo]], transitionAt[lo], end);
+    return new TzInstant(zones[transitionZone[lo]], transitionAt[lo], end);
   }
 
   /// timeZone method returns [TimeZone] in use at an instant in time expressed
   /// as milliseconds since January 1, 1970 00:00:00 UTC.
   TimeZone timeZone(int millisecondsSinceEpoch) {
-    return lookupTimeZone(millisecondsSinceEpoch).i1;
+    return lookupTimeZone(millisecondsSinceEpoch).timeZone;
   }
 
   /// timeZoneFromLocal method returns [TimeZone] in use at an instant in time
   /// expressed as milliseconds since January 1, 1970 00:00:00.
   TimeZone timeZoneFromLocal(int millisecondsSinceEpoch) {
     final t = lookupTimeZone(millisecondsSinceEpoch);
-    var tz = t.i1;
-    final start = t.i2;
-    final end = t.i3;
+    var tz = t.timeZone;
+    final start = t.start;
+    final end = t.end;
 
     if (tz.offset != 0) {
       final utc = millisecondsSinceEpoch - tz.offset;
 
       if (utc < start) {
-        tz = lookupTimeZone(start - 1).i1;
+        tz = lookupTimeZone(start - 1).timeZone;
       } else if (utc >= end) {
-        tz = lookupTimeZone(end).i1;
+        tz = lookupTimeZone(end).timeZone;
       }
     }
 
@@ -255,4 +253,13 @@ class TimeZone {
   }
 
   String toString() => '[$abbr offset=$offset dst=$isDst]';
-}
+}
+
+/// A [TzInstant] represents a timezone and an instant in time.
+class TzInstant {
+  final TimeZone timeZone;
+  final int start;
+  final int end;
+
+  const TzInstant(this.timeZone, this.start, this.end);
+}

lib/src/tools.dart

@@ -5,7 +5,6 @@
 library timezone.src.tools;
 
 import 'dart:collection';
-import 'package:tuple/tuple.dart';
 import 'package:timezone/tzdata.dart' as tzfile;
 import 'package:timezone/timezone.dart';
 
@@ -1035,7 +1034,14 @@ class FilterReport {
   int newTransitionsCount = 0;
 }
 
-Tuple2<LocationDatabase, FilterReport> filterTimeZoneData(
+class FilteredLocationDatabase {
+  final LocationDatabase db;
+  final FilterReport report;
+
+  FilteredLocationDatabase(this.db, this.report);
+}
+
+FilteredLocationDatabase filterTimeZoneData(
     LocationDatabase db,
     {int dateFrom: TZDateTime.minMillisecondsSinceEpoch,
      int dateTo: TZDateTime.maxMillisecondsSinceEpoch,
@@ -1093,7 +1099,7 @@ Tuple2<LocationDatabase, FilterReport> filterTimeZoneData(
     report.newLocationsCount++;
   }
 
-  return new Tuple2(result, report);
+  return new FilteredLocationDatabase(result, report);
 }
 
 /// Convert [tzfile.Location] to [Location]

pubspec.yaml

@@ -6,8 +6,7 @@ homepage: https://github.com/localvoid/timezone
 environment:
   sdk: '>=1.9.0'
 dependencies:
-  tuple: '>=0.1.0 <0.2.0'
-  path: '>=1.3.0 <1.4.0'
+  path: '^1.3.0'
 dev_dependencies:
   args: any
   browser: any

tool/get.dart

@@ -145,26 +145,26 @@ Future main(List<String> arguments) async {
 
   log.info('- all locations');
   final allDb = filterTimeZoneData(db, locations: allLocations);
-  logReport(allDb.i2);
+  logReport(allDb.report);
 
   log.info('- common locations from all locations');
-  final commonDb = filterTimeZoneData(allDb.i1, locations: commonLocations);
-  logReport(commonDb.i2);
+  final commonDb = filterTimeZoneData(allDb.db, locations: commonLocations);
+  logReport(commonDb.report);
 
   log.info('- [2010 - 2020 years] from common locations');
-  final common_2010_2020_Db = filterTimeZoneData(commonDb.i1,
+  final common_2010_2020_Db = filterTimeZoneData(commonDb.db,
   dateFrom: new DateTime.utc(2010, 1, 1).millisecondsSinceEpoch,
   dateTo: new DateTime.utc(2020, 1, 1).millisecondsSinceEpoch,
   locations: commonLocations);
-  logReport(common_2010_2020_Db.i2);
+  logReport(common_2010_2020_Db.report);
 
   log.info('Serializing location databases');
   final allOut = new File(ospath.join(outPath, '${source}_all.$tzDataExtension'));
   final commonOut = new File(ospath.join(outPath, '${source}.$tzDataExtension'));
   final common_2010_2020_Out = new File(ospath.join(outPath, '${source}_2010-2020.$tzDataExtension'));
-  await allOut.writeAsBytes(tzdbSerialize(allDb.i1), flush: true);
-  await commonOut.writeAsBytes(tzdbSerialize(commonDb.i1), flush: true);
-  await common_2010_2020_Out.writeAsBytes(tzdbSerialize(common_2010_2020_Db.i1), flush: true);
+  await allOut.writeAsBytes(tzdbSerialize(allDb.db), flush: true);
+  await commonOut.writeAsBytes(tzdbSerialize(commonDb.db), flush: true);
+  await common_2010_2020_Out.writeAsBytes(tzdbSerialize(common_2010_2020_Db.db), flush: true);
 
   exit(0);
 }