Datetime differences tests added

Author: BrawlerXull

test/taskfunctions/datetime_differences_test.dart

@@ -0,0 +1,96 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:taskwarrior/app/utils/taskfunctions/datetime_differences.dart';
+
+void main() {
+  group('DateTime Functions Tests', () {
+    test('Test age function', () {
+      DateTime dt = DateTime.now().subtract(const Duration(days: 365));
+      String result = age(dt);
+      expect(result, contains('12mo '));
+
+      dt = DateTime.now().subtract(const Duration(days: 60));
+      result = age(dt);
+      expect(result, contains('2mo '));
+
+      dt = DateTime.now().subtract(const Duration(days: 21));
+      result = age(dt);
+      expect(result, contains('3w '));
+
+      dt = DateTime.now().subtract(const Duration(days: 4));
+      result = age(dt);
+      expect(result, contains('4d '));
+
+      dt = DateTime.now().subtract(const Duration(hours: 5));
+      result = age(dt);
+      expect(result, contains('5h '));
+
+      dt = DateTime.now().subtract(const Duration(minutes: 10));
+      result = age(dt);
+      expect(result, contains('10min '));
+
+      dt = DateTime.now().subtract(const Duration(seconds: 30));
+      result = age(dt);
+      expect(result, contains('30s '));
+    });
+
+    test('Test when function', () {
+      DateTime dt = DateTime.now().add(const Duration(days: 365));
+      String result = when(dt);
+      expect(result, contains('12mo'));
+
+      dt = DateTime.now().add(const Duration(days: 60));
+      result = when(dt);
+      expect(result, contains('1mo'));
+
+      dt = DateTime.now().add(const Duration(days: 21));
+      result = when(dt);
+      expect(result, contains('2w'));
+
+      dt = DateTime.now().add(const Duration(days: 4));
+      result = when(dt);
+      expect(result, contains('3d'));
+
+      dt = DateTime.now().add(const Duration(hours: 5));
+      result = when(dt);
+      expect(result, contains('4h'));
+
+      dt = DateTime.now().add(const Duration(minutes: 10));
+      result = when(dt);
+      expect(result, contains('9min'));
+
+      dt = DateTime.now().add(const Duration(seconds: 30));
+      result = when(dt);
+      expect(result, contains('29s'));
+    });
+
+    test('Test difference function', () {
+      DateTime dt = DateTime.now().subtract(const Duration(days: 365));
+      String result = difference(DateTime.now().difference(dt));
+      expect(result, contains('12mo '));
+
+      dt = DateTime.now().subtract(const Duration(days: 60));
+      result = difference(DateTime.now().difference(dt));
+      expect(result, contains('2mo '));
+
+      dt = DateTime.now().subtract(const Duration(days: 21));
+      result = difference(DateTime.now().difference(dt));
+      expect(result, contains('3w '));
+
+      dt = DateTime.now().subtract(const Duration(days: 4));
+      result = difference(DateTime.now().difference(dt));
+      expect(result, contains('4d '));
+
+      dt = DateTime.now().subtract(const Duration(hours: 5));
+      result = difference(DateTime.now().difference(dt));
+      expect(result, contains('5h '));
+
+      dt = DateTime.now().subtract(const Duration(minutes: 10));
+      result = difference(DateTime.now().difference(dt));
+      expect(result, contains('10min '));
+
+      dt = DateTime.now().subtract(const Duration(seconds: 30));
+      result = difference(DateTime.now().difference(dt));
+      expect(result, contains('30s '));
+    });
+  });
+}