feat: time interval extension method (aka pipe)

WotBlitzStatisticsPro.Blazor.Tests/Helpers/DatesHelperTests.cs

@@ -0,0 +1,32 @@
+using System;
+using FluentAssertions;
+using NUnit.Framework;
+using WotBlitzStatisticsPro.Blazor.Helpers;
+using WotBlitzStatisticsPro.Blazor.Model;
+
+namespace WotBlitzStatisticsPro.Blazor.Tests.Helpers
+{
+    public class DatesHelperTests
+    {
+        [SetUp]
+        public void Init()
+        {
+        }
+
+        [Test]
+        public void ShouldCalculateYears()
+        {
+            var currentDate = new DateTime(2021, 5, 18);
+
+            for (int i = 0; i < 10; i++)
+            {
+                var initialTime = currentDate.AddYears(-(1 + i * 3)).AddMonths(-i).AddDays(-i);
+                var result = DateDifferenceHelper.ParseTheDifference(currentDate - initialTime);
+                result.interval.Should().Be(TimeInterval.Year);
+                result.value.Should().Be(1 + i * 3);
+            }
+        }
+
+        // ToDo: Write months, days, hours and minutes scenarios
+    }
+}