Teilnahmerechnungen erstellen

tests/Unit/DateRangeTest.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace Tests\Unit;
+
+use App\Support\DateRange;
+use DateTime;
+use PHPUnit\Framework\TestCase;
+
+class DateRangeTest extends TestCase
+{
+    public function test_a_single_day_counts_as_one(): void
+    {
+        $day = new DateTime('2026-07-16');
+
+        $this->assertSame(1, DateRange::inclusiveDays($day, $day));
+    }
+
+    public function test_both_ends_are_counted(): void
+    {
+        // An- und Abreisetag zählen beide mit.
+        $this->assertSame(2, DateRange::inclusiveDays(new DateTime('2026-07-16'), new DateTime('2026-07-17')));
+        $this->assertSame(5, DateRange::inclusiveDays(new DateTime('2026-07-16'), new DateTime('2026-07-20')));
+    }
+
+    public function test_the_order_of_the_arguments_does_not_matter(): void
+    {
+        $early = new DateTime('2026-07-16');
+        $late = new DateTime('2026-07-20');
+
+        $this->assertSame(
+            DateRange::inclusiveDays($early, $late),
+            DateRange::inclusiveDays($late, $early)
+        );
+    }
+
+    public function test_month_and_year_boundaries_are_handled(): void
+    {
+        $this->assertSame(3, DateRange::inclusiveDays(new DateTime('2026-07-30'), new DateTime('2026-08-01')));
+        $this->assertSame(3, DateRange::inclusiveDays(new DateTime('2026-12-31'), new DateTime('2027-01-02')));
+        // 2028 ist ein Schaltjahr.
+        $this->assertSame(2, DateRange::inclusiveDays(new DateTime('2028-02-28'), new DateTime('2028-02-29')));
+    }
+}