test(DateHelper): add integration tests for date parsing and formatting

This commit introduces integration tests for the DatesHelper class,
ensuring correct functionality for date parsing, range verification,
and RFC3339 formatting.

tests/Integration/Shared/Helpers/DateHelperTest.php

@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+use Illuminate\Support\Facades\Date;
+use Shared\Helpers\DatesHelper;
+
+covers(DatesHelper::class);
+
+afterEach(function () {
+    \Mockery::close();
+    Date::clearResolvedInstances();
+});
+
+describe('Date Helper', function (): void {
+    it('can parse a date time', function (): void {
+        // GIVEN
+        $date = '2025-12-25 12:10:23';
+
+        // WHEN
+        $result = DatesHelper::parseDateTime($date);
+
+        // THEN
+        expect($result)->toBeInstanceOf(\DateTimeInterface::class)
+            ->and($result->format('Y-m-d'))->toBe('2025-12-25')
+            ->and($result->format('H:i:s'))->toBe('12:10:23');
+    });
+
+    it('can verify a date is in between', function (): void {
+        // GIVEN
+        $now  = Date::create(2025, 12, 25, 12, 0, 0);
+        $from = Date::createFromDate(2025, 12, 24);
+        $to   = Date::createFromDate(2025, 12, 26);
+
+        // WHEN
+        Date::setTestNow($now);
+        $result = DatesHelper::isIn($from, $to);
+
+        // THEN
+        expect($result)->toBeTruthy();
+    });
+
+    it('can verify a date is not in between', function (): void {
+        // GIVEN
+        $now  = Date::create(2025, 12, 25, 12, 0, 0);
+        $from = Date::createFromDate(2025, 12, 26);
+        $to   = Date::createFromDate(2025, 12, 27);
+
+        // WHEN
+        Date::setTestNow($now);
+        $result = DatesHelper::isIn($from, $to);
+
+        // THEN
+        expect($result)->toBeFalse();
+    });
+
+    it('can format a date time to RFC3339', function (): void {
+        // GIVEN
+        $date = '2025-12-25 12:10:23';
+
+        // WHEN
+        $result = DatesHelper::toRfc3339($date);
+
+        // THEN
+        expect($result)->toBe('2025-12-25T12:10:23+00:00');
+    });
+});