test(Pagination): add unit tests for Pagination value object

tests/Unit/Shared/PaginationTest.php

@@ -0,0 +1,61 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Unit\Shared;
+
+use Shared\Pagination;
+
+covers(Pagination::class);
+
+describe('Pagination Value Object', function (): void {
+    it('can be created from page and page size', function (): void {
+        // GIVEN
+        $page = 2;
+        $size = 20;
+
+        // WHEN
+        $pagination = Pagination::ofPage($page, $size);
+
+        // THEN
+        expect($pagination->from())->toBe(20)
+            ->and($pagination->to())->toBe(39)
+            ->and($pagination->pageSize())->toBe(20)
+            ->and($pagination->pageNumber())->toBe(2);
+    });
+
+    it('can be created from offset and limit', function (): void {
+        // GIVEN
+        $offset = 20;
+        $limit  = 10;
+
+        // WHEN
+        $pagination = Pagination::ofOffsetAndLimit($offset, $limit);
+
+        // THEN
+        expect($pagination->from())->toBe(20)
+            ->and($pagination->to())->toBe(29)
+            ->and($pagination->pageSize())->toBe(10)
+            ->and($pagination->pageNumber())->toBe(3);
+    });
+
+    it('can be created using first page', function (): void {
+        // GIVEN
+        $pageSize = 15;
+
+        // WHEN
+        $pagination = Pagination::firstPage($pageSize);
+
+        // THEN
+        expect($pagination->from())->toBe(0)
+            ->and($pagination->to())->toBe(14)
+            ->and($pagination->pageSize())->toBe(15)
+            ->and($pagination->pageNumber())->toBe(1);
+    });
+
+    it('throws exception for invalid page size or negative index', function (): void {
+        // GIVEN / WHEN / THEN
+        expect(fn () => Pagination::ofPage(0, 10))
+            ->toThrow(\InvalidArgumentException::class);
+    });
+});