add tests

tests/Pest.php

@@ -0,0 +1,59 @@
+<?php
+
+// phpcs:disable PSR1.Files.SideEffects
+
+declare(strict_types=1);
+
+/*
+|--------------------------------------------------------------------------
+| Test Case
+|--------------------------------------------------------------------------
+|
+| The closure you provide to your test functions is always bound to a specific PHPUnit test
+| case class. By default, that class is "PHPUnit\Framework\TestCase". Of course, you may
+| need to change it using the "uses()" function to bind a different classes or traits.
+|
+*/
+
+use Tests\TestCase;
+
+\uses(TestCase::class)->group('unit')->in('Unit');
+\uses(TestCase::class)->group('feature')->in('Feature');
+
+/*
+|--------------------------------------------------------------------------
+| Expectations
+|--------------------------------------------------------------------------
+|
+| When you're writing tests, you often need to check that values meet certain conditions. The
+| "expect()" function gives you access to a set of "expectations" methods that you can use
+| to assert different things. Of course, you may extend the Expectation API at any time.
+|
+*/
+
+\expect()->extend('toBeOne', function () {
+    return $this->toBe(1);
+});
+
+\expect()->extend('toMatchCallback', function (callable $callback, string $message = '') {
+    $result = $callback($this->value);
+    \expect($result)->toBeTrue($message);
+
+    return $this;
+});
+
+/*
+|--------------------------------------------------------------------------
+| Functions
+|--------------------------------------------------------------------------
+|
+| While Pest is very powerful out-of-the-box, you may have some testing code specific to your
+| project that you don't want to repeat in every file. Here you can also expose helpers as
+| global functions to help you to reduce the number of lines of code in your test files.
+|
+*/
+
+function getExamplePath(string $filename): string
+{
+    return __DIR__ . "/data/examples/{$filename}";
+}