Flaky tests

EnvChecker.php

<?php

namespace App;

use App\Exceptions\UnknownEnvKey;
use Dotenv\Dotenv;

class EnvChecker
{
    protected $requiredKeys;

    protected $optionalKeys;

    protected $dotenv = null;

    protected $array = [];

    /**
     * A list of keys that are mandatory for the .env file
     *
     * @param  array  $array
     */
    public function requiredKeys($array): static
    {
        $this->requiredKeys = $array;

        return $this;
    }

    /**
     * A list of keys that are optional for the .env file
     *
     * @param [type] $array
     */
    public function optionalKeys($array): static
    {
        $this->optionalKeys = $array;

        return $this;
    }

    /**
     * Get the value of a key from our .env file
     *
     * @param  string  $key
     */
    public function value($key)
    {
        return $this->array[$key];
    }

    /**
     * Parse the contents of .env file and throw exceptions if unknown or missing keys
     */
    public function parseFile(string $filename): static
    {
        $dir = dirname($filename);
        $file = basename($filename);

        $this->dotenv = Dotenv::createImmutable($dir, $file);
        $this->array = $this->dotenv->load();

        return $this
            ->checkForUnknownKeys()
            ->checkForMissingKeys();
    }

    private function checkForMissingKeys(): static
    {
        $this->dotenv->required($this->requiredKeys);

        return $this;
    }

    private function checkForUnknownKeys(): static
    {
        $allKnown = array_merge($this->requiredKeys, $this->optionalKeys);
        foreach ($this->array as $key => $value) {
            if (! in_array($key, $allKnown)) {
                throw new UnknownEnvKey($key);
            }
        }

        return $this;
    }
}

EnvCheckerTest.php

<?php

namespace App\Tests\Feature;

use App\EnvChecker;
use App\Exceptions\UnknownEnvKey;
use App\Tests\TestbenchTestCase;

class EnvCheckerTest extends TestbenchTestCase
{
    // use \Illuminate\Foundation\Testing\DatabaseMigrations;
    // use \Illuminate\Foundation\Testing\LazilyRefreshDatabase;
    use \Illuminate\Foundation\Testing\WithoutMiddleware;

    protected $filename;

    public function setUp(): void
    {
        parent::setUp();
        $this->filename = __DIR__.'/../Fixtures/myconfig';
    }

    public function test_Can_parse_environment_file()
    {
        $content = <<<'TXT'
            ABCD=123
            DEF=456
            TXT;
        file_put_contents($this->filename, $content);

        $checker = (new EnvChecker)
            ->requiredKeys([
                'ABCD',
            ])
            ->optionalKeys([
                'DEF',
            ]);
        $checker->parseFile($this->filename);

        $this->assertEquals('123', $checker->value('ABCD'));
        $this->assertEquals('456', $checker->value('DEF'));
        unlink($this->filename);
    }

    public function test_Can_detect_unknown_environment_keys()
    {
        $content = <<<'TXT'
            UNKNOWN=123
            DEF=456
            TXT;
        file_put_contents($this->filename, $content);

        $this->expectException(UnknownEnvKey::class);
        $checker = (new EnvChecker)
            ->requiredKeys([])
            ->optionalKeys([
                'DEF',
            ]);
        $checker->parseFile($this->filename);
        unlink($this->filename);
    }

    public function test_Can_detect_missing_mandatory_environment_keys()
    {
        $content = <<<'TXT'
            DEF=456
            TXT;
        file_put_contents($this->filename, $content);

        $this->expectException(\Dotenv\Exception\ValidationException::class);
        (new EnvChecker)
            ->requiredKeys([
                'ABCD',
            ])
            ->optionalKeys([
                'DEF',
            ])
            ->parseFile($this->filename);

        unlink($this->filename);
    }
}