PopTest\Log\LogTest::testErr PHP Method

    public function testErr()
    {
        $l = new Logger(new File(__DIR__ . '/../tmp/app.log'));
        $l->err('Test log message');
        $this->assertTrue(file_exists(__DIR__ . '/../tmp/app.log'));
        $this->assertGreaterThan(0, filesize(__DIR__ . '/../tmp/app.log'));
        unlink(__DIR__ . '/../tmp/app.log');
    }