PHPSecureSessionTest\HashTest::testHashEquals PHP Method

    public function testHashEquals()
    {
        $class = new ReflectionClass(SecureHandler::class);
        $method = $class->getMethod('hash_equals');
        $method->setAccessible(true);
        $numBytes = 1048576;
        $expected = random_bytes($numBytes);
        $actual = $expected;
        $actual[0] = chr(ord($actual[0]) + 1 % 256);
        // Compare two almost identical string (the first byte is different)
        $start = microtime(true);
        $equal = $method->invoke($this->secureHandler, $expected, $actual);
        $execTime1 = microtime(true) - $start;
        $this->assertFalse($equal);
        // Compare the same random string
        $start = microtime(true);
        $equal = $method->invoke($this->secureHandler, $expected, $expected);
        $execTime2 = microtime(true) - $start;
        $this->assertTrue($equal);
        // The difference bewteen the executtion times should be less than 30%
        $this->assertGreaterThan(0.7, $execTime1 / $execTime2);
        $this->assertLessThan(1.3, $execTime1 / $execTime2);
    }