period overlap in php

output.sh

$ ./bin/phpunit overlap_test.php
PHPUnit 5.0.8 by Sebastian Bergmann and contributors.

.............                                                     13 / 13 (100%)

Time: 140 ms, Memory: 3.50Mb

OK (13 tests, 13 assertions)

overlap.php

<?php

class Period
{
    public $startDate;
    public $endDate;

    public function __construct(\DateTime $startDate, \DateTime $endDate)
    {
        $this->startDate = $startDate;
        $this->endDate = $endDate;
    }

    public function overlap(Period $period)
    {
        return $this->endDate > $period->startDate && $this->startDate < $period->endDate;
    }
}

overlap_test.php

<?php

require __DIR__.'/vendor/autoload.php';
require __DIR__.'/overlap.php';

class PeriodTest extends \PHPUnit_Framework_TestCase
{
    protected static $reference;

    protected function setUp()
    {
        static::$reference = new \Period(new \DateTime('2015-11-16'), new \DateTime('2015-11-23'));
    }

    /**
     * @dataProvider overlapPeriod
     */
    public function testOverlap($period)
    {
        $this->assertTrue(static::$reference->overlap($period));
    }

    /**
     * @dataProvider doNotOverlapPeriod
     */
    public function testDoesNotOverlap($period)
    {
        $this->assertFalse(static::$reference->overlap($period));
    }

    public function doNotOverlapPeriod()
    {
        return [
            [new \Period(new \DateTime('2015-11-07'), new \DateTime('2015-11-13'))],
            [new \Period(new \DateTime('2015-11-25'), new \DateTime('2015-11-31'))],
            [new \Period(new \DateTime('2015-11-07'), new \DateTime('2015-11-16'))],
            [new \Period(new \DateTime('2015-11-23'), new \DateTime('2015-11-31'))],
        ];
    }

    public function overlapPeriod()
    {
        return [
            [new \Period(new \DateTime('2015-11-07'), new \DateTime('2015-11-18'))],
            [new \Period(new \DateTime('2015-11-18'), new \DateTime('2015-11-25'))],
            [new \Period(new \DateTime('2015-11-16'), new \DateTime('2015-11-18'))],
            [new \Period(new \DateTime('2015-11-16'), new \DateTime('2015-11-25'))],
            [new \Period(new \DateTime('2015-11-16'), new \DateTime('2015-11-23'))],
            [new \Period(new \DateTime('2015-11-07'), new \DateTime('2015-11-23'))],
            [new \Period(new \DateTime('2015-11-18'), new \DateTime('2015-11-23'))],
            [new \Period(new \DateTime('2015-11-18'), new \DateTime('2015-11-20'))],
            [new \Period(new \DateTime('2015-11-13'), new \DateTime('2015-11-25'))],
        ];
    }
}