您确定要编写面向对象的代码吗?

我们的PHP开发人员为使用OOP语言编写而感到自豪(您可以在此处轻松地用C#,Java或其他OOP语言替换PHP)。每个空缺都包含对OOP知识的要求。在每次采访中,他们都会询问有关SOLID或OOP的三头鲸的问题。但是归根结底,我们只是让类充满了过程。OOP很少,通常在库代码中。



一个典型的Web应用程序是ORM实体类,它们包含数据库中某一行的数据,而控制器(或服务-没关系)包含处理这些数据的过程。面向对象的程序设计是关于拥有自己数据的对象,并且不将其提供给其他代码进行处理。一个很好的说明就是一个聊天中提出的一个问题:“如何改进此代码?”



private function getWorkingTimeIntervals(CarbonPeriod $businessDaysPeriod, array $timeRanges): array
{
    $workingTimeIntervals = [];
    foreach ($businessDaysPeriod as $date) {
        foreach ($timeRanges as $time) {
            $workingTimeIntervals[] = [
                'start' => Carbon::create($date->format('Y-m-d') . ' ' . $time['start']),
                'end' => Carbon::create($date->format('Y-m-d') . ' ' . $time['end'])
            ];
        }
    }

    return $workingTimeIntervals;
}

/**
 *    
 *
 * @param array $workingTimeIntervals
 * @param array $events
 * @return array
 */
private function removeEventsFromWorkingTime(array $workingTimeIntervals, array $events): array
{
    foreach ($workingTimeIntervals as $n => &$interval) {
        foreach ($events as $event) {
            $period = CarbonPeriod::create($interval['start'], $interval['end']);
            if ($period->overlaps($event['start_date'], $event['end_date'])) {
                if ($interval['start'] <= $event['start_date'] && $interval['end'] <= $event['end_date']) {
                    $interval['end'] = $event['start_date'];
                } elseif ($interval['start'] >= $event['start_date'] && $interval['end'] >= $event['end_date']) {
                    $interval['start'] = $event['end_date'];
                } elseif ($interval['start'] <= $event['start_date'] && $interval['end'] >= $event['end_date']) {
                    $interval['start'] = $event['start_date'];
                    $interval['end'] = $event['end_date'];
                } else {
                    unset($workingTimeIntervals[$n]);
                }
            }
        }
    }

    return $workingTimeIntervals;
}


. () (), . , . — ( ) , . , , . , , .



unit- . . ( ). .



class Interval
{
    //    PHP 7.4
    public DateTimeImmutable $start;
    public DateTimeImmutable $end;
}


DateTimeImmutable .



— .

, , , — .



unit-. . :



class Interval
{
    public DateTimeImmutable $start;
    public DateTimeImmutable $end;

    public function __construct(DateTimeImmutable $start, DateTimeImmutable $end)
    {
        $this->start = $start;
        $this->end = $end;
    }
}


PHPUnit- :



use App\Interval;
use PHPUnit\Framework\TestCase;

class IntervalTest extends TestCase
{
    private DateTimeImmutable $today;
    private DateTimeImmutable $yesterday;
    private DateTimeImmutable $tomorrow;

    protected function setUp(): void
    {
        $this->today = new DateTimeImmutable();
        $this->yesterday = $this->today->add(\DateInterval::createFromDateString("-1 day"));
        $this->tomorrow = $this->today->add(\DateInterval::createFromDateString("1 day"));

        parent::setUp();
    }

    public function testValidDates()
    {
        $interval = new Interval($this->yesterday, $this->today);

        $this->assertEquals($this->yesterday, $interval->start);
        $this->assertEquals($this->today, $interval->end);
    }

    public function testInvalidDates()
    {
        $this->expectException(\InvalidArgumentException::class);

        new Interval($this->today, $this->yesterday);
    }
}


, . , testValidDates, . , testInvalidDates, . , :



Failed asserting that exception of type "InvalidArgumentException" is thrown.


:



class Interval
{
    public DateTimeImmutable $start;
    public DateTimeImmutable $end;

    public function __construct(DateTimeImmutable $start, DateTimeImmutable $end)
    {
        if ($start > $end) {
            throw new \InvalidArgumentException("Invalid date interval");
        }

        $this->start = $start;
        $this->end = $end;
    }
}


. PHP, null . . , , . Interval . ? unit- . , . . , , isEmpty .



class Interval
{
    public DateTimeImmutable $start;
    public DateTimeImmutable $end;

    public function __construct(DateTimeImmutable $start, DateTimeImmutable $end)
    {
        if ($start > $end) {
            throw new \InvalidArgumentException("Invalid date interval");
        }

        $this->start = $start;
        $this->end = $end;
    }

    public function isEmpty(): bool
    {
        return $this->start->getTimestamp() == $this->end->getTimestamp();
    }
}

class IntervalTest extends TestCase
{
    //...

    public function testNonEmpty()
    {
        $interval = new Interval($this->yesterday, $this->today);

        $this->assertFalse($interval->isEmpty());
    }

    public function testEmpty()
    {
        $interval = new Interval($this->today, $this->today);

        $this->assertTrue($interval->isEmpty());
    }
}


. ['start'=>,'end'=>], . ! , . , :



-  08:00 - 12:00
-  13:00 - 17:00
  08:00 - 12:00
  13:00 - 17:00
...


, :



 :
-  08:00 - 09:00
-  16:00 - 17:00
  13:00 - 17:00

:
-  09:00 - 12:00
-  13:00 - 16:00
  08:00 - 12:00
...


Interval:



$period = CarbonPeriod::create($interval['start'], $interval['end']);
if ($period->overlaps($event['start_date'], $event['end_date'])) {
    if ($interval['start'] <= $event['start_date'] && $interval['end'] <= $event['end_date']) {
        $interval['end'] = $event['start_date'];
    } elseif ($interval['start'] >= $event['start_date'] && $interval['end'] >= $event['end_date']) {
        $interval['start'] = $event['end_date'];
    } elseif ($interval['start'] <= $event['start_date'] && $interval['end'] >= $event['end_date']) {
        $interval['start'] = $event['start_date'];
        $interval['end'] = $event['end_date'];
    } else {
        unset($workingTimeIntervals[$n]);
    }
}


Interval: remove(Interval $other) , . :



private function removeEventsFromWorkingTime($workingTimeIntervals, $events): array
{
    foreach ($workingTimeIntervals as $n => $interval) {
        foreach ($events as $event) {
            $interval->remove($event);

            if ($interval->isEmpty()) {
                unset($workingTimeIntervals[$n]);
            }
        }
    }

    return $workingTimeIntervals;
}


. . , , ! , . . , .



, $other .





class IntervalRemoveTest extends TestCase
{
    private DateTimeImmutable $minus10Days;
    private DateTimeImmutable $today;
    private DateTimeImmutable $yesterday;
    private DateTimeImmutable $tomorrow;
    private DateTimeImmutable $plus10Days;

    protected function setUp(): void
    {
        $this->today = new DateTimeImmutable();
        $this->yesterday = $this->today->sub(\DateInterval::createFromDateString("1 day"));
        $this->tomorrow = $this->today->add(\DateInterval::createFromDateString("1 day"));

        $this->minus10Days = $this->today->sub(\DateInterval::createFromDateString("10 day"));
        $this->plus10Days = $this->today->add(\DateInterval::createFromDateString("10 day"));

        parent::setUp();
    }

    public function testDifferent()
    {
        $interval = new Interval($this->minus10Days, $this->yesterday);

        $interval->remove(new Interval($this->tomorrow, $this->plus10Days));

        $this->assertEquals($this->minus10Days, $interval->start);
        $this->assertEquals($this->yesterday, $interval->end);
    }
}


, , .





class IntervalRemoveTest extends TestCase
{
    public function testFullyCovered()
    {
        $interval = new Interval($this->yesterday, $this->tomorrow);

        $interval->remove(new Interval($this->minus10Days, $this->plus10Days));

        $this->assertTrue($interval->isEmpty());
    }

    public function testFullyCoveredWithCommonStart()
    {
        $interval = new Interval($this->yesterday, $this->tomorrow);

        $interval->remove(new Interval($this->yesterday, $this->plus10Days));

        $this->assertTrue($interval->isEmpty());
    }

    // and testFullyCoveredWithCommonEnd()
}


, :





?





?! ! remove ! , :



} elseif ($interval['start'] <= $event['start_date'] && $interval['end'] >= $event['end_date']) {
        $interval['start'] = $event['start_date'];
        $interval['end'] = $event['end_date'];


.



, . , , . . , . , , . , , , . , , ! . .



IntervalCollection, :



class Interval
{
    public DateTimeImmutable $start;
    public DateTimeImmutable $end;

    public function __construct(DateTimeImmutable $start, 
                                DateTimeImmutable $end)
    {
        if ($start > $end) {
            throw new \InvalidArgumentException(
                                "Invalid date interval");
        }

        $this->start = $start;
        $this->end = $end;
    }

    public function isEmpty(): bool
    {
        return $this->start === $this->end;
    }

    /**
     * @param Interval $other
     * @return Interval[]
     */
    public function remove(Interval $other)
    {
        if ($this->start >= $other->end 
                || $this->end <= $other->start) return [$this];

        if ($this->start >= $other->start 
                && $this->end <= $other->end) return [];

        if ($this->start < $other->start 
                && $this->end > $other->end) return [
            new Interval($this->start, $other->start),
            new Interval($other->end, $this->end),
        ];

        if ($this->start === $other->start) {
            return [new Interval($other->end, $this->end)];
        }

        return [new Interval($this->start, $other->start)];
    }
}

/** @mixin Interval[] */
class IntervalCollection extends \ArrayIterator
{
    public function diff(IntervalCollection $other)
            : IntervalCollection
    {
        /** @var Interval[] $items */
        $items = $this->getArrayCopy();
        foreach ($other as $interval) {
            $newItems = [];
            foreach ($items as $ourInterval) {
                array_push($newItems, 
                ...$ourInterval->remove($interval));
            }
            $items = $newItems;
        }

        return new self($items);
    }
}


IntervalCollection — , . Interval, , .



https://github.com/adelf/intervals-example. , IntervalCollection::diff . , . . unit-.



, - coupling ( ), . private:



class Interval
{
    private DateTimeImmutable $start;
    private DateTimeImmutable $end;

    // methods
}


这可以通过添加样式方法来完成,print()这将有助于我们以所需的格式提取间隔数据,但将完全关闭从外部处理间隔数据的功能。但这绝对是另一篇文章的主题。




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