Improve factory timezone handling

src/Carbon/CarbonInterval.php

@@ -25,6 +25,8 @@
 use Carbon\Traits\Options;
 use Closure;
 use DateInterval;
+use DateTimeInterface;
+use DateTimeZone;
 use Exception;
 use ReflectionException;
 use ReturnTypeWillChange;
@@ -253,6 +255,22 @@ class CarbonInterval extends DateInterval implements CarbonConverterInterface
     protected $tzName;
 
     /**
+     * Set the instance's timezone from a string or object.
+     *
+     * @param \DateTimeZone|string $tzName
+     *
+     * @return static
+     */
+    public function setTimezone($tzName)
+    {
+        $this->tzName = $tzName;
+
+        return $this;
+    }
+
+    /**
+     * @internal
+     *
      * Set the instance's timezone from a string or object and add/subtract the offset difference.
      *
      * @param \DateTimeZone|string $tzName
@@ -1763,12 +1781,20 @@ public function toDateInterval()
     /**
      * Convert the interval to a CarbonPeriod.
      *
-     * @param array ...$params Start date, [end date or recurrences] and optional settings.
+     * @param DateTimeInterface|string|int ...$params Start date, [end date or recurrences] and optional settings.
      *
      * @return CarbonPeriod
      */
     public function toPeriod(...$params)
     {
+        if ($this->tzName) {
+            $tz = \is_string($this->tzName) ? new DateTimeZone($this->tzName) : $this->tzName;
+
+            if ($tz instanceof DateTimeZone) {
+                array_unshift($params, $tz);
+            }
+        }
+
         return CarbonPeriod::create($this, ...$params);
     }
 

src/Carbon/CarbonPeriod.php

@@ -28,6 +28,7 @@
 use DatePeriod;
 use DateTime;
 use DateTimeInterface;
+use DateTimeZone;
 use InvalidArgumentException;
 use Iterator;
 use JsonSerializable;
@@ -639,7 +640,11 @@ public function __construct(...$arguments)
         }
 
         foreach ($arguments as $argument) {
-            if ($this->dateInterval === null &&
+            $parsedDate = null;
+
+            if ($argument instanceof DateTimeZone) {
+                $this->setTimezone($argument);
+            } elseif ($this->dateInterval === null &&
                 (
                     \is_string($argument) && preg_match(
                         '/^(-?\d(\d(?![\/-])|[^\d\/-]([\/-])?)*|P[T0-9].*|(?:\h*\d+(?:\.\d+)?\h*[a-z]+)+)$/i',
@@ -648,13 +653,13 @@ public function __construct(...$arguments)
                     $argument instanceof DateInterval ||
                     $argument instanceof Closure
                 ) &&
-                $parsed = @CarbonInterval::make($argument)
+                $parsedInterval = @CarbonInterval::make($argument)
             ) {
-                $this->setDateInterval($parsed);
-            } elseif ($this->startDate === null && $parsed = Carbon::make($argument)) {
-                $this->setStartDate($parsed);
-            } elseif ($this->endDate === null && $parsed = Carbon::make($argument)) {
-                $this->setEndDate($parsed);
+                $this->setDateInterval($parsedInterval);
+            } elseif ($this->startDate === null && $parsedDate = $this->makeDateTime($argument)) {
+                $this->setStartDate($parsedDate);
+            } elseif ($this->endDate === null && ($parsedDate = $parsedDate ?? $this->makeDateTime($argument))) {
+                $this->setEndDate($parsedDate);
             } elseif ($this->recurrences === null && $this->endDate === null && is_numeric($argument)) {
                 $this->setRecurrences($argument);
             } elseif ($this->options === null && (\is_int($argument) || $argument === null)) {
@@ -1689,7 +1694,30 @@ public function __call($method, $parameters)
     }
 
     /**
-     * Set the instance's timezone from a string or object and add/subtract the offset difference.
+     * Set the instance's timezone from a string or object and apply it to start/end.
+     *
+     * @param \DateTimeZone|string $timezone
+     *
+     * @return static
+     */
+    public function setTimezone($timezone)
+    {
+        $this->tzName = $timezone;
+        $this->timezone = $timezone;
+
+        if ($this->startDate) {
+            $this->setStartDate($this->startDate->setTimezone($timezone));
+        }
+
+        if ($this->endDate) {
+            $this->setEndDate($this->endDate->setTimezone($timezone));
+        }
+
+        return $this;
+    }
+
+    /**
+     * Set the instance's timezone from a string or object and add/subtract the offset difference to start/end.
      *
      * @param \DateTimeZone|string $timezone
      *
@@ -1700,6 +1728,14 @@ public function shiftTimezone($timezone)
         $this->tzName = $timezone;
         $this->timezone = $timezone;
 
+        if ($this->startDate) {
+            $this->setStartDate($this->startDate->shiftTimezone($timezone));
+        }
+
+        if ($this->endDate) {
+            $this->setEndDate($this->endDate->shiftTimezone($timezone));
+        }
+
         return $this;
     }
 
@@ -2495,4 +2531,24 @@ private function orderCouple($first, $second): array
     {
         return $first > $second ? [$second, $first] : [$first, $second];
     }
+
+    private function makeDateTime($value): ?DateTimeInterface
+    {
+        if ($value instanceof DateTimeInterface) {
+            return $value;
+        }
+
+        if (\is_string($value)) {
+            $value = trim($value);
+
+            if (!preg_match('/^P[0-9T]/', $value) &&
+                !preg_match('/^R[0-9]/', $value) &&
+                preg_match('/[a-z0-9]/i', $value)
+            ) {
+                return Carbon::parse($value, $this->tzName);
+            }
+        }
+
+        return null;
+    }
 }

src/Carbon/Factory.php

@@ -11,6 +11,7 @@
 namespace Carbon;
 
 use Closure;
+use DateTimeInterface;
 use ReflectionMethod;
 
 /**
@@ -289,7 +290,13 @@ public function __call($name, $arguments)
                 return \in_array($parameter->getName(), ['tz', 'timezone'], true);
             });
 
-            if (\count($tzParameters)) {
+            if (isset($arguments[0]) && \in_array($name, ['instance', 'make', 'create', 'parse'], true)) {
+                if ($arguments[0] instanceof DateTimeInterface) {
+                    $settings['innerTimezone'] = $settings['timezone'];
+                } elseif (\is_string($arguments[0]) && date_parse($arguments[0])['is_localtime']) {
+                    unset($settings['timezone'], $settings['innerTimezone']);
+                }
+            } elseif (\count($tzParameters)) {
                 array_splice($arguments, key($tzParameters), 0, [$settings['timezone']]);
                 unset($settings['timezone']);
             }

src/Carbon/Traits/Creator.php

@@ -367,7 +367,7 @@ private static function createNowInstance($tz)
      */
     public static function create($year = 0, $month = 1, $day = 1, $hour = 0, $minute = 0, $second = 0, $tz = null)
     {
-        if (\is_string($year) && !is_numeric($year)) {
+        if (\is_string($year) && !is_numeric($year) || $year instanceof DateTimeInterface) {
             return static::parse($year, $tz ?: (\is_string($month) || $month instanceof DateTimeZone ? $month : null));
         }
 

src/Carbon/Traits/Date.php

@@ -1584,10 +1584,11 @@ public function setTimezone($value)
      */
     public function shiftTimezone($value)
     {
-        $offset = $this->offset;
-        $date = $this->setTimezone($value);
+        $dateTimeString = $this->format('Y-m-d H:i:s.u');
 
-        return $date->addRealMicroseconds(($offset - $date->offset) * static::MICROSECONDS_PER_SECOND);
+        return $this
+            ->setTimezone($value)
+            ->modify($dateTimeString);
     }
 
     /**

src/Carbon/Traits/Options.php

@@ -385,6 +385,10 @@ public function settings(array $settings)
             $this->locale(...$locales);
         }
 
+        if (isset($settings['innerTimezone'])) {
+            return $this->setTimezone($settings['innerTimezone']);
+        }
+
         if (isset($settings['timezone'])) {
             return $this->shiftTimezone($settings['timezone']);
         }

tests/Carbon/SettersTest.php

@@ -396,6 +396,9 @@ public function testShiftTimezone()
         $this->assertSame(21600, $d2->getTimestamp() - $d->getTimestamp());
         $this->assertSame('America/Toronto', $d2->tzName);
         $this->assertSame('10:53:12.321654', $d2->format('H:i:s.u'));
+
+        $d = Carbon::parse('2018-03-25 00:53:12.321654 America/Toronto')->shiftTimezone('Europe/Oslo');
+        $this->assertSame('2018-03-25 00:53:12.321654 Europe/Oslo', $d->format('Y-m-d H:i:s.u e'));
     }
 
     public function testTimezoneUsingString()

tests/CarbonImmutable/SettersTest.php

@@ -272,6 +272,9 @@ public function testShiftTimezone()
         $this->assertSame(21600, $d2->getTimestamp() - $d->getTimestamp());
         $this->assertSame('America/Toronto', $d2->tzName);
         $this->assertSame('10:53:12', $d2->format('H:i:s'));
+
+        $d = Carbon::parse('2018-03-25 00:53:12.321654 America/Toronto')->shiftTimezone('Europe/Oslo');
+        $this->assertSame('2018-03-25 00:53:12.321654 Europe/Oslo', $d->format('Y-m-d H:i:s.u e'));
     }
 
     public function testTimezoneUsingString()

tests/CarbonInterval/ToPeriodTest.php

@@ -46,4 +46,14 @@ public function provideToPeriodParameters(): Generator
                 '2018-05-14T17:30:00+00:00/PT30M/2018-05-14T18:00:00+02:00',
             ];
     }
+
+    public function testToDatePeriodWithTimezone(): void
+    {
+        $period = CarbonInterval::minutes(30)
+            ->setTimezone('Asia/Tokyo')
+            ->toPeriod('2021-08-14 00:00', '2021-08-14 02:00');
+
+        $this->assertSame('2021-08-14 00:00 Asia/Tokyo', $period->start->format('Y-m-d H:i e'));
+        $this->assertSame('2021-08-14 02:00 Asia/Tokyo', $period->end->format('Y-m-d H:i e'));
+    }
 }

tests/CarbonPeriod/CreateTest.php

@@ -314,7 +314,11 @@ public function testCreateFromBaseClasses()
         );
 
         $this->assertSame(
-            $this->standardizeDates(['2018-04-16', '2018-05-16', '2018-06-16']),
+            [
+                '2018-04-16 00:00:00 -04:00',
+                '2018-05-16 00:00:00 -04:00',
+                '2018-06-16 00:00:00 -04:00',
+            ],
             $this->standardizeDates($period)
         );
     }

tests/CarbonPeriod/SettersTest.php

@@ -425,4 +425,48 @@ public function testFluentSetters()
         $this->assertSame(20, $period->getDateInterval()->dayz);
         $this->assertSame($opt, $period->getOptions());
     }
+
+    public function testSetTimezone(): void
+    {
+        $period = CarbonPeriod::create(
+            '2018-03-25 00:00 America/Toronto',
+            'PT1H',
+            '2018-03-25 12:00 Europe/London'
+        )->setTimezone('Europe/Oslo');
+
+        $this->assertSame('2018-03-25 06:00 Europe/Oslo', $period->getStartDate()->format('Y-m-d H:i e'));
+        $this->assertSame('2018-03-25 13:00 Europe/Oslo', $period->getEndDate()->format('Y-m-d H:i e'));
+
+        $period = CarbonPeriod::create(
+            '2018-03-25 00:00 America/Toronto',
+            'PT1H',
+            5
+        )->setTimezone('Europe/Oslo');
+
+        $this->assertSame('2018-03-25 06:00 Europe/Oslo', $period->getStartDate()->format('Y-m-d H:i e'));
+        $this->assertNull($period->getEndDate());
+        $this->assertSame('2018-03-25 10:00 Europe/Oslo', $period->calculateEnd()->format('Y-m-d H:i e'));
+    }
+
+    public function testShiftTimezone(): void
+    {
+        $period = CarbonPeriod::create(
+            '2018-03-25 00:00 America/Toronto',
+            'PT1H',
+            '2018-03-25 12:00 Europe/London'
+        )->shiftTimezone('Europe/Oslo');
+
+        $this->assertSame('2018-03-25 00:00 Europe/Oslo', $period->getStartDate()->format('Y-m-d H:i e'));
+        $this->assertSame('2018-03-25 12:00 Europe/Oslo', $period->getEndDate()->format('Y-m-d H:i e'));
+
+        $period = CarbonPeriod::create(
+            '2018-03-26 00:00 America/Toronto',
+            'PT1H',
+            5
+        )->shiftTimezone('Europe/Oslo');
+
+        $this->assertSame('2018-03-26 00:00 Europe/Oslo', $period->getStartDate()->format('Y-m-d H:i e'));
+        $this->assertNull($period->getEndDate());
+        $this->assertSame('2018-03-26 04:00 Europe/Oslo', $period->calculateEnd()->format('Y-m-d H:i e'));
+    }
 }

tests/Factory/FactoryTest.php

@@ -107,5 +107,41 @@ public function testFactoryTimezone()
         $this->assertSame('2020-09-03 00:00:00.000000 America/Toronto', $factory->today()->format('Y-m-d H:i:s.u e'));
         $this->assertSame('2020-09-04 00:00:00.000000 America/Toronto', $factory->tomorrow()->format('Y-m-d H:i:s.u e'));
         $this->assertSame('2020-09-04 09:39:04.123456 America/Toronto', $factory->parse('2020-09-04 09:39:04.123456')->format('Y-m-d H:i:s.u e'));
+
+        $factory = new Factory([
+            'timezone' => 'Asia/Shanghai',
+        ]);
+
+        $baseDate = Carbon::parse('2021-08-01 08:00:00', 'UTC');
+
+        $date = $factory->createFromTimestamp($baseDate->getTimestamp());
+        $this->assertSame('2021-08-01T16:00:00+08:00', $date->format('c'));
+
+        $date = $factory->make('2021-08-01 08:00:00');
+        $this->assertSame('2021-08-01T08:00:00+08:00', $date->format('c'));
+
+        $date = $factory->make($baseDate);
+        $this->assertSame('2021-08-01T16:00:00+08:00', $date->format('c'));
+
+        $date = $factory->create($baseDate);
+        $this->assertSame('2021-08-01T16:00:00+08:00', $date->format('c'));
+
+        $date = $factory->parse($baseDate);
+        $this->assertSame('2021-08-01T16:00:00+08:00', $date->format('c'));
+
+        $date = $factory->instance($baseDate);
+        $this->assertSame('2021-08-01T16:00:00+08:00', $date->format('c'));
+
+        $date = $factory->make('2021-08-01 08:00:00+00:20');
+        $this->assertSame('2021-08-01T08:00:00+00:20', $date->format('c'));
+
+        $date = $factory->parse('2021-08-01T08:00:00Z');
+        $this->assertSame('2021-08-01T08:00:00+00:00', $date->format('c'));
+
+        $date = $factory->create('2021-08-01 08:00:00 UTC');
+        $this->assertSame('2021-08-01T08:00:00+00:00', $date->format('c'));
+
+        $date = $factory->make('2021-08-01 08:00:00 Europe/Paris');
+        $this->assertSame('2021-08-01T08:00:00+02:00', $date->format('c'));
     }
 }