fix(intl): fix circular dependency (#1302)

Author: brendt

packages/intl/src/MessageFormat/Functions/DateTimeFunction.php

@@ -2,8 +2,7 @@
 
 namespace Tempest\Intl\MessageFormat\Functions;
 
-use DateTime;
-use Tempest\DateTime\DateTime as TempestDateTime;
+use Tempest\DateTime\DateTime;
 use Tempest\Intl\MessageFormat\Formatter\FormattedValue;
 use Tempest\Intl\MessageFormat\FormattingFunction;
 use Tempest\Support\Arr;
@@ -14,12 +13,11 @@ final class DateTimeFunction implements FormattingFunction
 
     public function format(mixed $value, array $parameters): FormattedValue
     {
-        if (class_exists(TempestDateTime::class)) {
-            $datetime = TempestDateTime::parse($value);
-        } else {
-            $datetime = new DateTime($value);
+        if (! class_exists(DateTime::class)) {
+            throw new \RuntimeException('`tempest/datetime` is required to use the `datetime` function.');
         }
 
+        $datetime = DateTime::parse($value);
         $formatted = $datetime->format(Arr\get_by_key($parameters, 'pattern'));
 
         return new FormattedValue($value, $formatted);

packages/intl/tests/FormatterTest.php

@@ -4,6 +4,7 @@
 
 use PHPUnit\Framework\Attributes\TestWith;
 use PHPUnit\Framework\TestCase;
+use Tempest\DateTime\DateTime;
 use Tempest\Intl\IntlConfig;
 use Tempest\Intl\Locale;
 use Tempest\Intl\MessageFormat\Formatter\FormattedValue;
@@ -51,13 +52,17 @@ public function test_placeholder_variable(): void
 
     public function test_format_datetime_function_and_parameters(): void
     {
+        if (! class_exists(DateTime::class)) {
+            $this->markTestSkipped('`tempest/datetime` is needed for this test.');
+        }
+
         $formatter = new MessageFormatter([new DateTimeFunction()]);
 
         $value = $formatter->format(<<<'TXT'
-        Today's year is {$today :datetime pattern=|Y|}.
+        Today is {$today :datetime pattern=|yyyy/MM/dd|}.
         TXT, today: '2024-01-01');
 
-        $this->assertSame('Today\'s year is 2024.', $value);
+        $this->assertSame('Today is 2024/01/01.', $value);
     }
 
     public function test_format_number_function(): void