test: Ensure timezone is reliable in tests

Author: pl-github

phpunit.xml.dist

@@ -20,4 +20,8 @@
             <directory>src</directory>
         </include>
     </source>
+
+    <php>
+        <ini name="date.timezone" value="UTC" />
+    </php>
 </phpunit>

tests/Convert/AsDateTimeImmutableTest.php

@@ -32,28 +32,28 @@ public function testConvertsStrings(): void
 
     public function testConvertsStringables(): void
     {
-        $result = asDateTimeImmutable(new StringableString('2010-09-08T07:06:05+02:00'));
+        $result = asDateTimeImmutable(new StringableString('2010-09-08T07:06:05+00:00'));
 
         self::assertInstanceOf(DateTimeImmutable::class, $result);
-        self::assertSame('2010-09-08T07:06:05+02:00', $result->format('c'));
+        self::assertSame('2010-09-08T07:06:05+00:00', $result->format('c'));
     }
 
     public function testConvertsDateTimeImmutableWithSameTimeZone(): void
     {
         $dateTimeZone = asDateTimeImmutable(new DateTimeImmutable())->getTimezone();
 
-        $result = asDateTimeImmutable(new DateTimeImmutable('2010-09-08T07:06:05+02:00', $dateTimeZone));
+        $result = asDateTimeImmutable(new DateTimeImmutable('2010-09-08T07:06:05+00:00', $dateTimeZone));
 
         self::assertInstanceOf(DateTimeImmutable::class, $result);
-        self::assertSame('2010-09-08T07:06:05+02:00', $result->format('c'));
+        self::assertSame('2010-09-08T07:06:05+00:00', $result->format('c'));
     }
 
     public function testConvertsDateTimeImmutableWithDifferentTimeZone(): void
     {
         $result = asDateTimeImmutable(new DateTimeImmutable('2010-09-08T07:06:05+02:00'));
 
         self::assertInstanceOf(DateTimeImmutable::class, $result);
-        self::assertSame('2010-09-08T07:06:05+02:00', $result->format('c'));
+        self::assertSame('2010-09-08T05:06:05+00:00', $result->format('c'));
     }
 
     public function testDoesNotTouchNull(): void