Fixed bug #65768: DateTimeImmutable::diff does not work

This commit also prevents user classes from directly implementing
DateTimeInterface, because ext/date relies on classes implementing
it to support certain internal structures.

1 files changed, 36 insertions, 0 deletions

diff --git a/tests/classes/bug65768.phpt b/tests/classes/bug65768.phpt
new file mode 100644
index 0000000000..17ec93cf24
--- /dev/null
+++ b/tests/classes/bug65768.phpt
@@ -0,0 +1,36 @@
+--TEST--
+Bug #65768: date_diff accepts only DateTime instance even though docs say about DateTimeInterface
+--INI--
+date.timezone=Europe/London
+--FILE--
+<?php
+
+$dt1 = new DateTime("2010-10-20");
+$dti1 = new DateTimeImmutable("2010-10-25");
+$dti2 = new DateTimeImmutable("2010-10-28");
+
+$diff1 = $dt1->diff($dti1);
+echo $diff1->y, " ", $diff1->m, " ", $diff1->d, " ",
+     $diff1->h, " ", $diff1->i, " ", $diff1->s, "\n";
+
+$diff2 = $dti1->diff($dti2);
+echo $diff2->y, " ", $diff2->m, " ", $diff2->d, " ",
+     $diff2->h, " ", $diff2->i, " ", $diff2->s, "\n";
+
+$diff3 = date_diff($dt1, $dti2);
+echo $diff3->y, " ", $diff3->m, " ", $diff3->d, " ",
+     $diff3->h, " ", $diff3->i, " ", $diff3->s, "\n";
+
+class cdt1 extends DateTime implements DateTimeInterface {}
+
+class cdt2 extends DateTimeImmutable implements DateTimeInterface {}
+
+class cdt3 implements DateTimeInterface {}
+
+?>
+--EXPECTF--
+0 0 5 0 0 0
+0 0 3 0 0 0
+0 0 8 0 0 0
+
+Fatal error: DateTimeInterface can't be implemented by user classes in %sbug65768.php on line %d