[intl] fix leak when iterating IntlBreakIterator parts iterators

Iterating getPartsIterator() leaked memory on every loop because the
IntlPartsIterator held a counted self-reference through its embedded
zend_object_iterator's wrapping_obj, so refcount destruction could
never complete, and zoi_with_current_dtor() never released the retained
current element either. zoi_with_current_dtor() now invalidates the
current element and the parts iterator no longer addrefs itself
(wrapping_obj stays UNDEF as in the plain BreakIterator iterator),
making teardown deterministic; the string enumeration iterator keeps
its self-reference because move_forward/rewind need the owner for error
handling.

Author: iliaal

NEWS

@@ -25,6 +25,8 @@ PHP                                                                        NEWS
     wrong argument in error messages. (Weilin Du)
 
 - Intl:
+  . Fixed a memory leak when iterating IntlBreakIterator::getPartsIterator()
+    results. (iliaal)
   . Fixed a double-free when IntlGregorianCalendar construction fails after
     the ICU constructor adopts the TimeZone. (iliaal)
   . Fixed bug GH-23094 (NumberFormatter parsing offsets use UTF-16 positions

ext/intl/breakiterator/breakiterator_iterators.cpp

@@ -242,7 +242,7 @@ void IntlIterator_from_BreakIterator_parts(zval *break_iter_zv,
 	ii->iterator->index = 0;
 
 	((zoi_with_current*)ii->iterator)->destroy_it = _breakiterator_parts_destroy_it;
-	ZVAL_OBJ_COPY(&((zoi_with_current*)ii->iterator)->wrapping_obj, Z_OBJ_P(object));
+	ZVAL_UNDEF(&((zoi_with_current*)ii->iterator)->wrapping_obj);
 	ZVAL_UNDEF(&((zoi_with_current*)ii->iterator)->current);
 
 	((zoi_break_iter_parts*)ii->iterator)->bio = Z_INTL_BREAKITERATOR_P(break_iter_zv);

ext/intl/common/common_enum.cpp

@@ -37,6 +37,7 @@ void zoi_with_current_dtor(zend_object_iterator *iter)
 	zoi_with_current *zoiwc = (zoi_with_current*)iter;
 	zval_ptr_dtor(&zoiwc->wrapping_obj);
 	ZVAL_UNDEF(&zoiwc->wrapping_obj);
+	iter->funcs->invalidate_current(iter);
 }
 
 U_CFUNC zend_result zoi_with_current_valid(zend_object_iterator *iter)

ext/intl/tests/breakiter_parts_iterator_current_leak.phpt

@@ -0,0 +1,23 @@
+--TEST--
+IntlPartsIterator must not retain the current element after destruction
+--SKIPIF--
+<?php if (!extension_loaded('intl')) die('skip intl extension not available'); ?>
+--INI--
+memory_limit=64M
+--FILE--
+<?php
+$bi = IntlBreakIterator::createWordInstance('en');
+$bi->setText('hello world foo bar baz');
+$m0 = memory_get_usage();
+for ($i = 0; $i < 300000; $i++) {
+    foreach ($bi->getPartsIterator() as $v) {
+        break;
+    }
+}
+$m1 = memory_get_usage();
+var_dump($m1 - $m0 < 4 * 1024 * 1024);
+?>
+
+--EXPECT--
+bool(true)
+