Add test for TTL expiration with fragmented memory

Author: madmajestro

package.xml

@@ -73,6 +73,7 @@
     <file name="apc_023.phpt" role="test" />
     <file name="apc_024.phpt" role="test" />
     <file name="apc_025.phpt" role="test" />
+    <file name="apc_026.phpt" role="test" />
     <file name="apc_099.phpt" role="test" />
     <file name="apc54_014.phpt" role="test" />
     <file name="apc54_018.phpt" role="test" />

tests/apc_026.phpt

@@ -0,0 +1,58 @@
+--TEST--
+Test TTL expiration with fragmented memory
+--SKIPIF--
+<?php
+require_once(__DIR__ . '/skipif.inc');
+if (!function_exists('apcu_inc_request_time')) die('skip APC debug build required');
+?>
+--INI--
+apc.enabled=1
+apc.enable_cli=1
+apc.use_request_time=1
+apc.ttl=1
+apc.shm_size=1M
+--FILE--
+<?php
+
+apcu_store("long_ttl", 123456789, 100);
+apcu_store("dummy", str_repeat('x', 11000));
+apcu_inc_request_time(2);
+
+// Fill the cache
+$i = 1;
+while (apcu_exists("dummy")) {
+    apcu_store("key_small_" . $i, $i, 3);
+    apcu_store("key_large_" . $i, str_repeat('x', 10000), 1);
+
+    $i++;
+}
+
+// Expire all large entries
+apcu_inc_request_time(2);
+
+// This insertion should trigger an expunge which expires all large entries
+var_dump(apcu_store("next_large_entry", str_repeat('x', 10000), 1));
+var_dump(apcu_fetch("next_large_entry") === str_repeat('x', 10000));
+
+// Check fragmented state (small entries are present, large entries are not present)
+var_dump(apcu_fetch("key_small_1"));
+var_dump(apcu_fetch("key_large_1"));
+
+// Expire all small entries
+apcu_inc_request_time(2);
+
+// This entry should trigger an expunge which expires all small entries.
+// This solves fragmentation which allows this entry to be stored without a full cache wipe.
+var_dump(apcu_store("very_large_entry", str_repeat('x', 20000), 1));
+var_dump(apcu_fetch("very_large_entry") === str_repeat('x', 20000));
+var_dump(apcu_fetch("long_ttl"));
+
+?>
+--EXPECT--
+bool(true)
+bool(true)
+int(1)
+bool(false)
+bool(true)
+bool(true)
+int(123456789)