SimpleTest: Fatal error: Call to undefined function dmemcache_delete() in tests/memcache.test on line 338 and other errors

Also this error appears after fixing the first one:

Fatal error: Call to undefined function memcache_wildcards() in tests/memcache.test on line 341

When fixing two above errors in the following way:

--- tests/memcache.test	(revision 6440)
+++ tests/memcache.test	(working copy)
@@ -335,6 +335,8 @@
     $this->assertFalse($this->checkCacheExists('test_cid_clear1', $this->default_value), 'The cache was cleared successfully.');
     // Delete the wildcard manually to simulate an eviction.
     $wildcard = '.wildcard-' . 'test_';
+    module_load_include('inc', 'memcache', 'memcache');
+    module_load_include('inc', 'memcache', 'dmemcache');
     dmemcache_delete($wildcard, $this->default_bin);

I've the other error:

 Fatal error: Cannot redeclare cache_get() in memcache.inc on line 33

so now I'm confused.

Workaround patch to not breaking the whole Simpletest with Fatal error.

There are some other errors like:

Call to undefined function dmemcache_key()	PHP Fatal error	memcache_test.module	28
Call to undefined function dmemcache_key()	PHP Fatal error	memcache_test.module	43

but within the Simpletest test, so at least doesn't stop the whole instance of SimpleTests.

Patch fixes as well errors in #4, but ignoring execution of memcache_wildcards()

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