diff -up php-5.2.17/ext/tidy/tidy.c.bug-54682 php-5.2.17/ext/tidy/tidy.c
--- php-5.2.17/ext/tidy/tidy.c.bug-54682	2012-01-12 11:42:01.000000000 +0700
+++ php-5.2.17/ext/tidy/tidy.c	2012-01-12 11:42:17.000000000 +0700
@@ -1178,7 +1178,7 @@ static PHP_FUNCTION(tidy_diagnose)
 {
 	TIDY_FETCH_OBJECT;
 
-	if (tidyRunDiagnostics(obj->ptdoc->doc) >= 0) {
+	if (tidyStatus(obj->ptdoc->doc) != 0 && tidyRunDiagnostics(obj->ptdoc->doc) >= 0) {
 		tidy_doc_update_properties(obj TSRMLS_CC);
 		RETURN_TRUE;
 	}