# HG changeset patch
# User rubidium <rubidium@openttd.org>
# Date 2014-08-16 10:20:15
# Node ID c4d9fa63836ab078d723845531605c029d514bab
# Parent  95c0c9aca14adcab49cc2117163e862aff5ad1bd

(svn r26736) -Fix [Script]: infinite loop (by scripts; always returning the same item) when sorted by item in descending order by oddly constructed FindNext that uses forward iterators. Simply use the same code as the ascending item sort but use the reverse iterator instead of the forward. Also do this same trick for the descending value sort even though I couldn't trigger the problem there

diff --git a/src/script/api/script_list.cpp b/src/script/api/script_list.cpp
--- a/src/script/api/script_list.cpp
+++ b/src/script/api/script_list.cpp
@@ -151,9 +151,9 @@ public:
  */
 class ScriptListSorterValueDescending : public ScriptListSorter {
 private:
-	ScriptList::ScriptListBucket::iterator bucket_iter;    ///< The iterator over the list to find the buckets.
-	ScriptList::ScriptItemList *bucket_list;               ///< The current bucket list we're iterator over.
-	ScriptList::ScriptItemList::iterator bucket_list_iter; ///< The iterator over the bucket list.
+	ScriptList::ScriptListBucket::reverse_iterator bucket_iter;    ///< The iterator over the list to find the buckets.
+	ScriptList::ScriptItemList *bucket_list;                       ///< The current bucket list we're iterator over.
+	ScriptList::ScriptItemList::reverse_iterator bucket_list_iter; ///< The iterator over the bucket list.
 
 public:
 	/**
@@ -172,13 +172,11 @@ public:
 		this->has_no_more_items = false;
 
 		/* Go to the end of the bucket-list */
-		this->bucket_iter = this->list->buckets.begin();
-		for (size_t i = this->list->buckets.size(); i > 1; i--) this->bucket_iter++;
+		this->bucket_iter = this->list->buckets.rbegin();
 		this->bucket_list = &(*this->bucket_iter).second;
 
 		/* Go to the end of the items in the bucket */
-		this->bucket_list_iter = this->bucket_list->begin();
-		for (size_t i = this->bucket_list->size(); i > 1; i--) this->bucket_list_iter++;
+		this->bucket_list_iter = this->bucket_list->rbegin();
 		this->item_next = *this->bucket_list_iter;
 
 		int32 item_current = this->item_next;
@@ -203,18 +201,15 @@ public:
 			return;
 		}
 
-		if (this->bucket_list_iter == this->bucket_list->begin()) {
-			if (this->bucket_iter == this->list->buckets.begin()) {
+		this->bucket_list_iter++;
+		if (this->bucket_list_iter == this->bucket_list->rend()) {
+			this->bucket_iter++;
+			if (this->bucket_iter == this->list->buckets.rend()) {
 				this->bucket_list = NULL;
 				return;
 			}
-			this->bucket_iter--;
 			this->bucket_list = &(*this->bucket_iter).second;
-			/* Go to the end of the items in the bucket */
-			this->bucket_list_iter = this->bucket_list->begin();
-			for (size_t i = this->bucket_list->size(); i > 1; i--) this->bucket_list_iter++;
-		} else {
-			this->bucket_list_iter--;
+			this->bucket_list_iter = this->bucket_list->rbegin();
 		}
 		this->item_next = *this->bucket_list_iter;
 	}
@@ -315,7 +310,7 @@ public:
  */
 class ScriptListSorterItemDescending : public ScriptListSorter {
 private:
-	ScriptList::ScriptListMap::iterator item_iter; ///< The iterator over the items in the map.
+	ScriptList::ScriptListMap::reverse_iterator item_iter; ///< The iterator over the items in the map.
 
 public:
 	/**
@@ -333,8 +328,7 @@ public:
 		if (this->list->items.empty()) return 0;
 		this->has_no_more_items = false;
 
-		this->item_iter = this->list->items.begin();
-		for (size_t i = this->list->items.size(); i > 1; i--) this->item_iter++;
+		this->item_iter = this->list->items.rbegin();
 		this->item_next = (*this->item_iter).first;
 
 		int32 item_current = this->item_next;
@@ -352,12 +346,12 @@ public:
 	 */
 	void FindNext()
 	{
-		if (this->item_iter == this->list->items.end()) {
+		if (this->item_iter == this->list->items.rend()) {
 			this->has_no_more_items = true;
 			return;
 		}
-		this->item_iter--;
-		if (this->item_iter != this->list->items.end()) item_next = (*this->item_iter).first;
+		this->item_iter++;
+		if (this->item_iter != this->list->items.rend()) item_next = (*this->item_iter).first;
 	}
 
 	int32 Next()