Fix T98909: Outliner - "Show Hierarchy" only shows one level

Error in a4a7af47326.

To allow deleting tree elements while iterating, the new iterators would
get needed data out of the tree element before calling the iterator
callback. This included the info if the element is open or collapsed. So
if the callback would open or collapse elements, the iterator wouldn't
respect that change. Luckily the way the open/collapsed state is stored,
we can still query it after the callback is executed, without having to
access the (possibly freed) tree element.

2 files changed, 5 insertions, 4 deletions

diff --git a/source/blender/editors/space_outliner/tree/tree_iterator.cc b/source/blender/editors/space_outliner/tree/tree_iterator.cc
index 85ff9e6437e..8d2b0b21433 100644
--- a/source/blender/editors/space_outliner/tree/tree_iterator.cc
+++ b/source/blender/editors/space_outliner/tree/tree_iterator.cc
@@ -43,13 +43,14 @@ void all_open(const SpaceOutliner &space_outliner,
 {
   LISTBASE_FOREACH_MUTABLE (TreeElement *, element, &subtree) {
     /* Get needed data out in case element gets freed. */
-    const bool is_open = TSELEM_OPEN(element->store_elem, &space_outliner);
+    const TreeStoreElem *tselem = TREESTORE(element);
     const ListBase subtree = element->subtree;
 
     visitor(element);
-    /* Don't access element from now on, it may be freed. */
+    /* Don't access element from now on, it may be freed. Note that the open/collapsed state may
+     * also have been changed in the visitor callback. */
 
-    if (is_open) {
+    if (TSELEM_OPEN(tselem, &space_outliner)) {
       all_open(space_outliner, subtree, visitor);
     }
   }
diff --git a/source/blender/editors/space_outliner/tree/tree_iterator.hh b/source/blender/editors/space_outliner/tree/tree_iterator.hh
index e3b3c90eaad..de5bcd2c462 100644
--- a/source/blender/editors/space_outliner/tree/tree_iterator.hh
+++ b/source/blender/editors/space_outliner/tree/tree_iterator.hh
@@ -26,7 +26,7 @@ void all(const ListBase &subtree, VisitorFn visitor);
 
 /**
  * Preorder (meaning depth-first) traversal of all elements not part of a collapsed sub-tree.
- * Freeing the currently visited element in \a visitor is fine.
+ * Freeing the currently visited element in \a visitor is fine (but not its tree-store element).
  */
 void all_open(const SpaceOutliner &, VisitorFn visitor);
 void all_open(const SpaceOutliner &, const ListBase &subtree, VisitorFn visitor);