Fix scratchpad fullscreen behavior and crash

When setting fullscreen on a hidden scratchpad container, there was a
check to see if there was an existing fullscreen container on the
workspace so it could be fullscreen disabled first. Since the workspace
is NULL, it would cause a SIGSEGV. This adds a NULL check to avoid the
crash.

This also changes the behavior of how fullscreen is handled when adding
a container to the scratchpad or changing visibility of a scratchpad
container to match i3's. The behavior is as follows:
- When adding a container to the scratchpad or hiding a container back
  into the scratchpad, there is an implicit fullscreen disable
- When setting fullscreen on a container that is hidden in the
  scratchpad, it will be fullscreen when shown (and fullscreen disabled
  when hidden as stated above)
- When setting fullscreen global on a container that is hidden in the
  scratchpad, it will be shown immediately as fullscreen global. The
  container is not moved to a workspace and remains in the
  scratchpad. The container will be visible until fullscreen disabled
  or killed. Since the container is in the scratchpad, running
  `scratchpad show` or `move container to scratchpad` will have no
  effect

This also changes `container_replace` to transfer fullscreen and
scratchpad status.

1 files changed, 8 insertions, 0 deletions

diff --git a/sway/tree/node.c b/sway/tree/node.c
index dcab1c9b..ffa7f2cc 100644
--- a/sway/tree/node.c
+++ b/sway/tree/node.c
@@ -142,11 +142,19 @@ list_t *node_get_children(struct sway_node *node) {
 }
 
 bool node_has_ancestor(struct sway_node *node, struct sway_node *ancestor) {
+	if (ancestor->type == N_ROOT && node->type == N_CONTAINER &&
+			node->sway_container->fullscreen_mode == FULLSCREEN_GLOBAL) {
+		return true;
+	}
 	struct sway_node *parent = node_get_parent(node);
 	while (parent) {
 		if (parent == ancestor) {
 			return true;
 		}
+		if (ancestor->type == N_ROOT && parent->type == N_CONTAINER &&
+				parent->sway_container->fullscreen_mode == FULLSCREEN_GLOBAL) {
+			return true;
+		}
 		parent = node_get_parent(parent);
 	}
 	return false;