Fixed most crashes

graphene/src/document.rs

@@ -140,6 +140,10 @@ impl Document {
 		path
 	}
 
+	pub fn is_folder(&self, path: &[LayerId]) -> bool {
+		return self.folder(path).is_ok();
+	}
+
 	// Determines which layer is closer to the root, if path_a return true, if path_b return false
 	// Answers the question: Is A closer to the root than B?
 	pub fn layer_closer_to_root(&self, path_a: &[u64], path_b: &[u64]) -> bool {

graphene/src/layers/folder.rs

@@ -101,6 +101,11 @@ impl Folder {
 		Some(&mut self.layers[pos])
 	}
 
+	pub fn folder_contains(&self, id: LayerId) -> bool {
+		log::debug!("For {:?} Folder does contain {:?}", id, self.layer_ids.contains(&id));
+		self.layer_ids.contains(&id)
+	}
+
 	pub fn position_of_layer(&self, layer_id: LayerId) -> Result<usize, DocumentError> {
 		self.layer_ids.iter().position(|x| *x == layer_id).ok_or_else(|| DocumentError::LayerNotFound([layer_id].into()))
 	}