sort the tf tree output, and output all the parent-children pairs- ne…

…ed to handle the case of disconnected trees next

tf_roslibrust/src/bin/tree.rs

@@ -23,6 +23,8 @@ fn print_tree(
 
     match parent_to_children.get(parent) {
         Some(children) => {
+            let mut children = children.iter().collect::<Vec<_>>();
+            children.sort();
             for child in children {
                 let _ = print_tree(parent_to_children, child, level + 1);
             }
@@ -69,10 +71,18 @@ async fn main() -> Result<(), anyhow::Error> {
     tokio::time::sleep(tokio::time::Duration::from_secs(1)).await;
 
     {
+        // TODO(lucasw) make tf listener stop listening
         let buffer = listener.buffer.read().unwrap();
         let root = buffer.get_root()?;
         println!("\n");
         let parent_to_children = buffer.get_parent_to_children();
+        {
+            let mut keys_sorted = parent_to_children.keys().collect::<Vec<_>>();
+            keys_sorted.sort();
+            for parent in keys_sorted {
+                println!("{parent}: {:?}", parent_to_children.get(parent).unwrap());
+            }
+        }
         let _ = print_tree(&parent_to_children, &root, 0);
     }