fix: two tree move (inside the same parent) issues (#450)

* fix: two tree move (inside the same parent) issues

* chore: add release note

.changeset/lemon-maps-smash.md

@@ -0,0 +1,6 @@
+---
+"loro-crdt": patch
+"loro-wasm": patch
+---
+
+Fix tree move issues

crates/loro-internal/src/handler/tree.rs

@@ -518,7 +518,7 @@ impl TreeHandler {
             .ok_or(LoroTreeError::TreeNodeNotExist(other))?;
         let mut index = self.get_index_by_tree_id(&other).unwrap();
         if self.is_parent(target, parent)
-            && index > 1
+            && index >= 1
             && self.get_index_by_tree_id(&target).unwrap() < index
         {
             index -= 1;

crates/loro/src/lib.rs

@@ -1322,9 +1322,7 @@ impl LoroTree {
     /// tree.mov(root2, root).unwrap();
     /// ```
     pub fn mov<T: Into<Option<TreeID>>>(&self, target: TreeID, parent: T) -> LoroResult<()> {
-        let parent = parent.into();
-        let index = self.children_num(parent).unwrap_or(0);
-        self.handler.move_to(target, parent, index)
+        self.handler.mov(target, parent)
     }
 
     /// Move the `target` node to be a child of the `parent` node at the given index.

crates/loro/tests/loro_rust_test.rs

@@ -871,3 +871,22 @@ fn len_and_is_empty_inconsistency() {
     assert_eq!(map.len(), 0);
     assert!(map.is_empty());
 }
+
+#[test]
+fn test_tree_move() {
+    let doc = LoroDoc::new();
+    let tree = doc.get_tree("tree");
+    let root1 = tree.create(None).unwrap();
+    let node1 = tree.create(root1).unwrap();
+    let node2 = tree.create(root1).unwrap();
+    assert_eq!(tree.children(Some(root1)).unwrap(), vec![node1, node2]);
+    tree.mov_before(node2, node1).unwrap();
+    assert_eq!(tree.children(Some(root1)).unwrap(), vec![node2, node1]);
+    tree.mov_before(node2, node1).unwrap();
+    assert_eq!(tree.children(Some(root1)).unwrap(), vec![node2, node1]);
+
+    tree.mov_after(node2, node1).unwrap();
+    assert_eq!(tree.children(Some(root1)).unwrap(), vec![node1, node2]);
+    tree.mov_after(node2, node1).unwrap();
+    assert_eq!(tree.children(Some(root1)).unwrap(), vec![node1, node2]);
+}

loro-js/tests/tree.test.ts

@@ -182,6 +182,16 @@ describe("loro tree node", ()=>{
     });
 });
 
+describe("LoroTree", () => {
+  it ("move", () => {
+    const loro = new Loro();
+    const tree = loro.getTree("root");
+    const root = tree.createNode();
+    const child = tree.createNode(root.id);
+    tree.move(child.id, root.id);
+  })
+})
+
 function one_ms(): Promise<void> {
   return new Promise((resolve) => setTimeout(resolve, 1));
-}
+}