Path incorrectly calculated when moving nodes to different parent levels #28
Description
Version: v4.5.0-rc01
Description:
When moving a node from one parent to a different parent level, the library incorrectly calculates the new path, resulting in
malformed paths that cause subsequent operations to fail with "Source node not found" errors.
Steps to Reproduce:
1. Create a tree with nested nodes using LTree path notation
2. Configure tree with idMember="path", pathMember="path", and orderMember="sortOrder"
3. Move a node from a nested parent (e.g., 1.1.3 under parent 1.1) to root level (parent 1)
4. Observe the path becomes 1.1.1.3 instead of expected 1.5 or similar
Example Data:
let data = [
{ id: '1', path: '1', title: 'Root Folder', type: 'folder', sortOrder: 10 },
{ id: '1.1', path: '1.1', title: 'My Folder', type: 'folder', sortOrder: 10, isDraggable: true },
{ id: '1.1.1', path: '1.1.1', title: 'Playlist 1', type: 'playlist', sortOrder: 10, isDraggable: true },
{ id: '1.1.2', path: '1.1.2', title: 'Playlist 2', type: 'playlist', sortOrder: 20, isDraggable: true },
{ id: '1.1.3', path: '1.1.3', title: 'My Folder1', type: 'folder', sortOrder: 30, isDraggable: true },
{ id: '1.2', path: '1.2', title: 'Playlist 3', type: 'playlist', sortOrder: 30, isDraggable: true }
];
Tree Configuration:
<Tree
{data}
treeId="tree-component-example"
idMember="path"
pathMember="path"
displayValueMember="title"
orderMember="sortOrder"
shouldDisplayDebugInformation={true}
beforeDropCallback={beforeDrop}
onNodeDrop={handleDrop}
/>
Console Output:
// Initial drag - path is correct
[Tree] _onNodeDragStart - node: 1.1.3
// First move within same parent - works correctly
refreshSiblings: Re-sorted 3 children under "1.1":
0: {path: '1.1.1', sortOrder: 10}
1: {path: '1.1.3', sortOrder: 15}
2: {path: '1.1.2', sortOrder: 20}
[Tree] Auto-moved node: {success: true}
// Second move to different parent - path becomes WRONG
[Tree] _onNodeDragStart - node: 1.1.3
refreshSiblings: Re-sorted 5 children under "1":
0: {path: '1.1.1.3', sortOrder: 0} ← INCORRECT PATH!
1: {path: '1.1', sortOrder: 10}
2: {path: '1.2', sortOrder: 30}
3: {path: '1.3', sortOrder: 40}
4: {path: '1.4', sortOrder: 50}
[Tree] Auto-moved node: {success: true}
// Third move attempt - fails because tree has wrong path
[Tree] _onNodeDragStart - node: 1.1.1.3 ← Now using WRONG path
[Tree] Auto-moved node: {success: false, error: 'Source node not found: 1.1.1.3'}
Expected Behavior:
When moving node 1.1.3 from parent 1.1 to parent 1 (above node 1.3), the new path should be calculated as 1.5 or similar valid
root-level path, not 1.1.1.3.
Actual Behavior:
The path becomes 1.1.1.3 - an invalid path that appears to concatenate parts of the old path incorrectly. Subsequent drag
operations fail with "Source node not found" errors because the tree's internal state has the wrong path.
Workaround:
Currently blocking cross-parent moves in beforeDropCallback to prevent the bug:
function beforeDrop(dropNode, draggedNode, position) {
const draggedParent = draggedNode.parentPath;
const dropParent = position === 'child' ? dropNode.path : dropNode.parentPath;
if (draggedParent !== dropParent) {
console.warn('Cross-parent move blocked - library bug');
return false;
}
return true;
}
Environment:
- Browser: Chrome/Firefox
- SvelteKit Version: 5
- @keenmate/svelte-treeview: v4.5.0-rc01
- Node: (your version)
Additional Notes:
- Moving nodes WITHIN the same parent works correctly
- Dropping nodes INTO folders (position='child') may have the same issue
- The bug appears to be in the path recalculation logic in ltree.svelte.js or the refreshSiblings function
- Setting unique sortOrder values for siblings does not fix the issue
---
Copy-Paste Ready Version for GitHub:
### Bug: Path incorrectly calculated when moving nodes between hierarchy levels
**Version:** v4.5.0-rc01
When moving a node from one parent to a different parent level, the library incorrectly calculates the new path, causing "Source
node not found" errors.
**Reproduce:**
1. Move node `1.1.3` (child of `1.1`) to root level (sibling of `1.1`)
2. Path becomes `1.1.1.3` instead of expected root-level path like `1.5`
3. Subsequent operations fail with "Source node not found: 1.1.1.3"
**Console output:**
refreshSiblings: Re-sorted 5 children under "1":
0: {path: '1.1.1.3', sortOrder: 0} ← WRONG!
**Config:**
```svelte
<Tree
{data}
idMember="path"
pathMember="path"
orderMember="sortOrder"
beforeDropCallback={beforeDrop}
onNodeDrop={handleDrop}
/>
Expected: Path should be 1.5 or similar valid root path
Actual: Path becomes 1.1.1.3 (malformed)
Workaround: Block cross-parent moves in beforeDropCallback
Moving within same parent works correctly.