Merge branch 'EtixLabs-hover-bugfix'

Author: fritz-c

src/utils/tree-data-utils.js

@@ -610,7 +610,8 @@ function addNodeAtDepthAndIndex({
     }
 
     // If the current position is the only possible place to add, add it
-    if (currentIndex >= minimumTreeIndex - 1 || (isLastChild && !node.children)) {
+    if (currentIndex >= minimumTreeIndex - 1
+      || (isLastChild && !(node.children && node.children.length))) {
         if (typeof node.children === 'function') {
             throw new Error('Cannot add to children defined by a function');
         } else {
@@ -740,7 +741,7 @@ function addNodeAtDepthAndIndex({
  * Insert a node into the tree at the given depth, after the minimum index
  *
  * @param {!Object[]} treeData - Tree data
- * @param {!number} depth - The depth to insert the node at
+ * @param {!number} depth - The depth to insert the node at (the first level of the array being depth 0)
  * @param {!number} minimumTreeIndex - The lowest possible treeIndex to insert the node at
  * @param {!Object} newNode - The node to insert into the tree
  * @param {boolean=} ignoreCollapsed - Ignore children of nodes without `expanded` set to `true`

src/utils/tree-data-utils.test.js

@@ -1350,6 +1350,45 @@ describe('insertNode', () => {
             path: [1, 3, 4],
         });
     });
+
+    it('should work with nodes with an empty children array', () => {
+        expect(insertNode({
+            treeData: [
+                {
+                    expanded: true,
+                    children: [
+                        {
+                            expanded: true,
+                            children: [
+                                { children: [] },
+                            ],
+                        },
+                    ],
+                },
+            ],
+            newNode: { key: 'new' },
+            depth: 2,
+            minimumTreeIndex: 2,
+            getNodeKey: keyFromTreeIndex,
+        })).toEqual({
+            treeData: [
+                {
+                    expanded: true,
+                    children: [
+                        {
+                            expanded: true,
+                            children: [
+                                { key: 'new' },
+                                { children: [] },
+                            ],
+                        },
+                    ],
+                },
+            ],
+            treeIndex: 2,
+            path: [0, 1, 2],
+        });
+    });
 });
 
 describe('walk', () => {