insertBefore()

in packages/core/src/models/TreeNode.ts [598:625]

• 28 lines of code
• 5 McCabe index (conditional complexity)

  insertBefore(...nodes: TreeNode[]) {
    const parent = this.parent
    if (nodes.some((node) => node.contains(this))) return []
    if (parent?.children?.length) {
      const originSourceParents = nodes.map((node) => node.parent)
      const newNodes = this.resetNodesParent(nodes, parent)
      if (!newNodes.length) return []
      return this.triggerMutation(
        new InsertBeforeEvent({
          originSourceParents,
          target: this,
          source: newNodes,
        }),
        () => {
          parent.children = parent.children.reduce((buf, node) => {
            if (node === this) {
              return buf.concat(newNodes).concat([node])
            } else {
              return buf.concat([node])
            }
          }, [])
          return newNodes
        },
        []
      )
    }
    return []
  }