function getSlotDirectivesOnChildren(node) {
  /** @type {VDirective[][]} */
  const groups = []
  for (const group of utils.iterateChildElementsChains(node)) {
    const slotDirs = group
      .map((childElement) =>
        childElement.name === 'template'
          ? utils.getDirective(childElement, 'slot')
          : null
      )
      .filter(utils.isDef)
    if (slotDirs.length > 0) {
      groups.push(slotDirs)
    }
  }

  return groups
}
Get all `v-slot` directives on the children of a given element.
@param {VElement} node The VElement node to check.
@returns {VDirective[][]}
The array of the group of `v-slot` directives.
The group bundles `v-slot` directives of element sequence which is connected
by `v-if`/`v-else-if`/`v-else`.