export const enum PatchFlags {
  TEXT = 1, // 动态文本
  CLASS = 1 << 1, // 2 动态class
  STYLE = 1 << 2, // 4 动态style
  PROPS = 1 << 3, // 8
  FULL_PROPS = 1 << 4, // 16
  HYDRATE_EVENTS = 1 << 5, // 32
  STABLE_FRAGMENT = 1 << 6, // 64
  KEYED_FRAGMENT = 1 << 7, // 128
  UNKEYED_FRAGMENT = 1 << 8, // 256
  NEED_PATCH = 1 << 9, // 512
  DYNAMIC_SLOTS = 1 << 10, // 1024
  DEV_ROOT_FRAGMENT = 1 << 11, // 2048
  HOISTED = -1,
  BAIL = -2
}

export const enum ShapeFlags {
  ELEMENT = 1,
  FUNCTIONAL_COMPONENT = 1 << 1, // 2
  STATEFUL_COMPONENT = 1 << 2, // 4
  TEXT_CHILDREN = 1 << 3, // 8
  ARRAY_CHILDREN = 1 << 4, // 16
  SLOTS_CHILDREN = 1 << 5, // 32
  TELEPORT = 1 << 6, // 64
  SUSPENSE = 1 << 7, // 128
  COMPONENT_SHOULD_KEEP_ALIVE = 1 << 8, // 256
  COMPONENT_KEPT_ALIVE = 1 << 9, // 512
  COMPONENT = ShapeFlags.STATEFUL_COMPONENT | ShapeFlags.FUNCTIONAL_COMPONENT // 4 | 2
}

export const enum SlotFlags {
  /**
   * Stable slots that only reference slot props or context state. The slot
   * can fully capture its own dependencies so when passed down the parent won't
   * need to force the child to update.
   */
  STABLE = 1,
  /**
   * Slots that reference scope variables (v-for or an outer slot prop), or
   * has conditional structure (v-if, v-for). The parent will need to force
   * the child to update because the slot does not fully capture its dependencies.
   */
  DYNAMIC = 2,
  /**
   * `<slot/>` being forwarded into a child component. Whether the parent needs
   * to update the child is dependent on what kind of slots the parent itself
   * received. This has to be refined at runtime, when the child's vnode
   * is being created (in `normalizeChildren`)
   */
  FORWARDED = 3
}