Function normalizePropsOptions

packages/runtime-core/src/componentProps.ts:510–616

(
  comp: ConcreteComponent,
  appContext: AppContext,
  asMixin = false,
)

const mixinPropsCache = new WeakMap<ConcreteComponent, NormalizedPropsOptions>()

export function normalizePropsOptions(
  comp: ConcreteComponent,
  appContext: AppContext,
  asMixin = false,
): NormalizedPropsOptions {
  const cache =
    __FEATURE_OPTIONS_API__ && asMixin ? mixinPropsCache : appContext.propsCache
  const cached = cache.get(comp)
  if (cached) {
    return cached
  }

  const raw = comp.props
  const normalized: NormalizedPropsOptions[0] = {}
  const needCastKeys: NormalizedPropsOptions[1] = []

  // apply mixin/extends props
  let hasExtends = false
  if (__FEATURE_OPTIONS_API__ && !isFunction(comp)) {
    const extendProps = (raw: ComponentOptions) => {
      if (__COMPAT__ && isFunction(raw)) {
        raw = raw.options
      }
      hasExtends = true
      const [props, keys] = normalizePropsOptions(raw, appContext, true)
      extend(normalized, props)
      if (keys) needCastKeys.push(...keys)
    }
    if (!asMixin && appContext.mixins.length) {
      appContext.mixins.forEach(extendProps)
    }
    if (comp.extends) {
      extendProps(comp.extends)
    }
    if (comp.mixins) {
      comp.mixins.forEach(extendProps)
    }
  }

  if (!raw && !hasExtends) {
    if (isObject(comp)) {
      cache.set(comp, EMPTY_ARR as any)
    }
    return EMPTY_ARR as any
  }

  if (isArray(raw)) {
    for (let i = 0; i < raw.length; i++) {
      if (__DEV__ && !isString(raw[i])) {
        warn(`props must be strings when using array syntax.`, raw[i])
      }
      const normalizedKey = camelize(raw[i])
      if (validatePropName(normalizedKey)) {
        normalized[normalizedKey] = EMPTY_OBJ
      }
    }
  } else if (raw) {
    if (__DEV__ && !isObject(raw)) {