Function resolveTransitionProps

packages/runtime-dom/src/components/Transition.ts:121–298

(
  rawProps: TransitionProps,
)

}

export function resolveTransitionProps(
  rawProps: TransitionProps,
): BaseTransitionProps<Element> {
  const baseProps: BaseTransitionProps<Element> = {}
  for (const key in rawProps) {
    if (!(key in DOMTransitionPropsValidators)) {
      ;(baseProps as any)[key] = (rawProps as any)[key]
    }
  }

  if (rawProps.css === false) {
    return baseProps
  }

  const {
    name = 'v',
    type,
    duration,
    enterFromClass = `${name}-enter-from`,
    enterActiveClass = `${name}-enter-active`,
    enterToClass = `${name}-enter-to`,
    appearFromClass = enterFromClass,
    appearActiveClass = enterActiveClass,
    appearToClass = enterToClass,
    leaveFromClass = `${name}-leave-from`,
    leaveActiveClass = `${name}-leave-active`,
    leaveToClass = `${name}-leave-to`,
  } = rawProps

  // legacy transition class compat
  const legacyClassEnabled =
    __COMPAT__ &&
    compatUtils.isCompatEnabled(DeprecationTypes.TRANSITION_CLASSES, null)
  let legacyEnterFromClass: string
  let legacyAppearFromClass: string
  let legacyLeaveFromClass: string
  if (__COMPAT__ && legacyClassEnabled) {
    const toLegacyClass = (cls: string) => cls.replace(/-from$/, '')
    if (!rawProps.enterFromClass) {
      legacyEnterFromClass = toLegacyClass(enterFromClass)
    }
    if (!rawProps.appearFromClass) {
      legacyAppearFromClass = toLegacyClass(appearFromClass)
    }
    if (!rawProps.leaveFromClass) {
      legacyLeaveFromClass = toLegacyClass(leaveFromClass)
    }
  }

  const durations = normalizeDuration(duration)
  const enterDuration = durations && durations[0]
  const leaveDuration = durations && durations[1]
  const {
    onBeforeEnter,
    onEnter,
    onEnterCancelled,
    onLeave,
    onLeaveCancelled,