<transition> API changes

[yyx990803]

• Transition class name adjustments [Rendered]

  • Rename the v-enter transition class to v-enter-from
  • Rename the v-leave transition class to v-leave-from

• Using <transition> as component's root will no longer trigger transitions when the component is toggled from the outside. [Rendered]

[CyberAP]

What would be the best way to refactor such code regarding we can no longer use v-if?

<TransitionExpand v-if="user">
  <UserInfo :user="user" />
</TransitionExpand>

user is a required prop and <UserInfo> component is not valid until it receives user.

If we refactor it like this we would get an error:

<TransitionExpand :visible="Boolean(user)">
  <UserInfo :user="user" /> <!-- UserInfo is rendered despite not being visible -->
</TransitionExpand>

Should we write v-if for slot contents as well now? Would that trigger a transition?

<TransitionExpand :visible="Boolean(user)">
  <UserInfo v-if="user" :user="user" />
</TransitionExpand>

[robertmoura]

You'd probably just do it the normal way:

<TransitionExpand>
    <UserInfo :user="user" v-if="user" />
</TransitionExpand>

[yyx990803]

This RFC is now in final comments stage. An RFC in final comments stage means that:

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