FLIP Animation not applied when first item spliced

[crutchcorn]

Version

3.0.4

Reproduction link

https://codepen.io/crutchcorn/pen/ZEpbZKX

Steps to reproduce

Take the example from:

https://v3.vuejs.org/guide/transitions-list.html#list-move-transitions

That's at this link:

https://codepen.io/team/Vue/pen/373b4429eb5769ae2e6d097fd954fd08

Change the remove method to match:

      this.items.splice(0, 1)

What is expected?

The first item in the array is removed and an animation smooths out the other items moving into the first spot

What is actually happening?

It jerkily moves the items to the first index

[crutchcorn]

Whoops! This is the repo for Vue 2! My bad. Re-filed here:

vuejs/core#2712