If you use /tp @p @e[type=pig,limit=1] in 1.13-pre7, you will be teleported to the pig correctly.
Can confirm in 1.13-pre7. But drinking after dying will give the effect. It disappears when respawn.
Press F3+T may fix this.
Can confirm in 1.13-pre7.
Minecraftlive
If you use /tp @p @e[type=pig,limit=1] in 1.13-pre7, you will be teleported to the pig correctly.