Endermen that are in a minecart cannot teleport out of the minecart if attacked or shot at. They will make the teleportation sound as if they did teleport and they may disappear briefly but end up back in the minecart.

Steps to Reproduce:
1. Make a new Creative world.
2. Place down rails of any kind (more than one).
3. Place a normal minecart on the tracks.
4. Spawn an Enderman near the minecart and push it in if needed.
5. Shoot at the Enderman with a bow and observe how it attempts to teleport, but ends up right back in the minecart.