Steps to reproduce:
1. Create a small 2x1 bath.
2. Place water in one corner
3. Place TNT in other corner
4. Ignite TNT.
Observe as entiny appears to clip through block.

2 option.
1. Create a 3x2 bath.
2. On one side place 3 block of water
3. On the other side, place a single block.
4. Place TNT block in the middle of water side, and ignite it.
Entiny starts clipping, then teleports back before exploding.