What I was doing at the time of bug

I was testing the new combat in the combat test release and was swinging ingame to see if there were any changes to the hit cooldown. I then wanted to see if the damage on weapons had been increased on weapons so I went in creative and started killing sheep and naturally spawned animals. Not too long after I had killed a couple of animals I decided to spawn in zombies using zombies eggs and kill them. ** 
Describe what you thought should happen here

The Bug

after spawning the zombie mobs in I tried killing them with my sword but found that I could not swing at all ingame. I was able to interact with the Minecraft UI just fine. but I could not swing my fist (empty or holding an item) ingame at all.  C

What I tried to do to fix bug

1. Changed attack/destroy keybind to a key on my keyboard (Failed)

2. Saved and exited the world than starting it again (Failed)

3. Switching my game mode back to survival (Failed)

4. Creating completely new worlds (Failed)

Steps to Reproduce:
1.Log on with cheats and bonus cheats
2. Go in creative
3. Give yourself 1x diamond sword                                                                                                     4.Spawn in zombies with zombie eggs                                                                                            5. right-click click on  a zombie than Attempt to kill said zombies with a diamond sword

6. Enjoy not being able to harm any mobs in the game! Myabe turkey will find the game non-violent now