Crash Block Minecraft PC and Mac

Put the summary of the bug you're having here
Crash Block Minecraft PC and Mac
What I expected to happen was...:
Describe what you thought should happen here I Thought Nothing was going to happen

What actually happened was...:
Describe what happened here I was trying some commands out (/setblock) then i typed in /setblock~~~piston_head 6
then when i left clicked the block i crashed I was making a video while that happened here is the video link: https://www.youtube.com/watch?v=EGUyxDNF_SQ#start=0:00;end=5:43;cycles=-1;autoreplay=false;showoptions=false
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here I started playing Minecraft
2. ... I Tested some commands
3. ... I Crashed Because of the Crash Block