Context
I put a saddle on a pig, then I gave him a nametag by right-clicking. This caused me to mount him and made disappear the nametag from my inventory. The pig was named.
What happened
By right-clicking a second time, the nametag came back in my inventory but the pig was still named.
What I expected
The nametag shouldn't have come back.
Probable cause
It might be caused by a conflict between two actions lead by a one command (right click).
Also it looks like server protection. You know, when you place a block where you are not allowed to, the block seems consumed but you get it back when right clicking anywhere.
Note about affected version
It happened in vanilla 1.7.2 but I couldn't choose it in the box above.
Duplicate of MC-19033 - If you have not, please use the search function in the future, to see if your bug has already been submitted. If you could not find the original report, please comment with the keywords you searched for.