[MCM-591] [1.11] Killing a rideable entity respawns its rider, even if that rider was killed previously in the same tick.

Partner Rank:

Partner Team Reporting:

Everbloom Studios

Verification builds and Platforms:

1.10.0.10

Summary:

When a rideable entity is killed, its rider can be successfully targeted by commands such as /kill earlier in that tick, but the /kill command fails to kill the entity.

Impact:

This breaks The Enderman Heists, and is a regression from previous versions.

Repro Steps:

Download "The Enderman Heists" from the store, and enable cheats while creating the world.
Switch to creative via /gamemode 1
Run the following command: /tp 106 41 130
Observe the nearby enderman walking around the driveway.
Give yourself a command block via: /give @s command_block
Place an unconditional, needs redstone impulse command block with the command /kill @e[type=pig]
Place a conditional, always active chain command block in front of the impulse block so they form a chain with the command /kill @e[type=zombie]
Place a redstone block next to the impulse command block.
Observe the issue.

Observed Results:

The nearby enderman's body is killed leaving behind the head. Endermen are made up of two entities, the pig head riding the zombie body. Even though the pig kill command ran first and was successful, the pig (head) still was not killed due to the zombie (body) being killed.

Expected Results:

The entire nearby enderman is killed, body and head.

Regression Builds:

1.11.0.9