"function" selector

So basically, this would be a target selector, similar to dx, hasitem, and family, etc. However, what this one does, is tests for the state of players, or mobs.

Examples:
/testfor @e[function=moving]
Would test for anyone that is moving

/testfor @e[function={health=21..}]

Would test for anyone that has more than 20 health (via golden apple)

/testfor @e[function=jumping,sneaking,rightClicking]

Would test for anyone who is jumping, sneaking, and pressing their respective "use" button simultaneously

A small list of different functions:

- moving : Would test if the target is in motion

- idle : Would test if the target is not in motion

- swimming : Would test if the target has sprinted underwater

- jumping

- rightClick

- leftClick

- sprinting

All self explanatory

I think this would be an amazing idea for Minecraft, both Bedrock & Java!