How to modify an ability when near a building?

Suppose that I want to modify the following ability:
- Tommy AoE heal has, by default, a healing radius of 10
- I want to modify Tommy AoE heal so that the healing radius increases to 20 while the unit is within 15 units of a constructed forward assembly

I've tried the following two implementations, but both of them failed (due to bugs)

1. There is an option to make a requirement check for proximity to a particular entity (e.g., a forward assembly). However, when I tried it, the check seemed to completely ignore whether the assembly has been fully constructed or not

2. I tried giving forward assemblies an "AoE enable"-aura (sort of like the emplacement aura). The intention was that while the Tommy ability is active while the Tommy is within the aura of a forward assembly, the healing radius doubles.

However, I couldn't find any requirement check for "Unit is affected by aura"/etc.

3. I went for the aura approach again, but this time, I made the aura award an invisible, non-permanent slot item "healing-token-enabler". While Tommies were under possession of the token, the healing radius would increase.

This seemed to work alright for a while, but after some testing, I noticed that it was possible to abuse a bug and make the Tommies retain that item permanently. (vet-gate style: reinforce the squad while they have the item, and kill the original members of the squad when it walked into the aura).

Is there any solution to this? Thx!

1. There is an option to make a requirement check for proximity to a particular entity (e.g., a forward assembly). However, when I tried it, the check seemed to completely ignore whether the assembly has been fully constructed or not

This is the way to go. If you add a required_constructionstate to the near_entity_requirement, it should work as intended!

Just in case somebody wants to try something similar, I found two ways to get around the problem.

1. Slot item approach:
- Make the token slot-item non-permanent
- Make sure that the aura "affects squads" flag is set to True

(I had the "affects squads" set to False, which meant that the non-permanent slot item was not getting deleted from the new entities).

2. (related) upgrade approach, in case you want abilities affecting other abilities
- Say you want ability B to alter its behaviour while ability A (toggle or modal) is active
- Create a token upgrade which does nothing (or copy aef medic_auto_heal_refresh)
- Put an add-upgrade (token) on self-start actions of ability A
- Put a remove-upgrade (token) on self-end actions of ability A
- Add a requirement action for the token on ability B
- This won't work for auras (since upgrades are permanent, unless explicitly removed)