[1.15.2] Opening a different container with the same itemstack

[NindyBun]

I have two gui's/containers one with 8 slots and the other with 15. My tool opens the former container whenever you press a keybind, but I want to open the latter using the same tool. Essentially, if I pressed a certain keybind, the 15 slot container supersedes the original 8 slot container, therefor my tool it's container gains 7 more slots while retaining whatever's in it's previous inventory.  

Is there a way to go about this?

 

https://github.com/NindyBun/TestMod

[ModMCdl]

I believe you could do this by simply detecting whatever key is being pressed when it goes to access the container. It used to be called a KeyInputEvent, but I'm unsure if it changed for 1.15. I'd imagine it would also benefit you to do this with a Forge event, and then just have the item call your GUI whenever either keybind is activated and the item is in hand. 

[Draco18s]

Oy vey.

This will always return true. As will this and this.

Use orElseThrow here, that's why it exists.

You know what Capabilities are and yet, you did this.

Your tool is effective on nothing.

This is an unchecked cast. Other mods may have items with an inventories too. This code will crash the server if you hold one of their inventory-capable items and use your keybind.