Allow modification of options.keep for pf2e.preReroll and pf2e.reroll

[7H3LaughingMan]

• Closes Pass keep as an object to the hooks pf2e.preReroll and pf2e.reroll so it can be modified #21494

[stwlam]

Isn't this in the roll?

[7H3LaughingMan]

Isn't this in the roll?

The system uses options.keep from the parameters of rerollFromMessage to determine which roll to keep, the problem is that since it just passes it as options.keep it's a primitive type so Javascript is just passing around a copy of the data instead of a reference which means it can't be modified.

[stwlam]

roll.options.keep

[7H3LaughingMan]

The system doesn't use that to determine which roll to keep, it uses options.keep from the parameters.

pf2e/src/module/system/check/check.ts

Lines 536 to 544 in dddda45

	// Check if we should keep the old roll instead.
	if (
	(options.keep === "higher" && oldRoll.total > newRoll.total) ||
	(options.keep === "lower" && oldRoll.total < newRoll.total)
	) {
	// If so, switch the css classes and keep the old roll.
	[oldRollClass, newRollClass] = [newRollClass, oldRollClass];
	keptRoll = oldRoll;
	}

[stwlam]

I don't think we can do this until system version 8. To the extent the system has an API at all, this is part of it.

[7H3LaughingMan]

I mean, this works the same way as how it currently works with unevaluatedNewRoll and newRoll which can be modified at the moment since the object itself is being passed. Modules are already using these hooks to modify the new roll.

[CarlosFdez]

Any module listening to the hook would be receiving an object instead of a string now, so it would be a breaking change. I think this is a good idea but I agree that it should wait until system version 8 (which is when everything breaks anyways).