deeplyFulfilled erases type information

[turadg]

https://github.com/endojs/endo/blob/master/packages/marshal/src/deeplyFulfilled.js#L36-L39

https://github.com/endojs/endo/blob/master/packages/marshal/src/types.js#L26

Because Passable is any, the type passed into deeplyFulfilled gets erased. The decision to adopt bare deeplyFulfilled in Agoric/agoric-sdk@a8db354 has erased type information there. Example impact: I just had a CI failure from a refactoring that the types would have alerted me to.

[dckc]

This week I sort of got bit by this.

The type-safe alternative, deeplyFulfilledObject, didn't work out either, though:

https://github.com/Agoric/agoric-sdk/pull/6774/commits/eb26cb200f2c68d8a636380c871090fe4468f67fb3

part of:

• fix(smart-wallet): create purses for new assets lazily Agoric/agoric-sdk#6774

[erights]

Not directly relevant, but worth linking to: Agoric/agoric-sdk#6816

[turadg]

May be solved by bringing these types over from sdk, https://github.com/Agoric/agoric-sdk/blob/master/packages/internal/src/utils.js#L160-L168

[erights]

Would #1933 address this issue?

[turadg]

Would #1933 address this issue?

No, because the return type still widens to Passable. We need the function to be generic on its parameters.