Fix Typings on DefinitelyTyped

[MeirionHughes]

• encoding-down
  • default export no longer available
• leveldown:
  • default export no longer available
  • getMany()
• rocksdb:
  • default export no longer available
  • getMany()
• levelup:
  • default export no longer available
  • getMany()

[sebastianst]

Cross-ref issue in levelup repo.

[sebastianst]

It would also be good to remove the unused type LevelUpBatch in the leveup types declaration file.

[MeirionHughes]

been delayed on this ... I'm in the middle of a init product release that is draining my will to live. Once that's done, and the rocksdb gets a new release, I'll start upgrading our dependencies and work through the types.

[sebastianst]

The return type of db.iterator() also needs to be fixed. It should be something like AsyncIterable<[K, V]>. The current custom return type doesn't allow for async (const x of it) syntax in typescript code.

[sebastianst]

The LevelUpConstructor interface could be improved to accept a ErrorValueCallback<LevelUp> as the third parameter, it currently only receives ErrorCallback. (Or ErrorValueCallback<LevelUp|undefined>?)

[vweevers]

Relevant: Level/abstract-level#5

[vweevers]

Closing because abstract-level and dependents have built-in type declarations. If someone wants to fix the typings of older modules on DT, go for it of course, but because @MeirionHughes is the main contributor of those types and seems to be busy, and the work needs to happen externally, I don't see an actionable item for us here.