Find APIs should possibly return undefined

[mswjs]

Find APIs should possibly return undefined

[kettanaito]

Hey, @camchenry. Thank you for yet another suggestion!

Would T | null work for your use case? It'd be great to align the returned value, and we do use null for update/delete operations already:

data/src/glossary.ts

Lines 136 to 140 in f8da857

	update(
	query: QuerySelector<Value<Dictionary[ModelName], Dictionary>> & {
	data: Partial<UpdateManyValue<Dictionary[ModelName], Dictionary>>
	},
	): EntityInstance<Dictionary, ModelName> | null

[marcosvega91]

I have noticed this some day ago and put it in the pr #67. Today i'll rebase the branch

[camchenry]

Yeah, T | null would work for me, and I'd imagine others as well. For pretty much all intents and purposes, I'd treat null and undefined interchangeably. For me, the main thing is being able to use the ??, and ?. operators to handle nullish values seamlessly, as well as doing a check like:

const entity = db.entity.findFirst(...);
if (!entity) {
  throw new Error(); // or return 404
}
// entity is now guaranteed to not be null/undefined

Thinking about it a little more though, this should probably only apply to the findFirst function, because it returns the entity directly rather than an array of entities. Because findFirst is analogous to Array.find and findMany is analogous to Array.filter?

[kettanaito]

Agree on that: let's retain findMany returning an empty array in the case when no entities matched the query. I find it a more pleasant data type to work with (both results.length and results.map are intuitive on empty results).

[kettanaito]

I believe with @67 merged findFirst and findMany now return the expected types:

data/src/glossary.ts

Lines 129 to 141 in 5cc1d73

	/**
	* Find a first entity matching the query.
	*/
	findFirst(
	query: QuerySelector<Value<Dictionary[ModelName], Dictionary>>,
	): Entity<Dictionary, ModelName> | null
	/**
	* Find multiple entities.
	*/
	findMany(
	query: WeakQuerySelector<Value<Dictionary[ModelName], Dictionary>> &
	BulkQueryOptions,
	): Entity<Dictionary, ModelName>[]