Improve apparent type of mapped types with mapped type modifiers#58091
Closed
Andarist wants to merge 1 commit intomicrosoft:mainfrom
Closed
Improve apparent type of mapped types with mapped type modifiers#58091Andarist wants to merge 1 commit intomicrosoft:mainfrom
Andarist wants to merge 1 commit intomicrosoft:mainfrom
Conversation
typescript-bot
added
the
For Uncommitted Bug
Andarist
commented
Apr 5, 2024
| if (constraint.flags & TypeFlags.Index) { | ||
| const baseConstraint = getBaseConstraintOfType((constraint as IndexType).type); | ||
| if (baseConstraint && everyType(baseConstraint, t => isArrayOrTupleType(t) || isArrayOrTupleOrIntersection(t))) { | ||
| return instantiateType(target, prependTypeMapping(typeVariable, baseConstraint, type.mapper)); |
Contributor
Author
There was a problem hiding this comment.
The type.mapper here looks something like:
m1: T_id -> Box<string>[]
m2: m1: K -> K
m2: m1: T_id -> UnboxArray<T_outer>
m2: T_id -> UnboxArray<T_outer>Since typeVariable is T_id TS ended up "skipping" over the inner mapping of UnboxArray. The constraint (of the type) is keyof T_outer with a baseConstraint of Box<string>[].
In a sense, I'd like to map T_outer to baseConstraint (Box<string>[]), process that through type.mapper and then map T_id to that result (or smth along those lines). I couldn't find a clear way to do that given that we need to account for non-homomorphic instantiations of homomorphic mapped types here. Using the modifiers type does seem to do the trick but I'm not overly confident in this solution and I won't mind being proven that this is wrong 😉
Member
|
@typescript-bot test it |
Collaborator
Collaborator
|
Hey @jakebailey, the results of running the DT tests are ready. Everything looks the same! |
Collaborator
|
@jakebailey Here are the results of running the user tests comparing Everything looks good! |
Collaborator
|
@jakebailey Here they are:
tscComparison Report - baseline..pr
System info unknown
Hosts
Scenarios
Developer Information: |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Collaborator
|
@jakebailey Here are the results of running the top 400 repos comparing Everything looks good! |
Member
Contributor
Author
|
Damn, I was close! :P It was worth a shot :) |
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
4 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
fixes #58060