Repository navigation
javascript: new this.constructor() builds the receiver's class at each site - #1733
Merged
Merged
Conversation
swapnilpaliwal-sd
requested review from
JaredHLZhang,
Whua689 and
suyashpaliwal26
as code owners
September 29, 2026 00:55
…h site A method returning `new this.constructor(...)`, directly or through a const it initialises, was read as one merged value: every instantiated subclass of the declaring class, so each call on a clone fanned to all their overrides. Like a `this`-return, it is now substituted per site from the call's receiver. A `let` local and `new this()` in a static keep their merged value. Co-authored-by: axiomcode-bot[bot] <334110751+axiomcode-bot[bot]@users.noreply.github.com> Co-Authored-By: Claude <noreply@anthropic.com>
swapnilpaliwal-sd
force-pushed
the
loop/ja-is465
branch
from
September 29, 2026 00:56
4e3d343 to
a70d90e
Compare
Merged
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 join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
new this.constructor()in a method returned every instantiated subclass of the declaring class, so each call on a clone fanned to all their overrides. It is now substituted per site from the call's receiver, like athis-return (#464). This covers a direct return and aconstlocal that is filled in and then returned (the usual clone).new Base(), aletlocal, andnew this()in a static (the compiler types that one as the declaring class).Part of #465 (the
new this.constructor()item; #675 had reached a sound superset, this makes it exact).