Meta: implement TransferArrayBuffer correctly in reference implementation
#1353
Conversation
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
MattiasBuelens
commented
Aug 15, 2025
Comment on lines
+1587
to
+1588
| const byteOffset = view.byteOffset; | ||
| const byteLength = view.byteLength; |
There was a problem hiding this comment.
The reference implementation was doing steps 8 and 9 after calling TransferArrayBuffer, which meant that view.byteLength was already 0. We didn't notice this, because we weren't actually transferring before. 😛
Fortunately, all "real" implementations already do this correctly.
| O[isFakeDetached] = true; | ||
|
|
||
| return transferredIshVersion; | ||
| return ArrayBufferPrototypeTransferToFixedLength.call(O); |
There was a problem hiding this comment.
I'm using transferToFixedLength() since we don't (yet) support resizable ArrayBuffers.
I think we can loosen that restriction, but we should do that in an actual spec change. 😉
MattiasBuelens
force-pushed
the
ref-impl-arraybuffer-transfer
branch
from
852ded4 to
5cde2af
Compare
domenic
approved these changes
Aug 19, 2025
There was a problem hiding this comment.
Nice! I guess you might want to roll in web-platform-tests/wpt#54350 before merging?
|
Done, ready to land. 🛬 |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 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Outdated suggestions cannot be applied.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.
Previously, the reference implementation did not implement the
TransferArrayBufferabstract op correctly, because we didn't have a way of doing that synchronously in user-land code. Today, we can useArrayBuffer.prototype.transfer()for that.At least two implementers are interested (and none opposed)ArrayBuffer.transfer()in Streams tests web-platform-tests/wpt#54350Implementation bugs are filedMDN issue is filed(See WHATWG Working Mode: Changes for more details.)
Preview | Diff