Meta: implement TransferArrayBuffer correctly in reference implementation
#1353
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MattiasBuelens
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Aug 15, 2025
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| const byteOffset = view.byteOffset; | ||
| const byteLength = view.byteLength; |
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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; | ||
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| return transferredIshVersion; | ||
| return ArrayBufferPrototypeTransferToFixedLength.call(O); |
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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. 😉
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domenic
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Aug 19, 2025
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Nice! I guess you might want to roll in web-platform-tests/wpt#54350 before merging?
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Done, ready to land. 🛬 |
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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.)
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