Fixes issue #94521: Make sure to always specify Uint32Array length #94529
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This PR fixes #94521 for the 1.44 release.
When the
decodeSemanticTokensDtowas called, it was possible that it was called with aVSBufferthat uses aUint8Arraywhich is misaligned on a backingArrayBuffer. Think about a large data blob (a message from the ext host) and only a portion of it is the encoded semantic tokens dto.The code handled the misaligned case before (see the check
uint8Arr.byteOffset % 4 === 0), but the handling was incomplete because a length was not passed to the Uint32Array ctor. When the length is not passed in, the Uint32Array will try to use theArrayBuffer.byteLength / 4, but that might be beyond the length of the passed inVSBufferinto memory of the backingArrayBuffer, which might not be a multiple of 4.The unit tests show this case clearly, but unfortunately there are no steps given this has to do with the way in which the extension host can end up serializing a batch of messages into a single blob...