Add TextDecoder fallback when fatal is unsupported

[JoelTowell]

Summary

TextStreamReader currently constructs TextDecoder('utf-8', { fatal: true }) unconditionally. I ran into an issue with React Native where TextDecoder is present, but constructing it with fatal: true throws:

Failed to construct 'TextDecoder': the 'fatal' option is unsupported

As a result, text stream handling fails before any decoding happens. This may not be isolated to one environment, as Expo explicitly notes that "[t]he TextDecoder API is not spec-compliant on native platforms".

The LiveKit React Native SDK uses a polyfill for TextDecoder (1, 2), but this will only take effect if TextDecoder is not already defined.

Based on discussion, change has been simplified from fallback to omitting the offending option.

Changes

• Stop passing fatal: true when constructing TextDecoder in TextStreamReaderand bytesToDecodedUtf8 function

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🦋 Changeset detected

Latest commit: a48e60c

The changes in this PR will be included in the next version bump.

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Name	Type
livekit-client	Patch

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[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no potential bugs to report.

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[xianshijing-lk]

it looks good to me, and will get @1egoman or @lukasIO to take a final look

[JoelTowell]

it looks good to me, and will get @1egoman or @lukasIO to take a final look

Thanks @xianshijing-lk ! I addressed the comment by Devin before I saw your comment. Happy to revert those changes if they are unwanted, though they make sense to me.

[1egoman]

@JoelTowell Good catch here! I think this can be even simpler - you probably can just remove fatal: true outright rather than add all the additional switching logic. In practice, the bytes of a text data stream should always be valid utf-8 (according to the protocol) and adding all the switching logic introduces a lot of extra complexity.

[devin-ai-integration]

Devin Review found 1 new potential issue.

View 3 additional findings in Devin Review.

[JoelTowell]

@JoelTowell Good catch here! I think this can be even simpler - you probably can just remove fatal: true outright rather than add all the additional switching logic. In practice, the bytes of a text data stream should always be valid utf-8 (according to the protocol) and adding all the switching logic introduces a lot of extra complexity.

Thanks @1egoman! I reverted my changes and just stopped passing fatal: true to the constructor. I updated the PR description as well. Devin doesn't seem thrilled about it, but I'm certain you're a better judge. Should be good to merge. 🙂

[1egoman]

Yep I think it should be fine in practice. Thanks for the contribution!