bugfix: Ensure proper handling of empty metafile buffers

[Garefild]

Fix: Handle empty Uint8Array in parseJSON()

Backport → 0.27.4

Problem

When an optional JSON field was sent as an empty buffer, parseJSON() would decode the Uint8Array(0) into an empty string and pass it straight to JSON.parse("") — which unconditionally throws:

SyntaxError: Unexpected end of JSON input

Solution

parseJSON() now short-circuits on empty input, returning undefined before any decoding or parsing occurs. As a related change, parseJSON() is no longer called for an empty metafile buffer — result.metafile stays undefined when no metafile payload is present.

function parseJSON(bytes: Uint8Array): any {
  if (bytes.length === 0) return void 0; // absent, not malformed
  // ...
}

Fixes #4420.

[adamwong246]

downgrading to 0.27.3 worked for me

[Garefild]

downgrading to 0.27.3 worked for me

Yes, that does work, but I prefer to stay in sync with the latest releases.

From what I can tell, the issue is caused by the js api: fall back to js-based metafile json parser

The fix itself should be relatively straightforward. I’ve submitted a patch and am currently waiting for review.