304996 2026-01-06 11:30:40 -0800 WebTransportError constructor mishandles single options argument and treats it as message 2026-01-08 13:21:24 -0800 1 1 1 Unclassified WebKit New Bugs WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED InRadar P2 Normal --- 1 ankshit_jain achristensen achristensen webkit-bug-importer oldest_to_newest 2169673 0 ankshit_jain 2026-01-06 11:30:40 -0800 When WebTransportError is constructed with a single options object argument, the object is incorrectly interpreted as the message parameter and stringified to "[object Object]", rather than being recognized as the options dictionary. ``` // Fail const e1 = new WebTransportError({ streamErrorCode: 42 }); console.log(e1.streamErrorCode); // null (expected: 42) console.log(e1.message); // "[object Object]" (expected: "") // Pass const e2 = new WebTransportError('test error', { streamErrorCode: 42 }); console.log(e2.streamErrorCode); // 42 (expected: 42) console.log(e2.message); // "test error" (expected: "test error") ``` The IDL interface correctly marks both arguments as optional: ``` interface WebTransportError : DOMException { constructor(optional DOMString message = "", optional WebTransportErrorOptions options = {}); readonly attribute WebTransportErrorSource source; readonly attribute unsigned long? streamErrorCode; }; ``` 2169685 1 achristensen 2026-01-06 12:18:08 -0800 This seems to be an issue with the generated JSWebTransportErrorDOMConstructor::construct. I'm not sure if we have other functions with multiple optional arguments of different types, but it should try to line up the types. 2169889 2 webkit-bug-importer 2026-01-06 17:44:02 -0800 <rdar://problem/167662230> 2169893 3 achristensen 2026-01-06 17:46:20 -0800 Pull request: https://github.com/WebKit/WebKit/pull/56176 2170401 4 ews-feeder 2026-01-08 13:21:22 -0800 Committed 305306@main (d6cbf74934a6): <https://commits.webkit.org/305306@main> Reviewed commits have been landed. Closing PR #56176 and removing active labels.