297532 2025-08-18 07:30:19 -0700 [JSC] Fix `Iterator#flatMap` to handle iterators without `return` method 2025-08-20 10:42:13 -0700 1 1 1 Unclassified WebKit JavaScriptCore WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED InRadar P2 Normal --- 1 sosuke sosuke webkit-bug-importer oldest_to_newest 2137148 0 sosuke 2025-08-18 07:30:19 -0700 According to the spec, IteratorClose should check if the　return method exists before calling it, returning the completion value unchanged　when the method is undefined. However, the current implementation of Iterator.prototype.flatMap unconditionally calls iterated.return(), causing a TypeError when used with iterators that don't have a return method (e.g., Map.prototype.entries(), Set.prototype.values()). This patch fixes the issue by checking if the return method exists before calling it. original report https://github.com/oven-sh/bun/issues/17518 2137149 1 sosuke 2025-08-18 07:31:08 -0700 Pull request: https://github.com/WebKit/WebKit/pull/49530 2137755 2 ews-feeder 2025-08-20 10:41:37 -0700 Committed 298966@main (c4fa114ca0b7): <https://commits.webkit.org/298966@main> Reviewed commits have been landed. Closing PR #49530 and removing active labels. 2137756 3 webkit-bug-importer 2025-08-20 10:42:13 -0700 <rdar://problem/158783404>