Expose full $262 object in boa_cli

[ivankra]

ECMASCript feature

I'm interested in running test262 on boa eshost-style - using boa_cli shell rather than the separate integrated tester binary (boa_tester). This requires $262 object, which boa_cli doesn't directly expose - there's $boa (with --debug-object) but 1) it requires maintaining a custom shim to map $boa <-> $262 methods which is error- and labor-prone (especially for complex logic like $262.agent) and 2) doesn't provide some methods, like detachArrayBuffer and now the recently added IsHTMLDDA, so there are discrepancies in test results.

Could you the expose the full internal $262 object (js262.rs) in boa_cli? I suppose --debug-object flag can be reused to add both $boa and $262.

[spec]: https://github.com/tc39/test262/blob/main/INTERPRETING.md#host-defined-functions

Example code

Properties like $262.detachArrayBuffer, $262.agent, $262.IsHTMLDDA should be available with boa --debug-object (or another flag)

[jedel1043]

I think we can do that and add a flag for it. IMO a good place for it would be boa_runtime so that we can share the same code between boa_cli and boa_tester

[linisha15]

Thanks for the explanation! I also find this idea interesting and would be happy to help work on it. My understanding is that the $262 object could be exposed through a flag in boa_cli, with the implementation placed in boa_runtime so that both boa_cli and boa_tester can reuse the same logic. Please let me know if that approach sounds correct.

[ivankra]

I slapped together a refactoring with claude/codex, both arriving at a roughly similar change: 59f449e

And a few other minor things to help make boa cli usable for test262: #5234