Linus Groh

This got conditional stage 3 approval in today's TC39 meeting, including confirmation of the `groupBy` name.

Tests using `__proto__` without appropriate `features` entry

1

Found some randomly (there may be more, only did a quick search): https://github.com/tc39/test262/blob/e4f91b6381d7694265031caad0c71d733ac132f3/test/built-ins/TypedArrayConstructors/ctors/no-species.js#L29 https://github.com/tc39/test262/blob/e4f91b6381d7694265031caad0c71d733ac132f3/test/staging/ArrayBuffer/resizable/oobbehaves-like-detached.js#L25 https://github.com/tc39/test262/blob/e4f91b6381d7694265031caad0c71d733ac132f3/test/staging/ArrayBuffer/resizable/typed-array-prototype.js#L52 Unless `__proto__` is actually relevant to the test, `Object.get/setPrototypeOf()` should be preferred IMO. [`__proto__` is...

https://github.com/tc39/test262/blob/main/INTERPRETING.md only covers what should happen when it is being called with no arguments or an empty string and not what happens otherwise, as a result different engines/test262 harness implementations...

INTERPRETING.md should clarify that PASS/FAIL results are per test (file), not scenario (strict, non-strict)

2

The concept of a "test scenario" is not outlined in INTERPRETING.md but common in runners such as https://github.com/bocoup/test262-stream and https://github.com/bterlson/test262-harness, which reports separate PASS and FAIL results per test scenario...

Ports: zlib downloads HTML instead of an archive

3

``` [zlib/fetch] SHA256 checksum of downloaded file 'zlib-1.3.1.tar.gz' does not match! [zlib/fetch] Expected: db596507a0c7af737de0a096f0d43e025d3546d7c918e9bbfc860745d31c710b [zlib/fetch] Actual: 06baf57eb57bc30318923a86a746a873d3b2c50fddeb487df89ebd24d6d867e0 [zlib/fetch] Removed erroneous download. [zlib/fetch] Please run script again. ``` ``` $ wget...

Editorial: Return created EC from InitializeHostDefinedRealm

10

This AO is not being used in ECMA-262 directly, but from real-world experience implementing & using is as-is I can say that having to pull the Realm out of the...

> The phrase "the substring of S from inclusiveStart to exclusiveEnd" (where S is a String value or a sequence of code units and inclusiveStart and exclusiveEnd are integers) **denotes...

Synthesized constructor in ClassDefinitionEvaluation is missing [[PrivateMethods]] and [[Fields]]

1

These are only present in [ECMAScript Function Objects](https://tc39.es/ecma262/#sec-ecmascript-function-objects), however in the absence of a `constructor` method the function object is created as a [Built-in Function Object](https://tc39.es/ecma262/#sec-built-in-function-objects): > b. Let F...

This is no longer accurate: https://github.com/CanadaHonk/test262.fyi/blob/78cb8ddcf97cb42c3c40117d35bc6d484caf0437/site/index.html#L337-L338 https://github.com/CanadaHonk/test262.fyi/blob/78cb8ddcf97cb42c3c40117d35bc6d484caf0437/site/generate.mjs#L241 ESNext is now ES2025, i.e. edition 16: https://github.com/tc39/ecma262/commit/d502ea4acdde7e89a7e042dcc4e9123c6c75f476

I just found out that `Array.prototype.filter()` has ~230 tests (that's a low hanging fruit if I've ever seen one!) and thought it would be very useful to see at a...