1950211 - Add telemetry for calling well-known Symbol methods for RegExp on primitive values

Status: RESOLVED FIXED

(Core :: JavaScript: Standard Library, task, P3)

Description

[Dan Minor [:dminor]]

This normative change was approved at the February 2025 TC39 plenary. See https://github.com/tc39/ecma262/pull/3009.

Comment 1

[Nicolò Ribaudo]

Attachment: Bug 1950211 - Add telemetry for String methods calling RegExp symbols on primitives

This patch adds telemetry for https://github.com/tc39/ecma262/pull/3009.

That normative PR has already been approved by TC39, but we need to
verify that it's web compatible.

Comment 2

[Nicolò Ribaudo]

Attachment: Bug 1950211 - Do not use RegExp symbols on primitives in String methods

This patch implements (in nightly) the changes proposed in
https://github.com/tc39/ecma262/pull/3009, which got consensus at the
last TC39 meeting.

The new implementation still attempts to preserve telemetry, so that
we can keep collecting data about usage of this removed feature.
However, it cannot be 100% precise (see comments in the code).

This patch has test262 tests at https://github.com/tc39/test262/pull/4404,
but as far as I can tell they are too new and not included yet in
mozilla-central.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/6ea635bde2b6
Add telemetry for String methods calling RegExp symbols on primitives r=dminor,iain

Comment 4

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/6ea635bde2b6

Comment 5

[Nicolò Ribaudo]

Wait, this is not resolved yet. We only shipped telemetry for it.

Comment 6

[Nicolò Ribaudo]

Wait, this is not resolved yet. We only shipped telemetry for it. This will be fixed once D241314 is landed.

Comment 7

[Dan Minor [:dminor]]

To make this easier to keep track of, I'll make this bug just about the telemetry. I've filed https://bugzilla.mozilla.org/show_bug.cgi?id=1998177 for the normative change.

Comment 8

[Dan Minor [:dminor]]

Checking the telemetry, there are zero instances of people doing this, so I think we're ok to go ahead with the normative change.