1644160 - Proxy Support for Private Fields

Status: RESOLVED FIXED

(Core :: JavaScript Engine, task, P2)

Description

[Matthew Gaudet (he/him) [:mgaudet]]

Private fields have some complicated (for the engine to implement) semantics.

Comment 1

[Matthew Gaudet (he/him) [:mgaudet]]

The implementation I have with my current patches adds a hidden expando to proxies to support adding private fields to them

In the Chome(/Edge Beta) devtools, when you stamp a private field onto a proxy, you can inspect it. I think we'll need to open a bug later to do the same thing.

Comment 2

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1644160 - Initial Proxy Support for Private Fields r?jorendorff

Comment 3

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1644160 - Support private fields that traverse CCWs r?jorendorff

Depends on D83145

Comment 4

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1644160 - Support DeadObjectProxies r?jorendorff

Depends on D83146

Comment 5

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1644160 - Ensure TypedObjects cannot have private fields added r?jorendorff

Depends on D83147

Comment 6

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1644160 - Add test cases for various DOM related classes r?jorendorff!

• CrossOriginWrappers
• A variety DOM objects (including window, and window's prototype chain)
• Xray wrappers

I am seeking advice with this for pointers on how to test other proxy types
I think am aware of:

• Cross Process Object Wrappers

as well as those I am not aware of.

Depends on D83511

Comment 7

[Matthew Gaudet (he/him) [:mgaudet]]

Attachment: Bug 1644160 - Use DOM Proxy Expando to hold private fields, rather than allocating Proxy Expando r?jorendorff

Depends on D83555

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/598d65b8afb5
Initial Proxy Support for Private Fields r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/3c88625982cf
Support private fields that traverse CCWs r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/09df89442319
Support DeadObjectProxies r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/bc43898badcd
Ensure TypedObjects cannot have private fields added r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/ce53b1934083
Use DOM Proxy Expando to hold private fields, rather than allocating Proxy Expando r=jorendorff

Comment 9

[Atila Butkovits]

Backed out for failure at proxy-ccw.js

Backout link: https://hg.mozilla.org/integration/autoland/rev/b1d2d66897f8480dda540ff2507f836c24b5fd42

Push with failures :https://treeherder.mozilla.org/#/jobs?repo=autoland&resultStatus=testfailed%2Cbusted%2Cexception&revision=ce53b19340838499ea919ee498bf36bd0af97f30&searchStr=j1&selectedTaskRun=EL-SMpLcSfuZmvoeMl_Low.0

Failure log: https://treeherder.mozilla.org/logviewer.html#/jobs?job_id=310379859&repo=autoland&lineNumber=7539

Comment 10

[Matthew Gaudet (he/him) [:mgaudet]]

So, Tom did mention on IRC that it's not -amazing- that we're increasing the number of slots on DOM proxies; I tend to agree, but don't think it's worth blocking landing this. AWSY results are fairly inconclusive.

Comment 11

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/49b15ed562b9
Initial Proxy Support for Private Fields r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/b5648f412d71
Support private fields that traverse CCWs r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/1feadd426f1d
Support DeadObjectProxies r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/a8ee2ca60605
Ensure TypedObjects cannot have private fields added r=jorendorff
https://hg.mozilla.org/integration/autoland/rev/ab9768a4a9f3
Use DOM Proxy Expando to hold private fields, rather than allocating Proxy Expando r=jorendorff

Comment 12

[Bogdan Tara[:bogdan_tara | bogdant]]

https://hg.mozilla.org/mozilla-central/rev/49b15ed562b9
https://hg.mozilla.org/mozilla-central/rev/b5648f412d71
https://hg.mozilla.org/mozilla-central/rev/1feadd426f1d
https://hg.mozilla.org/mozilla-central/rev/a8ee2ca60605
https://hg.mozilla.org/mozilla-central/rev/ab9768a4a9f3

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/9f4aef254bea
Add test cases for various DOM related classes r=jorendorff

Comment 14

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/9f4aef254bea