webdriver: Support interspersed scroll actions via event queue by yezhizhen · Pull Request #43126 · servo/servo

yezhizhen · 2026-03-10T04:55:06Z

Scroll and PointerMove is quite similar. We did so for PointeMove in #42289 + #42946.

Imagine having 3 non-zero duration scroll actions with origin at different Elements.
Previously we would wait for one to be fully dispatched before moving to next action,
instead of interspersed.

We also consolidate PendingPointerMove and
newly added PendingScroll into enum PendingActions.

Testing:
Existing tests behaviour not changing.. Added a wdspec test.
Previously: ['wheel', 'wheel', 'wheel', 'wheel', 'wheel', 'wheel', 'wheel', 'wheel', 'wheel', 'move']
Now: ['wheel', 'move', 'wheel', 'move', 'wheel', 'move', 'move', 'wheel', 'wheel', 'move', 'move', 'wheel', 'wheel', 'move', 'move', 'wheel']

Signed-off-by: Euclid Ye <[email protected]>

yezhizhen

Pls just check the second commit. First commit removes the loop, and does fmt.

yezhizhen · 2026-03-10T04:59:59Z

components/webdriver_server/actions.rs

 }

-pub(crate) struct PendingPointerMove {
+#[expect(private_interfaces)]


This is to suppress

warning: type `PendingScroll` is more private than the item `PendingActions::Scroll::0` --> components\webdriver_server\actions.rs:69:12 | 69 | Scroll(PendingScroll), | ^^^^^^^^^^^^^ field `PendingActions::Scroll::0` is reachable at visibility `pub(crate)`

For our case, we just need PendingActions to be seen in lib.rs to declare Vec<PendingActions>.

yezhizhen · 2026-03-10T05:00:21Z

components/webdriver_server/lib.rs

-    pending_pointer_moves: Vec<PendingPointerMove>,
+    /// Ongoing [`PointerMoveAction`] or [`WheelScrollAction`] that are being incrementally
+    /// processed across multiple execution cycles within the current tick.
+    pending_actions: Vec<PendingActions>,


servo-wpt-sync · 2026-03-10T09:17:38Z

🤖 Opened new upstream WPT pull request (web-platform-tests/wpt#58388) with upstreamable changes.

github-actions · 2026-03-10T09:18:33Z

🔨 Triggering try run (#22895449385) for Linux (WPT)

servo-wpt-sync · 2026-03-10T09:18:51Z

✍ Updated existing upstream WPT pull request (web-platform-tests/wpt#58388) title and body.

servo-wpt-sync · 2026-03-10T09:24:31Z

✍ Updated existing upstream WPT pull request (web-platform-tests/wpt#58388) title and body.

github-actions · 2026-03-10T09:30:39Z

Test results for linux-wpt from try job (#22895449385):

Flaky unexpected result (1)

OK /webdriver/tests/classic/get_alert_text/get.py
- FAIL [expected PASS] subtest: test_get_confirm_text
```
AssertionError: no such alert (404): No user prompt is currently active.
```

github-actions · 2026-03-10T09:30:47Z

✨ Try run (#22895449385) succeeded.

servo-wpt-sync · 2026-03-10T09:46:03Z

📝 Transplanted new upstreamable changes to existing upstream WPT pull request (web-platform-tests/wpt#58388).

servo-wpt-sync · 2026-03-10T10:26:04Z

✍ Updated existing upstream WPT pull request (web-platform-tests/wpt#58388) title and body.

servo-wpt-sync · 2026-03-10T10:32:19Z

📝 Transplanted new upstreamable changes to existing upstream WPT pull request (web-platform-tests/wpt#58388).

servo-wpt-sync · 2026-03-10T11:22:37Z

📝 Transplanted new upstreamable changes to existing upstream WPT pull request (web-platform-tests/wpt#58388).

servo-wpt-sync · 2026-03-10T11:31:41Z

✍ Updated existing upstream WPT pull request (web-platform-tests/wpt#58388) title and body.

Signed-off-by: Euclid Ye <[email protected]>

servo-wpt-sync · 2026-03-10T11:59:47Z

📝 Transplanted new upstreamable changes to existing upstream WPT pull request (web-platform-tests/wpt#58388).

servo-wpt-sync · 2026-03-10T12:01:52Z

✍ Updated existing upstream WPT pull request (web-platform-tests/wpt#58388) title and body.

github-actions · 2026-03-10T12:48:03Z

🔨 Triggering try run (#22903188798) for Linux (WPT)

github-actions · 2026-03-10T13:00:50Z

Test results for linux-wpt from try job (#22903188798):

Flaky unexpected result (1)

OK /webdriver/tests/classic/get_alert_text/get.py
- FAIL [expected PASS] subtest: test_get_confirm_text
```
AssertionError: no such alert (404): No user prompt is currently active.
```

Stable unexpected results (1)

TIMEOUT [expected OK] /webdriver/tests/classic/perform_actions/perform.py

github-actions · 2026-03-10T13:00:59Z

⚠️ Try run (#22903188798) failed!

yezhizhen · 2026-03-10T13:41:35Z

New test is intermittent for Servo. Seems to be a bug in script.
Fixing in another PR.

yezhizhen · 2026-03-10T13:53:59Z

Filed #43136

…vent` when coalescing wheel events (#43138) Basically, any testdriver tests with scroll duration more than `16ms` can be intermittent due to this. Fixes: #43136 Fixes: #43110 Testing: This fixes the issue where newly added test in #43126 randomly TIMEOUT with very high probability: https://github.com/servo/servo/actions/runs/22906496902 Signed-off-by: Euclid Ye <[email protected]>

xiaochengh

Makes sense, LGTM.

yezhizhen added 2 commits March 10, 2026 11:57

Remove loop and fmt

a44f2bb

Signed-off-by: Euclid Ye <[email protected]>

event loop

6329e43

Signed-off-by: Euclid Ye <[email protected]>

yezhizhen requested a review from xiaochengh March 10, 2026 04:55

servo-highfive added the S-awaiting-review There is new code that needs to be reviewed. label Mar 10, 2026

yezhizhen commented Mar 10, 2026

View reviewed changes

servo-wpt-sync mentioned this pull request Mar 10, 2026

webdriver: Support interspersed scroll actions via event queue web-platform-tests/wpt#58388

Merged

yezhizhen added the T-webdriver Do a try run of the WebDriver conformance tests label Mar 10, 2026

github-actions bot removed the T-webdriver Do a try run of the WebDriver conformance tests label Mar 10, 2026

yezhizhen force-pushed the interspersed-scroll branch from b3b4e97 to b6c5db3 Compare March 10, 2026 09:42

yezhizhen force-pushed the interspersed-scroll branch from b6c5db3 to c8a7267 Compare March 10, 2026 10:28

yezhizhen force-pushed the interspersed-scroll branch 2 times, most recently from c230ee1 to 97c7a8c Compare March 10, 2026 11:18

Add wdspec interspersed wheel/pointermove event test

7c724b1

Signed-off-by: Euclid Ye <[email protected]>

yezhizhen force-pushed the interspersed-scroll branch from 97c7a8c to 7c724b1 Compare March 10, 2026 11:56

yezhizhen added the T-webdriver Do a try run of the WebDriver conformance tests label Mar 10, 2026

github-actions bot removed the T-webdriver Do a try run of the WebDriver conformance tests label Mar 10, 2026

yezhizhen mentioned this pull request Mar 10, 2026

script: Replace the InputEventId of existing_constellation_wheel_event when coalescing wheel events #43138

Merged

xiaochengh approved these changes Mar 11, 2026

View reviewed changes

servo-highfive removed the S-awaiting-review There is new code that needs to be reviewed. label Mar 11, 2026

yezhizhen added this pull request to the merge queue Mar 11, 2026

servo-highfive added the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Mar 11, 2026

Merged via the queue into servo:main with commit 605291b Mar 11, 2026
48 of 50 checks passed

yezhizhen deleted the interspersed-scroll branch March 11, 2026 04:17

servo-highfive removed the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Mar 11, 2026

Uh oh!

Conversation

yezhizhen commented Mar 10, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

yezhizhen left a comment

Choose a reason for hiding this comment

Uh oh!

yezhizhen Mar 10, 2026

Choose a reason for hiding this comment

Uh oh!

yezhizhen Mar 10, 2026

Choose a reason for hiding this comment

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

github-actions bot commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

github-actions bot commented Mar 10, 2026

Uh oh!

github-actions bot commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

servo-wpt-sync commented Mar 10, 2026

Uh oh!

github-actions bot commented Mar 10, 2026

Uh oh!

github-actions bot commented Mar 10, 2026

Uh oh!

github-actions bot commented Mar 10, 2026

Uh oh!

yezhizhen commented Mar 10, 2026

Uh oh!

yezhizhen commented Mar 10, 2026

Uh oh!

xiaochengh left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

yezhizhen commented Mar 10, 2026 •

edited

Loading