feat: migrate ThreadList to PaginatedVirtualList by srijnabhargav · Pull Request #40845 · RocketChat/Rocket.Chat

srijnabhargav · 2026-06-08T13:27:29Z

Proposed changes

This PR migrates ThreadList from react-virtuoso to the shared PaginatedVirtualList component introduced by the Virtua foundation work.

Changes include:

Replacing the existing react-virtuoso implementation with PaginatedVirtualList
Aligning ThreadList with the same consumer pattern used in DiscussionsList
Removing Virtuoso-specific setup and resize handling
Reusing the shared virtualization infrastructure to reduce duplication and simplify future maintenance

The goal is to keep ThreadList consistent with the new virtualization approach while keeping the scope of the PR limited to ThreadList-specific changes.

Issue(s)

Part of the Virtua migration work for the contextual bar lists.

Further comments

This PR should be merged after the Virtua foundation work (PaginatedVirtualList and DiscussionsList migration), #39394 as it reuses the shared virtualization infrastructure introduced there and only contains ThreadList-specific changes.

Summary by CodeRabbit

Refactor
- Improved thread list rendering by simplifying the virtualization approach and implementing pagination instead.
- Enhanced pagination behavior to prevent unnecessary data fetching while loading.
Tests
- Updated thread list test setup.

dionisio-bot · 2026-06-08T13:27:34Z

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changeset-bot · 2026-06-08T13:27:36Z

⚠️ No Changeset found

Latest commit: f0c1e62

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coderabbitai · 2026-06-08T13:27:54Z

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: b2289a94-46ba-49e3-8a43-3a164c3d9752

📥 Commits

Reviewing files that changed from the base of the PR and between 6908462 and f0a93f0.

📒 Files selected for processing (2)

apps/meteor/client/views/room/contextualBar/Threads/ThreadList.spec.tsx
apps/meteor/client/views/room/contextualBar/Threads/ThreadList.tsx

💤 Files with no reviewable changes (1)

apps/meteor/client/views/room/contextualBar/Threads/ThreadList.spec.tsx

🚧 Files skipped from review as they are similar to previous changes (1)

apps/meteor/client/views/room/contextualBar/Threads/ThreadList.tsx

📜 Recent review details

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

GitHub Check: cubic · AI code reviewer

Walkthrough

ThreadList component is migrated from react-virtuoso to PaginatedVirtualList. The change removes useResizeObserver-based container sizing and updates test mocks accordingly. Pagination behavior is refined to disable onEndReached while pending.

Changes

ThreadList Migration to PaginatedVirtualList

Layer / File(s)	Summary
ThreadList component virtualization migration `apps/meteor/client/views/room/contextualBar/Threads/ThreadList.tsx`	`ThreadList` replaces react-virtuoso with `PaginatedVirtualList`, removes `useResizeObserver` hook and its ref-based sizing measurement, wraps the list in a `Box` with `minHeight: 0`, and conditionally disables `onEndReached` callback while pending. Imports are updated to reflect the new virtualization dependency.
ThreadList test infrastructure cleanup `apps/meteor/client/views/room/contextualBar/Threads/ThreadList.spec.tsx`	`VirtuosoMockContext` import and its `Provider` wrapper are removed from the "error-not-allowed" test case; the HTTP endpoint mock and rendered error assertion remain unchanged.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Suggested reviewers

MartinSchoeler

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: migrating ThreadList component from react-virtuoso to PaginatedVirtualList, which is the primary focus of the changeset.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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cubic-dev-ai

1 issue found across 14 files

Prompt for AI agents (unresolved issues)


Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="apps/meteor/client/components/VirtualList/VirtualList.tsx">

<violation number="1" location="apps/meteor/client/components/VirtualList/VirtualList.tsx:67">
P1: Pagination lock can get permanently stuck after a successful `onEndReached` call that does not change tracked item metadata, blocking all future pagination.</violation>
</file>

_{Reply with feedback, questions, or to request a fix.

Re-trigger cubic}

cubic-dev-ai · 2026-06-08T13:36:33Z

+			if (isEndReachedLockedRef.current) {
+				return;
+			}
+			isEndReachedLockedRef.current = true;


P1: Pagination lock can get permanently stuck after a successful onEndReached call that does not change tracked item metadata, blocking all future pagination.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At apps/meteor/client/components/VirtualList/VirtualList.tsx, line 67: <comment>Pagination lock can get permanently stuck after a successful `onEndReached` call that does not change tracked item metadata, blocking all future pagination.</comment> <file context> @@ -0,0 +1,109 @@ + if (isEndReachedLockedRef.current) { + return; + } + isEndReachedLockedRef.current = true; + + try { </file context>

cubic-dev-ai

No issues found across 2 files

_{Re-trigger cubic}

codecov · 2026-06-11T13:49:26Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 70.07%. Comparing base (1a9ced9) to head (f0c1e62).
⚠️ Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #40845      +/-   ##
===========================================
+ Coverage    70.02%   70.07%   +0.04%     
===========================================
  Files         3355     3355              
  Lines       129162   129153       -9     
  Branches     22337    22392      +55     
===========================================
+ Hits         90443    90500      +57     
+ Misses       35421    35356      -65     
+ Partials      3298     3297       -1

Flag	Coverage Δ
e2e	`59.24% <ø> (-0.02%)`	⬇️
e2e-api	`46.26% <ø> (+0.07%)`	⬆️
unit	`69.98% <100.00%> (+0.05%)`	⬆️

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srijnabhargav · 2026-06-11T15:23:15Z

Rebased onto the latest develop after the Virtua foundation PR merged. No functional changes beyond the ThreadList migration.

srijnabhargav requested a review from a team as a code owner June 8, 2026 13:27

dionisio-bot Bot added the community label Jun 8, 2026

srijnabhargav marked this pull request as draft June 8, 2026 13:27

coderabbitai Bot added the type: feature Pull requests that introduces new feature label Jun 8, 2026

cubic-dev-ai Bot reviewed Jun 8, 2026

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srijnabhargav force-pushed the feat/virtua-threadlist-migration branch from 6908462 to 019d3de Compare June 8, 2026 17:58

srijnabhargav marked this pull request as ready for review June 8, 2026 17:59

cubic-dev-ai Bot reviewed Jun 8, 2026

View reviewed changes

srijnabhargav force-pushed the feat/virtua-threadlist-migration branch from 019d3de to e21d902 Compare June 8, 2026 18:39

coderabbitai Bot removed the type: feature Pull requests that introduces new feature label Jun 8, 2026

srijnabhargav added 2 commits June 11, 2026 20:45

feat: migrate ThreadList to PaginatedVirtualList

194cb26

fix: order ThreadList imports

f0c1e62

srijnabhargav force-pushed the feat/virtua-threadlist-migration branch from f0a93f0 to f0c1e62 Compare June 11, 2026 15:17

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