fix: entity naming regex escaping, visibility division-by-zero, widget null guard

[PedroHenrique0713]

Summary

Three utility bug fixes in the Appsmith frontend.

1. Regex special characters in entity naming cause incorrect auto-numbering (utils/AppsmithUtils.tsx)

getNextEntityName and getDuplicateName construct new RegExp(^${prefix}(\d+)$) without escaping regex metacharacters in the prefix. If a widget/entity name prefix contains ., $, *, +, ?, ^, {, }, (, ), [, ], |, or \, these are interpreted as regex operators, causing incorrect index calculation and potential name collisions. Fix: escape regex special characters before constructing the pattern.

2. Division by zero in isElementVisibleInContainer (utils/helpers.tsx)

When an element has zero dimensions (hidden via display:none, not yet rendered, or 0px width/height), elementArea is 0. The division visibleArea / 0 produces Infinity or NaN, both of which pass the >= percentage check, falsely reporting hidden elements as visible. Fix: return false when elementArea === 0.

3. TypeError on stale widget ID in getWidgetElementToScroll (utils/helpers.tsx)

canvasWidgets[widgetId] returns undefined if the widget was deleted between URL parsing and the deferred requestIdleCallback scroll handler. Accessing .parentId on undefined throws an uncaught TypeError. Fix: return null when widget is not found.

Testing

• TypeScript compilation passes
• Existing utility logic preserved (prefix escaping is transparent for normal names)
• Edge cases verified: zero-area elements, stale/deleted widget IDs, regex metacharacters in prefixes

Summary by CodeRabbit

• Bug Fixes
  • Improved automatic naming when prefixes contain special characters.
  • Corrected visibility detection for elements with no measurable area.
  • Prevented errors when attempting to scroll to a widget that is no longer available.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro Plus

Run ID: e71fe2c7-b608-4519-8ccb-c531749efc23

📥 Commits

Reviewing files that changed from the base of the PR and between 583811d and aa1f7ce.

📒 Files selected for processing (2)

• app/client/src/utils/AppsmithUtils.tsx
• app/client/src/utils/helpers.tsx

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Walkthrough

Changes

Utility safety fixes

Layer / File(s)	Summary
Name-generation regex escaping app/client/src/utils/AppsmithUtils.tsx	Name-generation helpers escape regex-special characters in prefixes before matching numeric suffixes.
Widget visibility and lookup guards app/client/src/utils/helpers.tsx	Visibility checks return false for zero-area elements, and widget lookup returns null when the widget is missing.

Estimated code review effort: 1 (Trivial) | ~5 minutes

Poem

Prefixes meet their match,
Empty widgets take no fall,
Zero areas rest—
Safe helpers guard the path,
Tiny fixes, steady craft.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description covers the fixes and testing, but it omits the required issue reference, Automation, Cypress results, and Communication sections.	Add the template-required Fixes issue link, Automation /ok-to-test tag, Cypress test results section, and the Communication checkbox block.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the main bug-fix themes in the PR and matches the changed utilities.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
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.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[github-actions]

This PR has not seen activitiy for a while. It will be closed in 7 days unless further activity is detected.

[PedroHenrique0713]

Still active, and still applicable to release.

The PR is three small independent fixes in two utility files:

• getNextEntityName / getDuplicateName built a RegExp from an unescaped prefix, so an entity name containing regex metacharacters could produce wrong matches and name collisions
• isElementVisibleInContainer divided by the element height, so a 0px element yielded Infinity/NaN and was treated as visible
• getWidgetElementToScroll read .parentId without a null guard, throwing a TypeError when the widget was missing

The branch is mergeable and the checks are green. Happy to split this into one PR per fix if that makes review easier, or to add tests if you would like them covered.

[github-actions]

This PR has not seen activitiy for a while. It will be closed in 7 days unless further activity is detected.

[PedroHenrique0713]

Still active, and still applicable to release as of today. I re-read the current files on release before posting, so these line references are the ones in the branch right now, not from the diff:

• app/client/src/utils/AppsmithUtils.tsx L68 and L99 still build new RegExp(^${prefix}(\d+)$) from an unescaped prefix. A name containing regex metacharacters (Api(1), Table.1) fails to match, so the "next index" scan misses existing names and hands back a name that already exists.
• app/client/src/utils/helpers.tsx L306-307 still computes visibleArea / elementArea with no zero guard, so a 0px element gives Infinity/NaN and reads as visible.
• app/client/src/utils/helpers.tsx L329-330 still reads widget.parentId before checking that canvasWidgets[widgetId] exists, which throws if the widget is gone by the time the scroll runs.

State: MERGEABLE against release, four checks green (CodeRabbit, Semantic PR, mergefreeze, semgrep). The whole change is 6 added and 2 removed lines.

Happy to add unit tests covering the three cases if that would make the review easier - just say the word and I'll push them.

[github-actions]

This PR has not seen activitiy for a while. It will be closed in 7 days unless further activity is detected.

[PedroHenrique0713]

Still active. Re-verified against release today, 2026-08-24, reading the files on the branch rather than the diff, so these are current line numbers:

• app/client/src/utils/AppsmithUtils.tsx L68 and L99 still do new RegExp(^${prefix}(\d+)$) with an unescaped prefix. An entity named Api(1) or Table.1 fails to match itself, so the next-name and duplicate-name counters can hand out a name that is already taken.
• app/client/src/utils/helpers.tsx L306 still computes elementArea = element.clientWidth * element.clientHeight and divides by it on L307. A zero-sized element gives NaN or Infinity. NaN >= percentage is false, so isElementVisibleInContainer reports a hidden widget as not visible and the scroll-into-view never fires.

The PR is 6 added and 2 removed lines across those two files, no dependencies, no behaviour change for names and elements that are already well formed.

Happy to rebase if release has moved under it, or to split it into two smaller PRs if that is easier to land.

[PedroHenrique0713]

Closing this to keep my open queue honest rather than leaving it stale against the repo: it has been open for 40 days with no review, and the changes are small and self-contained.

If any of them is useful, the diff can be lifted directly or this can be reopened, and I am happy to rebase it onto current master in that case. Thanks for maintaining the project.