FILES field - Attachment name display fix

[etiennejouan]

with new 'file' FILES field on attachment, UI should display attachment name from file field value.
Issue with API users updating only 'file' FILES field (and not name field anymore)

[cubic-dev-ai]

No issues found across 1 file

[sentry]

Bug: The getFileNameAndExtension function can receive an undefined value from attachment.file?.[0]?.label, causing a runtime crash when .lastIndexOf() is called on it.
_{Severity: HIGH}

Suggested Fix

Provide a fallback value to the getFileNameAndExtension function to handle cases where attachment.file?.[0]?.label is undefined. A similar pattern with a fallback is used elsewhere in AttachmentList.tsx. For example: getFileNameAndExtension(attachment.file?.[0]?.label || '').

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent.
Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not
valid.

Location:
packages/twenty-front/src/modules/activities/files/components/AttachmentRow.tsx#L99-L105

Potential issue: When `isFilesFieldMigrated` is true, the code accesses
`attachment.file?.[0]?.label`. If any part of this optional chain is null or undefined,
the expression evaluates to `undefined`. This value is then passed to
`getFileNameAndExtension`, which does not handle null or undefined inputs and will crash
when calling `.lastIndexOf()`. This causes a runtime `TypeError`, preventing the
`AttachmentRow` component and the entire attachment list from rendering. The scenario is
considered realistic, especially if API users update the `file` field without providing
a `label`.

_{Did we get this right? 👍 / 👎 to inform future reviews.}

[greptile-apps]

Greptile Summary

Updates AttachmentRow to display the attachment name from the new file FILES field instead of the deprecated name field when IS_FILES_FIELD_MIGRATED feature flag is enabled.

Major issues found:

• Critical null safety bugs on lines 100-102 and 113-114 where attachment.file?.[0]?.label and attachment.file?.[0]?.url are cast to string without fallback, causing runtime errors when the file array is empty/null
• The fix addresses API users updating only the file field, but lacks defensive programming for edge cases

Confidence Score: 2/5

• This PR introduces critical runtime errors that will crash the UI when attachment.file is empty or undefined
• Score reflects two critical null safety bugs that will cause runtime errors when API users create attachments with empty or null file arrays. The code uses type assertions (as string) on potentially undefined values without fallbacks, which will crash getFileNameAndExtension function.
• AttachmentRow.tsx requires immediate fixes for null safety on lines 100-102 and 113-114 before merging

Important Files Changed

Filename	Overview
packages/twenty-front/src/modules/activities/files/components/AttachmentRow.tsx	Fixes attachment name display for FILES field migration but has critical null safety issues that could cause runtime errors

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A[AttachmentRow Component] --> B{isFilesFieldMigrated?}
    B -->|true| C[Use attachment.file field]
    B -->|false| D[Use legacy attachment.name]
    
    C --> E[Extract file0.label for name]
    C --> F[Extract file0.url for URL]
    C --> G[Extract file0.extension for category]
    
    D --> H[Use attachment.name]
    D --> I[Use attachment.fullPath]
    D --> J[Use attachment.fileCategory]
    
    E --> K[getFileNameAndExtension]
    H --> K
    
    K --> L[Split into fileName + extension]
    L --> M[Display in UI]
    
    F --> M
    I --> M
    
    style C fill:#ff6b6b
    style E fill:#ff6b6b
    style F fill:#ff6b6b
    
    Note1[Risk: file array could be empty/null]
    Note1 -.-> C

Loading

_{Last reviewed commit: 31111fa}

[greptile-apps]

_{1 file reviewed, 3 comments}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

casting potentially undefined value to string will cause runtime error if attachment.file is empty/null or label is undefined. getFileNameAndExtension expects a string and will crash on undefined.

add fallback to attachment.name:

Suggested change

	isFilesFieldMigrated
	? (attachment.file?.[0]?.label as string)
	: attachment.name,
	isFilesFieldMigrated
	? (attachment.file?.[0]?.label ?? attachment.name)
	: attachment.name,

[greptile-apps]

same null safety issue - casting undefined to string. AttachmentList.tsx:158 shows the correct pattern with fallback

Suggested change

	? (attachment.file?.[0]?.url ?? attachment.fullPath)

[greptile-apps]

imports should be alphabetically ordered per ESLint rules

[thomtrp]

maybe ensure this is not null before trying to cast? do you actually really need that casting?

[etiennejouan]

Absolutely ! I'll improve Attachment type when removing feature flag

I added a todo few lines after
https://github.com/twentyhq/twenty/pull/18073/changes/BASE..31111faeb907e352befc8b47fc4763b9ed93f05f#diff-7f7fa74b775e635071c3fcfbb5e65f9554b941d26b5d99621cb8fef0bc6c4a32R113

[github-actions]

🚀 Preview Environment Ready!

Your preview environment is available at: http://bore.pub:3380

This environment will automatically shut down when the PR is closed or after 5 hours.

[twenty-eng-sync]

Hey @etiennejouan! After you've done the QA of your Pull Request, you can mark it as done here. Thank you!