Add collapsePreexisting setting to keep newly added comments expanded

[Copilot]

Summary

This PR adds a new collapsePreexisting option to the githubPullRequests.commentExpandState setting that addresses the issue where newly created comments immediately collapse when using the collapseAll setting.

Users can now select collapsePreexisting to collapse all pre-existing comments while keeping newly added comments expanded, allowing them to review what was just added.

Changes Made

1. Added new setting option: Added collapsePreexisting as a third option to githubPullRequests.commentExpandState setting in package.json and package.nls.json

2. Updated comment collapse logic: Modified getCommentCollapsibleState() in src/github/utils.ts to:

   • Add constant for the new setting value
   • Check if the setting is collapsePreexisting and if the comment was newly added
   • Keep newly added comments expanded when this setting is active

3. Enhanced threading functions: Updated updateThreadWithRange() and updateThread() to accept an isNewlyAdded parameter to detect when a comment thread is being added

4. Updated controllers: Modified both pullRequestCommentController.ts and reviewCommentController.ts to:

   • Pass isNewlyAdded: true when updating newly added threads
   • Intentionally omit the flag for changed/refreshed threads (so the "newly added" logic only applies once)

How It Works

When a user selects the collapsePreexisting option:

• Pre-existing comments from all users will collapse
• Newly added comments (from any user) remain expanded
• This allows users to review newly added comments before they collapse
• Once the page is refreshed or the thread is updated, the comment will collapse following normal rules

Files Modified

• package.json - Added new enum value collapsePreexisting to setting
• package.nls.json - Added localized description for new setting
• src/github/utils.ts - Updated logic to use isNewlyAdded flag
• src/view/pullRequestCommentController.ts - Pass isNewlyAdded: true for newly added threads
• src/view/reviewCommentController.ts - Pass isNewlyAdded: true for newly added threads

Testing

• ✅ TypeScript compilation passes
• ✅ Hygiene and lint checks pass
• ✅ Logic follows existing patterns in the codebase
• ✅ Detection works for any newly added comment regardless of author

Original prompt

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This section details on the original issue you should resolve

<issue_title>Please do not automatically collapse the comment I just created when using collapseAll</issue_title>
<issue_description>This is a feature request to change the behaviour of the collapseAll mode so that comments you just created do not automatically collapse.

I my opinion, collapseAll should only apply to pre-existing comments. When I post a comment I find it quite annoying that it immediately disappears, as often I want to re-read what I wrote to check the markdown rendered properly and I didn't make any mistakes or was not as clear as I could be.

Perhaps there could be a new value for the setting, called collapsePreExisting?

vscode-pr-2.mp4

I have

"githubPullRequests.commentExpandState": "collapseAll",

but would not expect a comment I just made to automatically collapse

Originally posted by @MetRonnie in #3345. The current behaviour is considered correct according to #3345 (comment)

---

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Please do not automatically collapse the comment I just created when using collapseAll #6503

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[alexr00]

@copilot Actually, add a new options to githubPullRequests.commentExpandState for collapsePreexisting and use that value instead.

[Copilot]

@copilot Actually, add a new options to githubPullRequests.commentExpandState for collapsePreexisting and use that value instead.

Done! I've added a new collapsePreexisting option to the githubPullRequests.commentExpandState setting. When this option is selected, newly created comments from the current user will remain expanded while all pre-existing comments collapse. Commit: 2392dfe

[alexr00]

@copilot don't base it off of the current user, just base it off of a comment being added.

[Copilot]

@copilot don't base it off of the current user, just base it off of a comment being added.

Updated! The logic now detects any newly added comment (regardless of author) and keeps it expanded when collapsePreexisting is selected. The implementation uses an isNewlyAdded boolean flag instead of checking the current user. Commit: 5bae2ea