Pull request shows already merged changes

[Satheeskumar]

Hey there, recently we're experiencing a problem that some time new pull requests showing old commits and files changes which are already in the target branch.

And I couldn't find any proper solution from previous discussions. 

1. https://community.atlassian.com/t5/Bitbucket-questions/Target-Branch-Shows-Differences-For-Already-Merged-Changes/qaq-p/2008192
2. https://community.atlassian.com/t5/Bitbucket-questions/Pull-request-shows-commits-which-are-already-present-in-target/qaq-p/1815854

And for your information, We not sure how it's happening. But most of the time working as expected. sometime not. 

Please let me know if there any solution for this.

Thanks.

[Marius Lazar]

Hi @Theodora Boudale,

Thank you for the explanation. While I understand that the switch to the 'three-dot' diff algorithm may improve performance from a technical standpoint, I believe this change negatively impacts our workflow as users. If the performance benefits are primarily for the machine but result in disadvantages for us humans working with these diffs, then it seems counterproductive. Don't you agree that the user experience should be a top priority?

Best regards,
Marius

[Theodora Boudale]

Hi Marius,

Thank you for the feedback.

The performance benefits are not primarily for the machine. Many users creating pull requests with very large diffs were unable to view those diffs in Bitbucket Cloud with the old diff algorithm.

I understand that this is not the case with all users and many teams work with smaller diffs. If you sync the source branch of the PR with the destination branch, you'll be able to see the destination branch's changes reflected in the diff, as long as the size of the diff is within our limits:

• https://support.atlassian.com/bitbucket-cloud/docs/limits-for-viewing-content-and-diffs/

Please also make sure you add your vote and feedback to this feature request:

• https://jira.atlassian.com/browse/BCLOUD-21964

Kind regards,
Theodora

[Theodora Boudale]

Hi @Satheeskumar,

We have changed the diff algorithm from what we call a '3-way' diff to a 2-way 'three-dot' diff in order to improve performance on complex diffs:

https://bitbucket.org/blog/improving-performance-on-complex-diffs

The '3-way' diff includes changes to the destination branch, whereas the 'three-dot' diff does not reflect changes made to the destination branch since the source branch was created from the destination branch.

In the case where files changed in the source branch are the same files as those changed in the destination branch, the 'three-dot' diff will show only the changes introduced in the source branch.

There is no way to switch to the '3-way' diff algorithm at the moment, we have a request to provide that on demand: https://jira.atlassian.com/browse/BCLOUD-21964

If you want to see changes to the destination branch in a PR, you can merge the destination branch into the source branch. The blog post I shared above provides more details in the section "How to see changes to the destination branch in a pull request".

Kind regards,
Theodora

[Satheeskumar]

Thanks.
I'll check this solution when I face the issue next time.

Once again thank you for your considerations.

[Theodora Boudale]

You are very welcome, please feel free to reach out if you have any other questions.

[PauloM]

Hello! I also have the same issue, it's really annoying. Do you have plans to fix it?

Thanks.

[Theodora Boudale]

Hi Paulo and welcome to the community!

I shared in my previous reply the request to provide the Preview-merge diff type on demand: https://jira.atlassian.com/browse/BCLOUD-21964

We don't have plans to work on this in the next 12 months, but we will continue to consider it in future planning and will provide periodic updates on that ticket.

Kind regards,
Theodora