We have our code in Bitbucket and use Azure DevOps build pipelines for CI builds of our iOS and Android mobile apps.

Azure DevOps build pipelines have a build trigger option to validate pull requests. When a developer creates or updates a PR, the trigger builds that PR feature branch and reports the build status in the Bitbucket PR page.

We'd like to see the Bitbucket capability expanded to allow the merge commit to be built. Or the future merge commit, if you will; the combination of code from the feature branch + the code of the target branch. This will help us better validate that the feature branch doesn't contain any breaking changes with the trunk or target branch, prodiving confidence that the PR is ready to be merged.

From Microsoft's documentation on this feature:
"Each new run builds the latest commit from the source branch of the pull request. This is different from how Azure Pipelines builds pull requests in other repositories (e.g., Azure Repos or GitHub), where it builds the merge commit. Unfortunately, Bitbucket does not expose information about the merge commit, which contains the merged code between the source and target branches of the pull request."

https://docs.microsoft.com/en-us/azure/devops/pipelines/repos/bitbucket?view=azure-devops&tabs=yaml#pr-triggers