When analyzing merge request in comparison to what branch are issues considered as NEW

This is more a question rather than issue.
I am curious, when sonar is run from gitlab pull request environment, it reports only NEW issues. I am curious when it happens with what branch comparison is happening? With pull request-target branch or pull request source branch? or with a base (master) branch?

Thank you

Hey there.

During Pull Request Analysis, changed files/lines is calculated as compared to the target branch. Essentially – the same as when you view the pull request diff in your DevOps Platform (showing the lines added and removed).

Only issues on changed lines are reported in PR analysis.