[Beta] Automatic Analysis of your repositories with SonarCloud

What does the automatic analysis do? Just examine the new code (will this update coverage) ? for projects that are examined as a single unit normally, but actually contain sources from another project, I guess these are ignored? If a project contains both supported and unsupported languages (e.g. Objective-C and Swift) should we expect any issues with counts/bugs/vulnerabilitiesm or discrepancies between autoscan and our normal scan ?