The class trigger::TriggerEvent is part of the RAW data, and any changes must be backwards compatible. In order to ensure it can be read by all future CMSSW releases, there is a TestTriggerEventFormat unit test, which makes use of the TestReadTriggerEvent analyzer and the TestWriteTriggerEvent producer. The unit test checks that the object can be read properly from
- a file written by the same release
- files written by (some) earlier releases
If the persistent format of class trigger::TriggerEvent gets changed in the future, please adjust the TestReadTriggerEvent and TestWriteTriggerEvent modules accordingly. It is important that every member container has some content in this test. Please also add a new file to the https://github.com/cms-data/DataFormats-HLTReco/ repository, and update the TestTriggerEventFormat unit test to read the newly created file. The file name should contain the release or pre-release with which it was written.