Testing Framework for the LHC Beam-based Feedback System

During the first LHC shut-down period, software for the LHC Beam-based Feedback Controller (BFC) and Service Unit (BFSU) was migrated to new 64-bit multi-core hardware and to a new version of CERN's FESA3 real-time framework. This coincided with the transfer of responsibility to a new software team, charged with readying the systems for beam in 2015 as well as maintaining and improving the code-base in the future. In order to facilitate the comprehension of the system's 90'000+ existing lines of code, a new testing framework was developed which would not only serve to define the system's functional specification, but also provide acceptance tests for future releases. This paper presents how the BFC and BFSU systems were decoupled from each other as well as from the LHC plant's measurement and correction systems, thus allowing simulation-data driven instances to be deployed in a test environment. It also describes the resulting Java-based domain-specific language (DSL) which, when employed in JUnit, allows the formation of repeatable acceptance tests.