Towards an Interoperable Textual Format for Model Differences Reporting

Managing the evolution of models becomes an extra requirement when adopting model-based software development approaches and technologies. When models are versioned using text-based version control systems (VCSs) such as Git, the reporting of differences is done by means of line-based diff operations over the model files, as it happens with the rest of the source code. Some model persistence formats are very verbose (e.g. XML Metadata Interchange (XMI)), which can make impractical or directly impossible to understand and take advantage of diff reports. We present munidiff: a text-based alternative format for reporting model differences that is compatible with the unified format, i.e. the existing de facto format to represent the output of line-based diff operations. This format is more concise than using a diff over XMI-persisted models, and its syntax to represent model differences can be customised. Using a comprehensive test suite from an existing model comparison technology (EMF Compare), we validate the completeness of this format to represent model differences, and its conciseness benefits over using a line-based diff. We also showcase how to generate a report in this format for model comparisons carried out by EMF Compare.