git-merge-driver

for merges conducted by the hosting platform (e.g. merges created by github.com pull request workflow). One idea I had at the time was using external schema files (e.g. JSON schema for JSON files) to help guide/constrain the result of the merge. I never implemented it, but it should be possible. If the schemas were also version controlled in the same git repo that stores the data, you'd need to figure out which one (and which version) to load when resolving a merge conflict of a data file. There doesn't seem to be a well-supported robust way for a merge driver script to discover the source and destination branches, but there are some potentially fragile ways of doing it that work some of the time.

ver for merging data files in a game engine: http://bitsquid.blogspot.com/2010/06/avoiding-content-locks-... In this gamedev context of merging game data files, it was less important to produce the "correct" merge result than it was to produce some result that had a valid file format. Less technical users could then fix up bad mergetool decisions in an editor with a UI instead of trying to resolve the merge conflicts at the level of the raw serialisation format itself (which could corrupt the data file and make it not possible to load into the editor). In other situations where there is a large cost to automatically producing the wrong merge result, it would be a better tradeoff to "halt the line" if there is ambiguity about how a merge should be resolved, and escalate to a human to decide what to do. Further reading: How to wire a custom merge driver in to git: https://git-scm.com/docs/gitattributes#_defining_a_custom_me... What values you can pass in to a merge driver on the command line: https://github.com/git/git/blob/f1d4a28250629ae469fc5dd59ab8... Simple example of the plumbing to wire in a merge driver, with a trivial dumb driver script: https://github.com/Praqma/git-merge-driver