Git Historian allows you to collect arbitrary data about a file at each point in its Git history.
Think of it as git log --follow for every file in a repo, all at once.
Why?
It can be useful for automating tasks that require knowledge of a file's history, e.g., updating each source file's copyright header with the years during which the file was modified (because Legal said so).
How?
The library gathers commit info by parsing the output of git log --name-status,
then builds a tree of the history of all files we care about.
See parsing.rs and history.rs for details.
Why Rust?
Because it's awesome (and I wanted to try it out for a Real™ project).