`git log` does this. Filter by --author or --grep to find the task ID or whatever. If you want to produce a sum-total set of changes... it's a dubious/impreci

`git log` does this. Filter by --author or --grep to find the task ID or whatever. If you want to produce a sum-total set of changes... it's a dubious/imprecise desire, as intervening changes may affect the result. But you can still do a potentially-good-enough job by cherry picking commits you're interested in from a common ancestor, and diffing the end result against the ancestor you started from. If the cherry-picks don't apply cleanly, there's no straightforward diff or answer, and then it's of course much more complex. --- edit: or I just googled around a little, and if all you want is the sum of all changes in arbitrary commits that you can find with log: `git log -p | diffstat` if you add -> remove -> restore a line, it'll count that as 2 additions and 1 removal.