[ninkendo]

You don’t even need to think about diff algorithms to see why a cherry-pick, merge, etc may not do what you want.

If in my branch, I rename oldFunc to newFunc in file A, and change file B to replace the call to oldFunc with newFunc; and in your branch, you add a new call to oldFunc in file C... the code will break when we merge our branches. Our changes would both pass tests independently, but would break when we merge them. No file-level diff algorithm would detect a “conflict” here.

Diff algorithms only help with saying “are two branches trying to edit the same lines of code”, but the answer to that question is never enough to tell you whether two changes logically will apply cleanly to one another.