[arxanas]

I believe `jj abandon` indeed operates on edges rather than nodes. It looks the diagram is updated now.

I believe that `jj squash` and `jj backout` also operate on edges rather than nodes, but the examples here don't make it clear. `jj squash` ought to combine the edge `r -> q` with the edge for `q -> parent(q)` (not depicted) and ultimately leave the `r -> q` edge as "empty", and `jj backout` ought to create an edge that has the inverse diff of another edge (which, in this case, is indistinguishable from `s`'s node changing to be equivalent to `q`'s node).

[justinpombrio]

Yup, that's all correct. I drew `squash` and `backout` in terms of files in order to avoid needing notation for the opposite of an edit and the composition of two edits.