Random Ideas for Improvements of the Log User Interface

• Log is making its way through the revision tree backwards (i.e. from newest to oldest nodes) by default. Add a switch --forward to override that, and change the direction. Furthermore, replace --last and --next with --limit, thus decoupling order and limit.
• The idea of additionally letting the user choose the direction the selected revisions are printed, has been abandoned for now.
• (Re-)define the meaning of --limit. Printing a maximum number of all ancestors or descendants regardless of their distance to the node in question seems not to be very sensible. What about this: print all members of the next generation, as long as that would not exceed the maximum number of nodes to be printed?
• Add a filtering mechanism. Let the user specify --filter <some-selector>. Revisions that are matched by the selector will be marked. Other nodes (i.e. merge nodes) are marked according to the unique-* algorithm. All marked nodes will be printed. That way we will retain a sensible graph structure, which is important when printing asciik-style graphs.
• Add some fancy aliases for the filter, like --stay-on-branch = --filter b:currentbranch. It was noted on the mailing list that you can do this with: mtn auto select b:currentbranch | mtn auto toposort -@- | xargs -n 1 mtn log --last 1 --from
• Add some heuristics for detecting special cases like that: User specifies --from a --to b with a and b being single revisions, but a being an ancestor of b (so the log would actually be empty). Probably emit a warning and simply exchange a and b.
• Note to myself: Check whether --from h:my-branch --to h:mainline is actually working.
• Some people complain --from <selector> being a bit cumbersome to type as opposed to the old -r. Is there anything we can do about that?
  • Make -r an alias for --from for log? Possibly erroring out if user tries to use -r and --to together.
  • Make -r behave like --from REV --limit=1 (maybe better to add an 'mtn review' command which is basically mtn log --from REV --limit=1 --diffs)
  • Make -b <branch> argument to mtn log a synonym for --from h:<branch>. Alternately, perhaps -b <branch> should be the syntax to follow a particular branch (or set of branches).
  • ...
• Cool idea (to be done later): Add a --context option (like in grep) that, once a revision is selected for being printed, ensures that a number of revisions around it (ancestors and descendants) gets also printed.
• Another cool idea to be done later: In the unrestricted case, while printing information for a merge revision, omit the information for nodes that are not marked.
• From the "get rid of the ChangeLog"-discussion: Add a `--gnu-log` option that prints out the log in GNU ChangeLog format.