rebase: add -m/--message to rebase --collapse (issue2389) When collapsing changesets with rebase, you get a chance to edit the commit message manually, but there is no way to pass this message from the command line. This patch adds a `--message` (with short form `-m`) and `--logfile` (with short form `-m`) options to the rebase command. These options suppresses the generation of the default commit message, and instead use the message provided in the option (in case of `-m`) or in the file it points to (in case of `-l`). If you use this option without the `--collapse` option, it will raise an error. Options documentation edited by Patrick Mezard <pmezard@gmail.com>

  $ hg init
  $ echo a > a
  $ hg add a
  $ hg commit -m test

Do we ever miss a sub-second change?:

  $ for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20; do
  >     hg co -qC 0
  >     echo b > a
  >     hg st
  > done
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a
  M a