[PATCH 0/3] making --first-parent imply -m

For some projects, it's useful to walk the first parent history, looking at each merge commit as a normal commit introducing all of the changes no its side branch. E.g.:

  git log --first-parent -m -Sfoo -p

might show you the topic or pull request that introduced code "foo". But I quite often forget to add "-m", and get confused that it doesn't return any results.

This series just makes --first-parent imply -m. That doesn't change any output by itself, but does mean that diff options like "-p", "-S", etc, behave sensibly.

  [1/3]: log: drop "--cc implies -m" logic
  [2/3]: revision: add "--ignore-merges" option to counteract "-m"
  [3/3]: log: enable "-m" automatically with "--first-parent"

 Documentation/rev-list-options.txt            |  1 +
 builtin/log.c                                 |  7 +-
 revision.c                                    | 10 ++-
 revision.h                                    |  2 +-
 t/t4013-diff-various.sh                       |  1 +
 ...g_--ignore-merges_-p_--first-parent_master | 78 +++++++++++++++++++
 t/t4013/diff.log_-p_--first-parent_master     | 22 ++++++
 7 files changed, 113 insertions(+), 8 deletions(-)
 create mode 100644 t/t4013/diff.log_--ignore-merges_-p_--first-parent_master

-Peff