[PATCH 00/14] Make git-pull a builtin

This series directly depends on the changes made in jc/merge and pt/pull-tests. The commit messages assume that the behavioral changes proposed in pt/pull-log-n, pt/pull-tags-error-diag, pt/pull-ff-vs-merge-ff, and [1] have been introduced.

git-pull is a commonly executed command to check for new changes in the upstream repository and, if there are, fetch and integrate them into the current branch. Currently it is implemented by the shell script git-pull.sh. However, compared to C, shell scripts have certain deficiencies:

1. Usually have to rely on spawning a lot of processes, which can be slow on
   systems that do not implement copy-on-write semantics.

2. They introduce a lot of dependencies, especially on non-POSIX systems.

3. They cannot take advantage of git's C API and internal caches.

This series rewrites git-pull.sh into a C builtin, thus improving its performance and portability. It is part of my GSoC project to rewrite git-pull and git-am into builtins[2].

[1] http://thread.gmane.org/gmane.comp.version-control.git/269249 [2] https://gist.github.com/pyokagan/1b7b0d1f4dab6ba3cef1

Paul Tan (14):
  pull: implement fetch + merge
  pull: pass verbosity, --progress flags to fetch and merge
  pull: pass git-merge's options to git-merge
  pull: pass git-fetch's options to git-fetch
  pull: error on no merge candidates
  pull: support pull.ff config
  pull: check if in unresolved merge state
  pull: fast-forward working tree if head is updated
  pull: implement pulling into an unborn branch
  pull: set reflog message
  pull: teach git pull about --rebase
  pull: configure --rebase via branch.<name>.rebase or pull.rebase
  pull --rebase: exit early when the working directory is dirty
  pull --rebase: error on no merge candidate cases

 Makefile                     |   2 +-
 advice.c                     |   8 +
 advice.h                     |   1 +
 builtin.h                    |   1 +
 builtin/pull.c               | 919 +++++++++++++++++++++++++++++++++++++++++++
 contrib/examples/git-pull.sh | 339 ++++++++++++++++
 git-pull.sh                  | 339 ----------------
 git.c                        |   1 +
 8 files changed, 1270 insertions(+), 340 deletions(-)
 create mode 100644 builtin/pull.c
 create mode 100755 contrib/examples/git-pull.sh
 delete mode 100755 git-pull.sh