[PATCH] Make git-commit cleverer - have it figure out whether it needs -a automatically

[Andy Parkins <andyparkins@gmail.com>]

Raimund Bauer offered this suggestion (paraphrased):

"Maybe we could do git-commit -a  _only_ if the index matches HEAD, and
otherwise keep current behavior?  So people who don't care about the
index won't get tripped up, and when you do have a dirty index, you get
told about it?"

Johannes Schindelin pointed out that this isn't the right thing to do for
an --amend, so that is checked for. Additionally, it's probably not the
right thing to do if any files are specified with "--only" or
"--include", so they turn this behaviour off as well.

Nguyen Thai Ngoc Duy asked that git-commit let you know it's done this
by adding an extra comment to the commit message.

Signed-off-by: Andy Parkins <andyparkins@gmail.com>
---
 git-commit.sh |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/git-commit.sh b/git-commit.sh
index 81c3a0c..b391257 100755
--- a/git-commit.sh
+++ b/git-commit.sh
@@ -265,6 +265,16 @@ $1"
 done
 case "$edit_flag" in t) no_edit= ;; esac
 
+# Clever commit - if this commit would do nothing, then make it an "all"
+# commit
+if [ -z "$(git-diff-index --cached --name-only HEAD)" \
+	-a -z "$amend" -a -z "$only" -a -z "$also" ]; then
+	echo "# There was nothing to commit but changes were detected in the" > $GIT_DIR/SQUASH_MSG
+	echo "# working tree. 'git commit -a' mode activated." >> $GIT_DIR/SQUASH_MSG
+	echo "#" >> $GIT_DIR/SQUASH_MSG
+	all=t
+fi
+
 ################################################################
 # Sanity check options
 
-- 
1.4.4.1.g3ece-dirty