git edit – start interactive rebase to edit the specified commit.

git-edit

#!/bin/sh
# vim: set ts=4:
set -e

if [ $# -eq 0 ] || [ "$1" = '-h' ]; then
	cat >&2 <<-EOF
		Usage: git edit <tree-ish>
		       git edit [-h]

		Start interactive rebase to edit the specified commit.
	EOF
	exit 1
fi

if [ -n "$GIT_EDIT_COMMIT" ]; then
	# $1 is path of the message showed by "git rebase -i"; we just edit it for
	# the user.
	sed -E "s/^pick ($GIT_EDIT_COMMIT.*)/edit \1/" "$1" > /tmp/git.$$
	mv /tmp/git.$$ "$1"

else
	GIT_EDIT_COMMIT="$(git rev-parse --short $1)" \
		|| { echo "fatal: bad revision '$1'"; exit 128; }
	export GIT_EDIT_COMMIT

	# Start interactive rebase from the parent of the specified commit
	# and use this script as EDITOR.
	GIT_EDITOR="$0" git rebase -i "$GIT_EDIT_COMMIT"~1
fi

git-reword

#!/bin/sh
# vim: set ts=4:
set -e

if [ $# -eq 0 ] || [ "$1" = '-h' ]; then
	cat >&2 <<-EOF
		Usage: git reword <tree-ish>
		       git reword [-h]

		Start interactive rebase to reword the specified commit.
	EOF
	exit 1
fi

# This variable is set when git executes this script to edit the actual commit
# message. Unsetting GIT_EDITOR after 2nd step didn't prevent it, so we must
# use this hack.
if [ -n "$GIT_INDEX_FILE" ]; then
	exec ${EDITOR:-vim} "$1"

elif [ -n "$GIT_EDIT_COMMIT" ]; then
	# $1 is path of the message showed by "git rebase -i"; we just edit it for
	# the user.
	sed -E "s/^pick ($GIT_EDIT_COMMIT.*)/reword \1/" "$1" > /tmp/git.$$
	mv /tmp/git.$$ "$1"

else
	GIT_EDIT_COMMIT="$(git rev-parse --short $1)" \
		|| { echo "fatal: bad revision '$1'"; exit 128; }
	export GIT_EDIT_COMMIT

	# Start interactive rebase from the parent of the specified commit
	# and use this script as EDITOR.
	GIT_EDITOR="$0" git rebase -i "$GIT_EDIT_COMMIT"~1
fi