#!/bin/sh
-. git-sh-setup || die "Not a git archive"
-old=$(git-rev-parse HEAD)
+USAGE='[-q] [-f] [-b <new_branch>] [-m] [<branch>] [<paths>...]'
+SUBDIRECTORY_OK=Sometimes
+. git-sh-setup
+require_work_tree
+
+old_name=HEAD
+old=$(git-rev-parse --verify $old_name 2>/dev/null)
+oldbranch=$(git-symbolic-ref $old_name 2>/dev/null)
new=
+new_name=
force=
branch=
newbranch=
+newbranch_log=
+merge=
+quiet=
+LF='
+'
while [ "$#" != "0" ]; do
arg="$1"
shift
shift
[ -z "$newbranch" ] &&
die "git checkout: -b needs a branch name"
- [ -e "$GIT_DIR/refs/heads/$newbranch" ] &&
+ git-show-ref --verify --quiet -- "refs/heads/$newbranch" &&
die "git checkout: branch $newbranch already exists"
+ git-check-ref-format "heads/$newbranch" ||
+ die "git checkout: we do not like '$newbranch' as a branch name."
+ ;;
+ "-l")
+ newbranch_log=1
;;
"-f")
force=1
;;
+ -m)
+ merge=1
+ ;;
+ "-q")
+ quiet=1
+ ;;
+ --)
+ break
+ ;;
+ -*)
+ usage
+ ;;
*)
- rev=$(git-rev-parse --verify "$arg^0" 2>/dev/null) ||
- die "hey dummy, branch '$arg' doesn't exist."
- if [ -z "$rev" ]; then
- echo "unknown flag $arg"
- exit 1
- fi
- if [ "$new" ]; then
- echo "Multiple revisions?"
- exit 1
- fi
- new="$rev"
- if [ -f "$GIT_DIR/refs/heads/$arg" ]; then
- branch="$arg"
+ if rev=$(git-rev-parse --verify "$arg^0" 2>/dev/null)
+ then
+ if [ -z "$rev" ]; then
+ echo "unknown flag $arg"
+ exit 1
+ fi
+ new="$rev"
+ new_name="$arg"
+ if git-show-ref --verify --quiet -- "refs/heads/$arg"
+ then
+ branch="$arg"
+ fi
+ elif rev=$(git-rev-parse --verify "$arg^{tree}" 2>/dev/null)
+ then
+ # checking out selected paths from a tree-ish.
+ new="$rev"
+ new_name="$arg^{tree}"
+ branch=
+ else
+ new=
+ new_name=
+ branch=
+ set x "$arg" "$@"
+ shift
fi
+ case "$1" in
+ --)
+ shift ;;
+ esac
+ break
;;
esac
done
-[ -z "$new" ] && new=$old
+case "$force$merge" in
+11)
+ die "git checkout: -f and -m are incompatible"
+esac
+
+# The behaviour of the command with and without explicit path
+# parameters is quite different.
#
-# If we don't have an old branch that we're switching to,
-# and we don't have a new branch name for the target we
-# are switching to, then we'd better just be checking out
-# what we already had
+# Without paths, we are checking out everything in the work tree,
+# possibly switching branches. This is the traditional behaviour.
#
-[ -z "$branch$newbranch" ] &&
- [ "$new" != "$old" ] &&
- die "git checkout: you need to specify a new branch name"
+# With paths, we are _never_ switching branch, but checking out
+# the named paths from either index (when no rev is given),
+# or the named tree-ish (when rev is given).
+
+if test "$#" -ge 1
+then
+ hint=
+ if test "$#" -eq 1
+ then
+ hint="
+Did you intend to checkout '$@' which can not be resolved as commit?"
+ fi
+ if test '' != "$newbranch$force$merge"
+ then
+ die "git checkout: updating paths is incompatible with switching branches/forcing$hint"
+ fi
+ if test '' != "$new"
+ then
+ # from a specific tree-ish; note that this is for
+ # rescuing paths and is never meant to remove what
+ # is not in the named tree-ish.
+ git-ls-tree --full-name -r "$new" "$@" |
+ git-update-index --index-info || exit $?
+ fi
+
+ # Make sure the request is about existing paths.
+ git-ls-files --error-unmatch -- "$@" >/dev/null || exit
+ git-ls-files -- "$@" |
+ git-checkout-index -f -u --stdin
+ exit $?
+else
+ # Make sure we did not fall back on $arg^{tree} codepath
+ # since we are not checking out from an arbitrary tree-ish,
+ # but switching branches.
+ if test '' != "$new"
+ then
+ git-rev-parse --verify "$new^{commit}" >/dev/null 2>&1 ||
+ die "Cannot switch branch to a non-commit."
+ fi
+fi
+
+# We are switching branches and checking out trees, so
+# we *NEED* to be at the toplevel.
+cd_to_toplevel
+
+[ -z "$new" ] && new=$old && new_name="$old_name"
+
+# If we don't have an existing branch that we're switching to,
+# and we don't have a new branch name for the target we
+# are switching to, then we are detaching our HEAD from any
+# branch. However, if "git checkout HEAD" detaches the HEAD
+# from the current branch, even though that may be logically
+# correct, it feels somewhat funny. More importantly, we do not
+# want "git checkout" nor "git checkout -f" to detach HEAD.
+
+detached=
+detach_warn=
+
+if test -z "$branch$newbranch" && test "$new" != "$old"
+then
+ detached="$new"
+ if test -n "$oldbranch" && test -z "$quiet"
+ then
+ detach_warn="Note: moving to \"$new_name\" which isn't a local branch
+If you want to create a new branch from this checkout, you may do so
+(now or later) by using -b with the checkout command again. Example:
+ git checkout -b <new_branch_name>"
+ fi
+elif test -z "$oldbranch" && test -z "$quiet"
+then
+ echo >&2 "Previous HEAD position was $old"
+fi
+
+if [ "X$old" = X ]
+then
+ if test -z "$quiet"
+ then
+ echo >&2 "warning: You appear to be on a branch yet to be born."
+ echo >&2 "warning: Forcing checkout of $new_name."
+ fi
+ force=1
+fi
if [ "$force" ]
then
- git-read-tree --reset $new &&
- git-checkout-index -q -f -u -a
+ git-read-tree --reset -u $new
else
git-update-index --refresh >/dev/null
- git-read-tree -m -u $old $new
+ merge_error=$(git-read-tree -m -u --exclude-per-directory=.gitignore $old $new 2>&1) || (
+ case "$merge" in
+ '')
+ echo >&2 "$merge_error"
+ exit 1 ;;
+ esac
+
+ # Match the index to the working tree, and do a three-way.
+ git diff-files --name-only | git update-index --remove --stdin &&
+ work=`git write-tree` &&
+ git read-tree --reset -u $new || exit
+
+ eval GITHEAD_$new=${new_name:-${branch:-$new}} &&
+ eval GITHEAD_$work=local &&
+ export GITHEAD_$new GITHEAD_$work &&
+ git merge-recursive $old -- $new $work
+
+ # Do not register the cleanly merged paths in the index yet.
+ # this is not a real merge before committing, but just carrying
+ # the working tree changes along.
+ unmerged=`git ls-files -u`
+ git read-tree --reset $new
+ case "$unmerged" in
+ '') ;;
+ *)
+ (
+ z40=0000000000000000000000000000000000000000
+ echo "$unmerged" |
+ sed -e 's/^[0-7]* [0-9a-f]* /'"0 $z40 /"
+ echo "$unmerged"
+ ) | git update-index --index-info
+ ;;
+ esac
+ exit 0
+ )
+ saved_err=$?
+ if test "$saved_err" = 0 && test -z "$quiet"
+ then
+ git diff-index --name-status "$new"
+ fi
+ (exit $saved_err)
fi
#
-# Switch the HEAD pointer to the new branch if it we
+# Switch the HEAD pointer to the new branch if we
# checked out a branch head, and remove any potential
# old MERGE_HEAD's (subsequent commits will clearly not
# be based on them, since we re-set the index)
#
if [ "$?" -eq 0 ]; then
if [ "$newbranch" ]; then
- echo $new > "$GIT_DIR/refs/heads/$newbranch"
+ if [ "$newbranch_log" ]; then
+ mkdir -p $(dirname "$GIT_DIR/logs/refs/heads/$newbranch")
+ touch "$GIT_DIR/logs/refs/heads/$newbranch"
+ fi
+ git-update-ref -m "checkout: Created from $new_name" "refs/heads/$newbranch" $new || exit
branch="$newbranch"
fi
- [ "$branch" ] && ln -sf "refs/heads/$branch" "$GIT_DIR/HEAD"
+ if test -n "$branch"
+ then
+ GIT_DIR="$GIT_DIR" git-symbolic-ref -m "checkout: moving to $branch" HEAD "refs/heads/$branch"
+ if test -z "$quiet"
+ then
+ echo >&2 "Switched to${newbranch:+ a new} branch \"$branch\""
+ fi
+ elif test -n "$detached"
+ then
+ # NEEDSWORK: we would want a command to detach the HEAD
+ # atomically, instead of this handcrafted command sequence.
+ # Perhaps:
+ # git update-ref --detach HEAD $new
+ # or something like that...
+ #
+ git-rev-parse HEAD >"$GIT_DIR/HEAD.new" &&
+ mv "$GIT_DIR/HEAD.new" "$GIT_DIR/HEAD" &&
+ git-update-ref -m "checkout: moving to $arg" HEAD "$detached" ||
+ die "Cannot detach HEAD"
+ if test -n "$detach_warn"
+ then
+ echo >&2 "$detach_warn"
+ fi
+ fi
rm -f "$GIT_DIR/MERGE_HEAD"
else
exit 1