Enable ref log creation in git checkout -b.

Switch git checkout -b to use git-update-ref rather than echo and
a shell I/O redirection.  This is more in line with typical GIT
commands and allows -b to be logged according to the normal ref
logging rules.

Added -l option to allow users to create the ref log at the same
time as creating a branch.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/Documentation/git-checkout.txt b/Documentation/git-checkout.txt
index 0951289..0643943 100644 (file)
--- a/Documentation/git-checkout.txt
+++ b/Documentation/git-checkout.txt
@@ -8,7 +8,7 @@ git-checkout - Checkout and switch to a branch
 SYNOPSIS
 --------
 [verse]
-'git-checkout' [-f] [-b <new_branch>] [-m] [<branch>]
+'git-checkout' [-f] [-b <new_branch> [-l]] [-m] [<branch>]
 'git-checkout' [-m] [<branch>] <paths>...
 
 DESCRIPTION
@@ -37,6 +37,11 @@ OPTIONS
 -b::
        Create a new branch and start it at <branch>.
 
+-l::
+       Create the new branch's ref log.  This activates recording of
+       all changes to made the branch ref, enabling use of date
+       based sha1 expressions such as "<branchname>@{yesterday}".
+
 -m::
        If you have local modifications to one or more files that
        are different between the current branch and the branch to

diff --git a/git-checkout.sh b/git-checkout.sh
index a11c939..360aabf 100755 (executable)
--- a/git-checkout.sh
+++ b/git-checkout.sh
@@ -5,10 +5,13 @@ SUBDIRECTORY_OK=Sometimes
 . git-sh-setup
 
 old=$(git-rev-parse HEAD)
+old_name=HEAD
 new=
+new_name=
 force=
 branch=
 newbranch=
+newbranch_log=
 merge=
 while [ "$#" != "0" ]; do
     arg="$1"
@@ -24,6 +27,9 @@ while [ "$#" != "0" ]; do
                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
                ;;
@@ -44,6 +50,7 @@ while [ "$#" != "0" ]; do
                                exit 1
                        fi
                        new="$rev"
+                       new_name="$arg^0"
                        if [ -f "$GIT_DIR/refs/heads/$arg" ]; then
                                branch="$arg"
                        fi
@@ -51,9 +58,11 @@ while [ "$#" != "0" ]; do
                then
                        # checking out selected paths from a tree-ish.
                        new="$rev"
+                       new_name="$arg^{tree}"
                        branch=
                else
                        new=
+                       new_name=
                        branch=
                        set x "$arg" "$@"
                        shift
@@ -114,7 +123,7 @@ then
        cd "$cdup"
 fi
 
-[ -z "$new" ] && new=$old
+[ -z "$new" ] && new=$old && new_name="$old_name"
 
 # 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
@@ -187,9 +196,11 @@ fi
 #
 if [ "$?" -eq 0 ]; then
        if [ "$newbranch" ]; then
-               leading=`expr "refs/heads/$newbranch" : '\(.*\)/'` &&
-               mkdir -p "$GIT_DIR/$leading" &&
-               echo $new >"$GIT_DIR/refs/heads/$newbranch" || exit
+               if [ "$newbranch_log" ]; then
+                       mkdir -p $(dirname "$GIT_DIR/logs/refs/heads/$branchname")
+                       touch "$GIT_DIR/logs/refs/heads/$branchname"
+               fi
+               git-update-ref -m "checkout: Created from $new_name" "refs/heads/$newbranch" $new || exit
                branch="$newbranch"
        fi
        [ "$branch" ] &&