Merge branch 'lt/core-optim'

diff --git a/git-rebase.sh b/git-rebase.sh
index 60c458f201f8f98bb1c6e115c009525659c2ee20..9b13b833cb5762542848ee3e85e23d3ca0f76fa6 100755 (executable)
--- a/git-rebase.sh
+++ b/git-rebase.sh
@@ -309,22 +309,42 @@ then
        }
 fi
 
-# If the branch to rebase is given, first switch to it.
+# If the branch to rebase is given, that is the branch we will rebase
+# $branch_name -- branch being rebased, or HEAD (already detached)
+# $orig_head -- commit object name of tip of the branch before rebasing
+# $head_name -- refs/heads/<that-branch> or "detached HEAD"
+switch_to=
 case "$#" in
 2)
+       # Is it "rebase other $branchname" or "rebase other $commit"?
        branch_name="$2"
-       git-checkout "$2" || usage
+       switch_to="$2"
+
+       if git show-ref --verify --quiet -- "refs/heads/$2" &&
+          branch=$(git rev-parse --verify "refs/heads/$2" 2>/dev/null)
+       then
+               head_name="refs/heads/$2"
+       elif branch=$(git rev-parse --verify "$2" 2>/dev/null)
+       then
+               head_name="detached HEAD"
+       else
+               usage
+       fi
        ;;
 *)
+       # Do not need to switch branches, we are already on it.
        if branch_name=`git symbolic-ref -q HEAD`
        then
+               head_name=$branch_name
                branch_name=`expr "z$branch_name" : 'zrefs/heads/\(.*\)'`
        else
+               head_name="detached HEAD"
                branch_name=HEAD ;# detached
        fi
+       branch=$(git rev-parse --verify "${branch_name}^0") || exit
        ;;
 esac
-branch=$(git rev-parse --verify "${branch_name}^0") || exit
+orig_head=$branch
 
 # Now we are rebasing commits $upstream..$branch on top of $onto
 
@@ -335,6 +355,8 @@ if test "$upstream" = "$onto" && test "$mb" = "$onto" &&
        # linear history?
        ! git rev-list --parents "$onto".."$branch" | grep " .* " > /dev/null
 then
+       # Lazily switch to the target branch if needed...
+       test -z "$switch_to" || git checkout "$switch_to"
        echo >&2 "Current branch $branch_name is up to date."
        exit 0
 fi
@@ -346,22 +368,11 @@ then
        GIT_PAGER='' git diff --stat --summary "$mb" "$onto"
 fi
 
-# move to a detached HEAD
-orig_head=$(git rev-parse HEAD^0)
-head_name=$(git symbolic-ref HEAD 2> /dev/null)
-case "$head_name" in
-'')
-       head_name="detached HEAD"
-       ;;
-*)
-       git checkout "$orig_head" > /dev/null 2>&1 ||
-               die "could not detach HEAD"
-       ;;
-esac
-
-# Rewind the head to "$onto"; this saves our current head in ORIG_HEAD.
+# Detach HEAD and reset the tree
 echo "First, rewinding head to replay your work on top of it..."
-git-reset --hard "$onto"
+git checkout "$onto^0" >/dev/null 2>&1 ||
+       die "could not detach HEAD"
+# git reset --hard "$onto^0"
 
 # If the $onto is a proper descendant of the tip of the branch, then
 # we just fast forwarded.
@@ -374,7 +385,8 @@ fi
 
 if test -z "$do_merge"
 then
-       git format-patch -k --stdout --full-index --ignore-if-in-upstream "$upstream"..ORIG_HEAD |
+       git format-patch -k --stdout --full-index --ignore-if-in-upstream \
+               "$upstream..$orig_head" |
        git am $git_am_opt --rebasing --resolvemsg="$RESOLVEMSG" &&
        move_to_original_branch
        ret=$?
@@ -397,7 +409,7 @@ echo "$orig_head" > "$dotest/orig-head"
 echo "$head_name" > "$dotest/head-name"
 
 msgnum=0
-for cmt in `git rev-list --reverse --no-merges "$upstream"..ORIG_HEAD`
+for cmt in `git rev-list --reverse --no-merges "$upstream..$orig_head"`
 do
        msgnum=$(($msgnum + 1))
        echo "$cmt" > "$dotest/cmt.$msgnum"