rebase-i-p: delay saving current-commit to REWRITTEN if squashing

diff --git a/git-rebase--interactive.sh b/git-rebase--interactive.sh
index ec4299ae30d06a6a19f5108b00dc8bc9ccd65cb0..23cf7a5d682183a96e825a5e346f75e8e2f9b4c1 100755 (executable)
--- a/git-rebase--interactive.sh
+++ b/git-rebase--interactive.sh
@@ -37,6 +37,7 @@ DONE="$DOTEST"/done
 MSG="$DOTEST"/message
 SQUASH_MSG="$DOTEST"/message-squash
 REWRITTEN="$DOTEST"/rewritten
+DROPPED="$DOTEST"/dropped
 PRESERVE_MERGES=
 STRATEGY=
 ONTO=
@@ -65,6 +66,16 @@ output () {
        esac
 }
 
+run_pre_rebase_hook () {
+       if test -x "$GIT_DIR/hooks/pre-rebase"
+       then
+               "$GIT_DIR/hooks/pre-rebase" ${1+"$@"} || {
+                       echo >&2 "The pre-rebase hook refused to rebase."
+                       exit 1
+               }
+       fi
+}
+
 require_clean_work_tree () {
        # test if working tree is dirty
        git rev-parse --verify HEAD > /dev/null &&
@@ -159,18 +170,27 @@ pick_one_preserving_merges () {
 
        if test -f "$DOTEST"/current-commit
        then
-               current_commit=$(cat "$DOTEST"/current-commit) &&
-               git rev-parse HEAD > "$REWRITTEN"/$current_commit &&
-               rm "$DOTEST"/current-commit ||
-               die "Cannot write current commit's replacement sha1"
+               if [ "$fast_forward" == "t" ]
+               then
+                       cat "$DOTEST"/current-commit | while read current_commit
+                       do
+                               git rev-parse HEAD > "$REWRITTEN"/$current_commit
+                       done
+                       rm "$DOTEST"/current-commit ||
+                       die "Cannot write current commit's replacement sha1"
+               fi
        fi
 
-       echo $sha1 > "$DOTEST"/current-commit
+       echo $sha1 >> "$DOTEST"/current-commit
 
        # rewrite parents; if none were rewritten, we can fast-forward.
        new_parents=
-       for p in $(git rev-list --parents -1 $sha1 | cut -d' ' -f2-)
+       pend=" $(git rev-list --parents -1 $sha1 | cut -d' ' -f2-)"
+       while [ "$pend" != "" ]
        do
+               p=$(expr "$pend" : ' \([^ ]*\)')
+               pend="${pend# $p}"
+
                if test -f "$REWRITTEN"/$p
                then
                        new_p=$(cat "$REWRITTEN"/$p)
@@ -183,7 +203,13 @@ pick_one_preserving_merges () {
                                ;;
                        esac
                else
-                       new_parents="$new_parents $p"
+                       if test -f "$DROPPED"/$p
+                       then
+                               fast_forward=f
+                               pend=" $(cat "$DROPPED"/$p)$pend"
+                       else
+                               new_parents="$new_parents $p"
+                       fi
                fi
        done
        case $fast_forward in
@@ -267,7 +293,7 @@ do_next () {
                "$DOTEST"/amend || exit
        read command sha1 rest < "$TODO"
        case "$command" in
-       '#'*|'')
+       '#'*|''|noop)
                mark_action_done
                ;;
        pick|p)
@@ -322,7 +348,7 @@ do_next () {
                        MSG_OPT=
                        MSG_FILE=
                        rm -f "$SQUASH_MSG" || exit
-                       cp -v "$MSG" "$GIT_DIR"/SQUASH_MSG
+                       cp "$MSG" "$GIT_DIR"/SQUASH_MSG
                        rm -f "$GIT_DIR"/MERGE_MSG || exit
                        ;;
                esac
@@ -355,20 +381,7 @@ do_next () {
        HEADNAME=$(cat "$DOTEST"/head-name) &&
        OLDHEAD=$(cat "$DOTEST"/head) &&
        SHORTONTO=$(git rev-parse --short $(cat "$DOTEST"/onto)) &&
-       if test -d "$REWRITTEN"
-       then
-               test -f "$DOTEST"/current-commit &&
-                       current_commit=$(cat "$DOTEST"/current-commit) &&
-                       git rev-parse HEAD > "$REWRITTEN"/$current_commit
-               if test -f "$REWRITTEN"/$OLDHEAD
-               then
-                       NEWHEAD=$(cat "$REWRITTEN"/$OLDHEAD)
-               else
-                       NEWHEAD=$OLDHEAD
-               fi
-       else
-               NEWHEAD=$(git rev-parse HEAD)
-       fi &&
+       NEWHEAD=$(git rev-parse HEAD) &&
        case $HEADNAME in
        refs/*)
                message="$GIT_REFLOG_ACTION: $HEADNAME onto $SHORTONTO)" &&
@@ -512,6 +525,7 @@ first and then run 'git rebase --continue' again."
                ;;
        --)
                shift
+               run_pre_rebase_hook ${1+"$@"}
                test $# -eq 1 -o $# -eq 2 || usage
                test -d "$DOTEST" &&
                        die "Interactive rebase already started"
@@ -573,6 +587,7 @@ first and then run 'git rebase --continue' again."
                        --abbrev=7 --reverse --left-right --cherry-pick \
                        $UPSTREAM...$HEAD | \
                        sed -n "s/^>/pick /p" > "$TODO"
+               test -s "$TODO" || echo noop >> "$TODO"
                cat >> "$TODO" << EOF
 
 # Rebase $SHORTUPSTREAM..$SHORTHEAD onto $SHORTONTO
@@ -587,6 +602,28 @@ first and then run 'git rebase --continue' again."
 #
 EOF
 
+               # Watch for commits that been dropped by --cherry-pick
+               if test t = "$PRESERVE_MERGES"
+               then
+                       mkdir "$DROPPED"
+                       # drop the --cherry-pick parameter this time
+                       git rev-list $MERGES_OPTION --abbrev-commit \
+                               --abbrev=7 $UPSTREAM...$HEAD --left-right | \
+                               sed -n "s/^>//p" | while read rev
+                       do
+                               grep --quiet "$rev" "$TODO"
+                               if [ $? -ne 0 ]
+                               then
+                                       # Use -f2 because if rev-list is telling this commit is not
+                                       # worthwhile, we don't want to track its multiple heads,
+                                       # just the history of its first-parent for others that will
+                                       # be rebasing on top of us
+                                       full=$(git rev-parse $rev)
+                                       git rev-list --parents -1 $rev | cut -d' ' -f2 > "$DROPPED"/$full
+                               fi
+                       done
+               fi
+
                has_action "$TODO" ||
                        die_abort "Nothing to do"