share/msysGit/rebasing-merge.sh

   1 #!/bin/sh
   2 #
   3 # Rebase 'master' on top of an upstream branch (defaults to 'junio/next').
   4 # This merges the old state of 'master' using the merge strategy 'ours'
   5 # to enable a fast-forward.
   6 #
   7 # options:
   8 #  --dry-run
   9 #     do not perform the rebase but only display the revisions selected
  10 #
  11 #  --graph
  12 #     as for dry-run but display the commits as a graph
  13 #
  14 #  --cherry
  15 #     as for --dry-run but display the commits using cherry notation to mark
  16 #     commits that are suitable for upstream consideration.
  17
  18 force=
  19 dryrun=
  20 graph=
  21 cherry=
  22 while test $# -gt 0
  23 do
  24         case "$1" in
  25         -f|--force)
  26                 force=t
  27                 ;;
  28         -s|--show|-d|--dry-run)
  29                 dryrun=t
  30                 ;;
  31         -g|--graph)
  32                 dryrun=t
  33                 graph=--graph
  34                 ;;
  35         -c|--cherry)
  36                 dryrun=t
  37                 cherry=--cherry
  38                 ;;
  39         -*)
  40                 echo "Unknown option: $1" >&2
  41                 exit 1
  42                 ;;
  43         *)
  44                 break
  45                 ;;
  46         esac
  47         shift
  48 done
  49
  50 TO=${1:-junio/next}
  51
  52 if test -z "$force" && test -z "$(git rev-list .."$TO")"
  53 then
  54         echo "Nothing new in $TO; To force a rebase, use the --force, Luke!" >&2
  55         exit 1
  56 fi
  57
  58 TODO_EXTRA="$(git rev-parse --git-dir)/todo-extra"
  59
  60 case "$(git rev-parse --symbolic-full-name HEAD)" in
  61 refs/heads/master)
  62         UPSTREAM=$(git rev-parse --symbolic-full-name HEAD@{u}) || {
  63                 echo "Not tracking any remote branch!" >&2
  64                 exit 1
  65         }
  66         test "$(git rev-parse HEAD)" = "$(git rev-parse $UPSTREAM)" ||
  67         test "$(git rev-parse master@{1})" = "$(git rev-parse $UPSTREAM)" || {
  68                 echo "Your 'master' is not up-to-date!" >&2
  69                 exit 1
  70         }
  71         ;; # okay
  72 HEAD) ;; # okay
  73 *)
  74         echo "Not on 'master'!" >&2
  75         exit 1
  76         ;;
  77 esac
  78
  79 is_ours_merge () {
  80         test "$(git rev-parse $1:)" = "$(git rev-parse "$1^:")"
  81 }
  82
  83 list_merges () {
  84         git rev-list --parents "$@" | sed -n 's/ .* .*//p'
  85 }
  86
  87 # Find old rebasing merge, if any
  88
  89 PREVIOUS_REBASING=
  90 for commit in $(list_merges $TO..)
  91 do
  92         if is_ours_merge $commit
  93         then
  94                 PREVIOUS_REBASING=$commit
  95                 break
  96         fi
  97 done
  98
  99 TO_SHA1=$(git rev-parse --short $TO)
 100 MESSAGE="Rebasing merge to $TO ($TO_SHA1)"
 101 RANGE=$TO.. &&
 102 if test -n "$PREVIOUS_REBASING"
 103 then
 104         MESSAGE="$(printf "%s\n\n%s" "$MESSAGE" \
 105                 "Previous rebasing merge: $PREVIOUS_REBASING")"
 106         RANGE="$RANGE ^$PREVIOUS_REBASING^2"
 107         for commit in $(list_merges $RANGE)
 108         do
 109                 test $commit != $PREVIOUS_REBASING &&
 110                 is_ours_merge $commit &&
 111                 RANGE="$RANGE ^$commit"
 112         done
 113 fi
 114
 115 if test -n "$dryrun"
 116 then
 117         git log --oneline $graph $cherry --boundary $RANGE
 118         exit
 119 fi
 120
 121 ORIG_HEAD=$(git rev-parse HEAD)
 122 # Get commits to rebase
 123 git rev-list --format='pick %h %s (%an)' --reverse --no-merges $RANGE |
 124 grep -v '^commit ' > "$TODO_EXTRA" &&
 125 TMP_EDITOR="$(git rev-parse --git-dir)/rebasing-editor.sh" &&
 126 cat > "$TMP_EDITOR" << EOF &&
 127 #!/bin/sh
 128 case "\$1" in
 129 */git-rebase-todo)
 130         sed -e '/^[^#]/d' < "\$1" >> "$TODO_EXTRA" &&
 131         mv "$TODO_EXTRA" "\$1"
 132 esac &&
 133 exec "$(git var GIT_EDITOR)" "\$@"
 134 EOF
 135 chmod a+x "$TMP_EDITOR" &&
 136 if GIT_EDITOR="$TMP_EDITOR" git rebase --autosquash -i --onto $TO HEAD^
 137 then
 138         git merge -s ours -m "$MESSAGE" $ORIG_HEAD
 139 else
 140         FINISH="$(git rev-parse --git-dir)/finish-rebasing-merge.sh"
 141         cat > "$FINISH" << EOF
 142 #!/bin/sh
 143 git merge -s ours -m '$MESSAGE' $ORIG_HEAD
 144 EOF
 145         chmod a+x "$FINISH"
 146         cat << EOF
 147
 148 After the rebase, call '$FINISH' manually
 149 EOF
 150 fi