git-stash.sh

   1 #!/bin/sh
   2 # Copyright (c) 2007, Nanako Shiraishi
   3
   4 USAGE='[ | list | show | apply | clear]'
   5
   6 SUBDIRECTORY_OK=Yes
   7 . git-sh-setup
   8 require_work_tree
   9 cd_to_toplevel
  10
  11 TMP="$GIT_DIR/.git-stash.$$"
  12 trap 'rm -f "$TMP-*"' 0
  13
  14 ref_stash=refs/stash
  15
  16 no_changes () {
  17         git diff-index --quiet --cached HEAD &&
  18         git diff-files --quiet
  19 }
  20
  21 clear_stash () {
  22         if current=$(git rev-parse --verify $ref_stash 2>/dev/null)
  23         then
  24                 git update-ref -d refs/stash $current
  25         fi
  26 }
  27
  28 save_stash () {
  29         stash_msg="$1"
  30
  31         if no_changes
  32         then
  33                 echo >&2 'No local changes to save'
  34                 exit 0
  35         fi
  36         test -f "$GIT_DIR/logs/$ref_stash" ||
  37                 clear_stash || die "Cannot initialize stash"
  38
  39         # Make sure the reflog for stash is kept.
  40         : >>"$GIT_DIR/logs/$ref_stash"
  41
  42         # state of the base commit
  43         if b_commit=$(git rev-parse --verify HEAD)
  44         then
  45                 head=$(git log --abbrev-commit --pretty=oneline -n 1 HEAD)
  46         else
  47                 die "You do not have the initial commit yet"
  48         fi
  49
  50         if branch=$(git symbolic-ref -q HEAD)
  51         then
  52                 branch=${branch#refs/heads/}
  53         else
  54                 branch='(no branch)'
  55         fi
  56         msg=$(printf '%s: %s' "$branch" "$head")
  57
  58         # state of the index
  59         i_tree=$(git write-tree) &&
  60         i_commit=$(printf 'index on %s' "$msg" |
  61                 git commit-tree $i_tree -p $b_commit) ||
  62                 die "Cannot save the current index state"
  63
  64         # state of the working tree
  65         w_tree=$( (
  66                 rm -f "$TMP-index" &&
  67                 cp -p ${GIT_INDEX_FILE-"$GIT_DIR/index"} "$TMP-index" &&
  68                 GIT_INDEX_FILE="$TMP-index" &&
  69                 export GIT_INDEX_FILE &&
  70                 git read-tree -m $i_tree &&
  71                 git add -u &&
  72                 git write-tree &&
  73                 rm -f "$TMP-index"
  74         ) ) ||
  75                 die "Cannot save the current worktree state"
  76
  77         # create the stash
  78         if test -z "$stash_msg"
  79         then
  80                 stash_msg=$(printf 'WIP on %s' "$msg")
  81         else
  82                 stash_msg=$(printf 'On %s: %s' "$branch" "$stash_msg")
  83         fi
  84         w_commit=$(printf '%s\n' "$stash_msg" |
  85                 git commit-tree $w_tree -p $b_commit -p $i_commit) ||
  86                 die "Cannot record working tree state"
  87
  88         git update-ref -m "$stash_msg" $ref_stash $w_commit ||
  89                 die "Cannot save the current status"
  90         printf >&2 'Saved "%s"\n' "$stash_msg"
  91 }
  92
  93 have_stash () {
  94         git rev-parse --verify $ref_stash >/dev/null 2>&1
  95 }
  96
  97 list_stash () {
  98         have_stash || return 0
  99         git log --pretty=oneline -g "$@" $ref_stash |
 100         sed -n -e 's/^[.0-9a-f]* refs\///p'
 101 }
 102
 103 show_stash () {
 104         flags=$(git rev-parse --no-revs --flags "$@")
 105         if test -z "$flags"
 106         then
 107                 flags=--stat
 108         fi
 109         s=$(git rev-parse --revs-only --no-flags --default $ref_stash "$@")
 110
 111         w_commit=$(git rev-parse --verify "$s") &&
 112         b_commit=$(git rev-parse --verify "$s^") &&
 113         git diff $flags $b_commit $w_commit
 114 }
 115
 116 apply_stash () {
 117         git diff-files --quiet ||
 118                 die 'Cannot restore on top of a dirty state'
 119
 120         unstash_index=
 121         case "$1" in
 122         --index)
 123                 unstash_index=t
 124                 shift
 125         esac
 126
 127         # current index state
 128         c_tree=$(git write-tree) ||
 129                 die 'Cannot apply a stash in the middle of a merge'
 130
 131         # stash records the work tree, and is a merge between the
 132         # base commit (first parent) and the index tree (second parent).
 133         s=$(git rev-parse --revs-only --no-flags --default $ref_stash "$@") &&
 134         w_tree=$(git rev-parse --verify "$s:") &&
 135         b_tree=$(git rev-parse --verify "$s^1:") &&
 136         i_tree=$(git rev-parse --verify "$s^2:") ||
 137                 die "$*: no valid stashed state found"
 138
 139         unstashed_index_tree=
 140         if test -n "$unstash_index" && test "$b_tree" != "$i_tree"
 141         then
 142                 git diff --binary $s^2^..$s^2 | git apply --cached
 143                 test $? -ne 0 &&
 144                         die 'Conflicts in index. Try without --index.'
 145                 unstashed_index_tree=$(git-write-tree) ||
 146                         die 'Could not save index tree'
 147                 git reset
 148         fi
 149
 150         eval "
 151                 GITHEAD_$w_tree='Stashed changes' &&
 152                 GITHEAD_$c_tree='Updated upstream' &&
 153                 GITHEAD_$b_tree='Version stash was based on' &&
 154                 export GITHEAD_$w_tree GITHEAD_$c_tree GITHEAD_$b_tree
 155         "
 156
 157         if git-merge-recursive $b_tree -- $c_tree $w_tree
 158         then
 159                 # No conflict
 160                 a="$TMP-added" &&
 161                 git diff --cached --name-only --diff-filter=A $c_tree >"$a" &&
 162                 git read-tree --reset $c_tree &&
 163                 git update-index --add --stdin <"$a" ||
 164                         die "Cannot unstage modified files"
 165                 rm -f "$a"
 166                 if test -n "$unstashed_index_tree"
 167                 then
 168                         git read-tree "$unstashed_index_tree"
 169                 fi
 170                 git status || :
 171         else
 172                 # Merge conflict; keep the exit status from merge-recursive
 173                 status=$?
 174                 if test -n "$unstash_index"
 175                 then
 176                         echo >&2 'Index was not unstashed.'
 177                 fi
 178                 exit $status
 179         fi
 180 }
 181
 182 # Main command set
 183 case "$1" in
 184 list)
 185         shift
 186         if test $# = 0
 187         then
 188                 set x -n 10
 189                 shift
 190         fi
 191         list_stash "$@"
 192         ;;
 193 show)
 194         shift
 195         show_stash "$@"
 196         ;;
 197 apply)
 198         shift
 199         apply_stash "$@"
 200         ;;
 201 clear)
 202         clear_stash
 203         ;;
 204 help | usage)
 205         usage
 206         ;;
 207 *)
 208         if test $# -gt 0 && test "$1" = save
 209         then
 210                 shift
 211         fi
 212         save_stash "$*" && git-reset --hard
 213         ;;
 214 esac