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