contrib: remove "git-resurrect.sh"

The "git-resurrect.sh" script can be used to find traces of a branch tip
in the reflog and resurrect that branch. Despite a couple of global
cleanups, the script hasn't seen any activity since it was introduced in
e1ff064e1bf (contrib git-resurrect: find traces of a branch name and
resurrect it, 2009-02-04).

Furthermore, the tool does not work with the "reftable" backend at all
as it directly reads ".git/logs/HEAD". As reflogs are stored as part of
the individual tables though that file wouldn't exist in a "reftable"-
enabled repository.

Last but not least, the tool doesn't even work unless it is explicitly
invoked via `git resurrect` as it sources "git-sh-setup". As none of our
build systems know to install this script, users thus have to go out of
their way to really make it work, which is highly unlikely.

Another source that indicates that this tool can be removed is a
question for how to restore deleted branches on StackOverflow [1]. The
top-voted answer uses git-reflog(1) directly and has received more than
3000 votes to date. While "git-resurrect.sh" is also mentioned, it only
got 16 upvotes, and comments mention the above caveat that users have to
do some manual setup to make it work.

It's thus rather clear that the tool doesn't have a lot or even any
users. Remove it.

[1]: https://stackoverflow.com/questions/3640764/can-i-recover-a-branch-after-its-deletion-in-git

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/contrib/git-resurrect.sh b/contrib/git-resurrect.sh
deleted file mode 100755 (executable)
index d843df3..0000000
--- a/contrib/git-resurrect.sh
+++ /dev/null
@@ -1,181 +0,0 @@
-#!/bin/sh
-
-USAGE="[-a] [-r] [-m] [-t] [-n] [-b <newname>] <name>"
-LONG_USAGE="git-resurrect attempts to find traces of a branch tip
-called <name>, and tries to resurrect it.  Currently, the reflog is
-searched for checkout messages, and with -r also merge messages.  With
--m and -t, the history of all refs is scanned for Merge <name> into
-other/Merge <other> into <name> (respectively) commit subjects, which
-is rather slow but allows you to resurrect other people's topic
-branches."
-
-OPTIONS_KEEPDASHDASH=
-OPTIONS_STUCKLONG=
-OPTIONS_SPEC="\
-git resurrect $USAGE
---
-b,branch=            save branch as <newname> instead of <name>
-a,all                same as -l -r -m -t
-k,keep-going         full rev-list scan (instead of first match)
-l,reflog             scan reflog for checkouts (enabled by default)
-r,reflog-merges      scan for merges recorded in reflog
-m,merges             scan for merges into other branches (slow)
-t,merge-targets      scan for merges of other branches into <name>
-n,dry-run            don't recreate the branch"
-
-. git-sh-setup
-
-search_reflog () {
-       sed -ne 's~^\([^ ]*\) .*        checkout: moving from '"$1"' .*~\1~p' \
-               < "$GIT_DIR"/logs/HEAD
-}
-
-search_reflog_merges () {
-       git rev-parse $(
-               sed -ne 's~^[^ ]* \([^ ]*\) .*  merge '"$1"':.*~\1^2~p' \
-                       < "$GIT_DIR"/logs/HEAD
-       )
-}
-
-oid_pattern=$(git hash-object --stdin </dev/null | sed -e 's/./[0-9a-f]/g')
-
-search_merges () {
-       git rev-list --all --grep="Merge branch '$1'" \
-               --pretty=tformat:"%P %s" |
-       sed -ne "/^$oid_pattern \($oid_pattern\) Merge .*/ {s//\1/p;$early_exit}"
-}
-
-search_merge_targets () {
-       git rev-list --all --grep="Merge branch '[^']*' into $branch\$" \
-               --pretty=tformat:"%H %s" --all |
-       sed -ne "/^\($oid_pattern\) Merge .*/ {s//\1/p;$early_exit} "
-}
-
-dry_run=
-early_exit=q
-scan_reflog=t
-scan_reflog_merges=
-scan_merges=
-scan_merge_targets=
-new_name=
-
-while test "$#" != 0; do
-       case "$1" in
-           -b|--branch)
-               shift
-               new_name="$1"
-               ;;
-           -n|--dry-run)
-               dry_run=t
-               ;;
-           --no-dry-run)
-               dry_run=
-               ;;
-           -k|--keep-going)
-               early_exit=
-               ;;
-           --no-keep-going)
-               early_exit=q
-               ;;
-           -m|--merges)
-               scan_merges=t
-               ;;
-           --no-merges)
-               scan_merges=
-               ;;
-           -l|--reflog)
-               scan_reflog=t
-               ;;
-           --no-reflog)
-               scan_reflog=
-               ;;
-           -r|--reflog_merges)
-               scan_reflog_merges=t
-               ;;
-           --no-reflog_merges)
-               scan_reflog_merges=
-               ;;
-           -t|--merge-targets)
-               scan_merge_targets=t
-               ;;
-           --no-merge-targets)
-               scan_merge_targets=
-               ;;
-           -a|--all)
-               scan_reflog=t
-               scan_reflog_merges=t
-               scan_merges=t
-               scan_merge_targets=t
-               ;;
-           --)
-               shift
-               break
-               ;;
-           *)
-               usage
-               ;;
-       esac
-       shift
-done
-
-test "$#" = 1 || usage
-
-all_strategies="$scan_reflog$scan_reflog_merges$scan_merges$scan_merge_targets"
-if test -z "$all_strategies"; then
-       die "must enable at least one of -lrmt"
-fi
-
-branch="$1"
-test -z "$new_name" && new_name="$branch"
-
-if test ! -z "$scan_reflog"; then
-       if test -r "$GIT_DIR"/logs/HEAD; then
-               candidates="$(search_reflog $branch)"
-       else
-               die 'reflog scanning requested, but' \
-                       '$GIT_DIR/logs/HEAD not readable'
-       fi
-fi
-if test ! -z "$scan_reflog_merges"; then
-       if test -r "$GIT_DIR"/logs/HEAD; then
-               candidates="$candidates $(search_reflog_merges $branch)"
-       else
-               die 'reflog scanning requested, but' \
-                       '$GIT_DIR/logs/HEAD not readable'
-       fi
-fi
-if test ! -z "$scan_merges"; then
-       candidates="$candidates $(search_merges $branch)"
-fi
-if test ! -z "$scan_merge_targets"; then
-       candidates="$candidates $(search_merge_targets $branch)"
-fi
-
-candidates="$(git rev-parse $candidates | sort -u)"
-
-if test -z "$candidates"; then
-       hint=
-       test "z$all_strategies" != "ztttt" \
-               && hint=" (maybe try again with -a)"
-       die "no candidates for $branch found$hint"
-fi
-
-echo "** Candidates for $branch **"
-for cmt in $candidates; do
-       git --no-pager log --pretty=tformat:"%ct:%h [%cr] %s" --abbrev-commit -1 $cmt
-done \
-| sort -n | cut -d: -f2-
-
-newest="$(git rev-list -1 $candidates)"
-if test ! -z "$dry_run"; then
-       printf "** Most recent: "
-       git --no-pager log -1 --pretty=tformat:"%h %s" $newest
-elif ! git rev-parse --verify --quiet $new_name >/dev/null; then
-       printf "** Restoring $new_name to "
-       git --no-pager log -1 --pretty=tformat:"%h %s" $newest
-       git branch $new_name $newest
-else
-       printf "Most recent: "
-       git --no-pager log -1 --pretty=tformat:"%h %s" $newest
-       echo "** $new_name already exists, doing nothing"
-fi