Merge branch 'hu/cherry-pick-previous-branch'

Just like "git checkout -" knows to check out and "git merge -"
knows to merge the branch you were previously on, "git cherry-pick"
now understands "git cherry-pick -" to pick from the previous
branch.

* hu/cherry-pick-previous-branch:
cherry-pick: allow "-" as abbreviation of '@{-1}'

diff --combined builtin/revert.c
index 8e87acd12e622957df6bc0a93903898361149f91,e264a151ea99628646374c6f072db1fa4c1ea47c..52c35e75d90dc07f6a80362f200212e314a14ec8
--- 1/builtin/revert.c
--- 2/builtin/revert.c
+++ b/builtin/revert.c
@@@ -54,7 -54,6 +54,7 @@@ static int option_parse_x(const struct 
        return 0;
  }
  
 +LAST_ARG_MUST_BE_NULL
  static void verify_opt_compatible(const char *me, const char *base_opt, ...)
  {
        const char *this_opt;
@@@ -71,19 -70,43 +71,19 @@@
                die(_("%s: %s cannot be used with %s"), me, this_opt, base_opt);
  }
  
 -static void verify_opt_mutually_compatible(const char *me, ...)
 -{
 -      const char *opt1, *opt2 = NULL;
 -      va_list ap;
 -
 -      va_start(ap, me);
 -      while ((opt1 = va_arg(ap, const char *))) {
 -              if (va_arg(ap, int))
 -                      break;
 -      }
 -      if (opt1) {
 -              while ((opt2 = va_arg(ap, const char *))) {
 -                      if (va_arg(ap, int))
 -                              break;
 -              }
 -      }
 -      va_end(ap);
 -
 -      if (opt1 && opt2)
 -              die(_("%s: %s cannot be used with %s"), me, opt1, opt2);
 -}
 -
  static void parse_args(int argc, const char **argv, struct replay_opts *opts)
  {
        const char * const * usage_str = revert_or_cherry_pick_usage(opts);
        const char *me = action_name(opts);
 -      int remove_state = 0;
 -      int contin = 0;
 -      int rollback = 0;
 +      int cmd = 0;
        struct option options[] = {
 -              OPT_BOOLEAN(0, "quit", &remove_state, N_("end revert or cherry-pick sequence")),
 -              OPT_BOOLEAN(0, "continue", &contin, N_("resume revert or cherry-pick sequence")),
 -              OPT_BOOLEAN(0, "abort", &rollback, N_("cancel revert or cherry-pick sequence")),
 -              OPT_BOOLEAN('n', "no-commit", &opts->no_commit, N_("don't automatically commit")),
 -              OPT_BOOLEAN('e', "edit", &opts->edit, N_("edit the commit message")),
 +              OPT_CMDMODE(0, "quit", &cmd, N_("end revert or cherry-pick sequence"), 'q'),
 +              OPT_CMDMODE(0, "continue", &cmd, N_("resume revert or cherry-pick sequence"), 'c'),
 +              OPT_CMDMODE(0, "abort", &cmd, N_("cancel revert or cherry-pick sequence"), 'a'),
 +              OPT_BOOL('n', "no-commit", &opts->no_commit, N_("don't automatically commit")),
 +              OPT_BOOL('e', "edit", &opts->edit, N_("edit the commit message")),
                OPT_NOOP_NOARG('r', NULL),
 -              OPT_BOOLEAN('s', "signoff", &opts->signoff, N_("add Signed-off-by:")),
 +              OPT_BOOL('s', "signoff", &opts->signoff, N_("add Signed-off-by:")),
                OPT_INTEGER('m', "mainline", &opts->mainline, N_("parent number")),
                OPT_RERERE_AUTOUPDATE(&opts->allow_rerere_auto),
                OPT_STRING(0, "strategy", &opts->strategy, N_("strategy"), N_("merge strategy")),
@@@ -99,11 -122,11 +99,11 @@@
  
        if (opts->action == REPLAY_PICK) {
                struct option cp_extra[] = {
 -                      OPT_BOOLEAN('x', NULL, &opts->record_origin, N_("append commit name")),
 -                      OPT_BOOLEAN(0, "ff", &opts->allow_ff, N_("allow fast-forward")),
 -                      OPT_BOOLEAN(0, "allow-empty", &opts->allow_empty, N_("preserve initially empty commits")),
 -                      OPT_BOOLEAN(0, "allow-empty-message", &opts->allow_empty_message, N_("allow commits with empty messages")),
 -                      OPT_BOOLEAN(0, "keep-redundant-commits", &opts->keep_redundant_commits, N_("keep redundant, empty commits")),
 +                      OPT_BOOL('x', NULL, &opts->record_origin, N_("append commit name")),
 +                      OPT_BOOL(0, "ff", &opts->allow_ff, N_("allow fast-forward")),
 +                      OPT_BOOL(0, "allow-empty", &opts->allow_empty, N_("preserve initially empty commits")),
 +                      OPT_BOOL(0, "allow-empty-message", &opts->allow_empty_message, N_("allow commits with empty messages")),
 +                      OPT_BOOL(0, "keep-redundant-commits", &opts->keep_redundant_commits, N_("keep redundant, empty commits")),
                        OPT_END(),
                };
                if (parse_options_concat(options, ARRAY_SIZE(options), cp_extra))
@@@ -114,16 -137,23 +114,16 @@@
                        PARSE_OPT_KEEP_ARGV0 |
                        PARSE_OPT_KEEP_UNKNOWN);
  
 -      /* Check for incompatible subcommands */
 -      verify_opt_mutually_compatible(me,
 -                              "--quit", remove_state,
 -                              "--continue", contin,
 -                              "--abort", rollback,
 -                              NULL);
 -
        /* implies allow_empty */
        if (opts->keep_redundant_commits)
                opts->allow_empty = 1;
  
        /* Set the subcommand */
 -      if (remove_state)
 +      if (cmd == 'q')
                opts->subcommand = REPLAY_REMOVE_STATE;
 -      else if (contin)
 +      else if (cmd == 'c')
                opts->subcommand = REPLAY_CONTINUE;
 -      else if (rollback)
 +      else if (cmd == 'a')
                opts->subcommand = REPLAY_ROLLBACK;
        else
                opts->subcommand = REPLAY_NONE;
@@@ -202,6 -232,8 +202,8 @@@ int cmd_cherry_pick(int argc, const cha
        memset(&opts, 0, sizeof(opts));
        opts.action = REPLAY_PICK;
        git_config(git_default_config, NULL);
+       if (!strcmp(argv[1], "-"))
+               argv[1] = "@{-1}";
        parse_args(argc, argv, &opts);
        res = sequencer_pick_revisions(&opts);
        if (res < 0)

diff --combined t/t3501-revert-cherry-pick.sh
index 46aaf2f511f6d37e8552d0b12fa64f7e30accd1d,6281619141afec8cc2d3a0696bbed4ec91e32b54..bff6ffe08817ed0c057909aa1d3f93140cf6a3e0
--- 1/t/t3501-revert-cherry-pick.sh
--- 2/t/t3501-revert-cherry-pick.sh
+++ b/t/t3501-revert-cherry-pick.sh
@@@ -100,7 -100,7 +100,7 @@@ test_expect_success 'revert forbidden o
  
  '
  
 -test_expect_success 'chery-pick on unborn branch' '
 +test_expect_success 'cherry-pick on unborn branch' '
        git checkout --orphan unborn &&
        git rm --cached -r . &&
        rm -rf * &&
@@@ -109,4 -109,24 +109,24 @@@
        ! test_cmp_rev initial HEAD
  '
  
+ test_expect_success 'cherry-pick "-" to pick from previous branch' '
+       git checkout unborn &&
+       test_commit to-pick actual content &&
+       git checkout master &&
+       git cherry-pick - &&
+       echo content >expect &&
+       test_cmp expect actual
+ '
+ 
+ test_expect_success 'cherry-pick "-" is meaningless without checkout' '
+       test_create_repo afresh &&
+       (
+               cd afresh &&
+               test_commit one &&
+               test_commit two &&
+               test_commit three &&
+               test_must_fail git cherry-pick -
+       )
+ '
+ 
  test_done