Merge branch 'ee/clean-test-fixes' into maint
[git] / builtin / checkout.c
1 #include "builtin.h"
2 #include "lockfile.h"
3 #include "parse-options.h"
4 #include "refs.h"
5 #include "commit.h"
6 #include "tree.h"
7 #include "tree-walk.h"
8 #include "cache-tree.h"
9 #include "unpack-trees.h"
10 #include "dir.h"
11 #include "run-command.h"
12 #include "merge-recursive.h"
13 #include "branch.h"
14 #include "diff.h"
15 #include "revision.h"
16 #include "remote.h"
17 #include "blob.h"
18 #include "xdiff-interface.h"
19 #include "ll-merge.h"
20 #include "resolve-undo.h"
21 #include "submodule.h"
22
23 static const char * const checkout_usage[] = {
24         N_("git checkout [<options>] <branch>"),
25         N_("git checkout [<options>] [<branch>] -- <file>..."),
26         NULL,
27 };
28
29 struct checkout_opts {
30         int patch_mode;
31         int quiet;
32         int merge;
33         int force;
34         int force_detach;
35         int writeout_stage;
36         int overwrite_ignore;
37         int ignore_skipworktree;
38         int ignore_other_worktrees;
39
40         const char *new_branch;
41         const char *new_branch_force;
42         const char *new_orphan_branch;
43         int new_branch_log;
44         enum branch_track track;
45         struct diff_options diff_options;
46
47         int branch_exists;
48         const char *prefix;
49         struct pathspec pathspec;
50         struct tree *source_tree;
51
52         int new_worktree_mode;
53 };
54
55 static int post_checkout_hook(struct commit *old, struct commit *new,
56                               int changed)
57 {
58         return run_hook_le(NULL, "post-checkout",
59                            sha1_to_hex(old ? old->object.sha1 : null_sha1),
60                            sha1_to_hex(new ? new->object.sha1 : null_sha1),
61                            changed ? "1" : "0", NULL);
62         /* "new" can be NULL when checking out from the index before
63            a commit exists. */
64
65 }
66
67 static int update_some(const unsigned char *sha1, struct strbuf *base,
68                 const char *pathname, unsigned mode, int stage, void *context)
69 {
70         int len;
71         struct cache_entry *ce;
72         int pos;
73
74         if (S_ISDIR(mode))
75                 return READ_TREE_RECURSIVE;
76
77         len = base->len + strlen(pathname);
78         ce = xcalloc(1, cache_entry_size(len));
79         hashcpy(ce->sha1, sha1);
80         memcpy(ce->name, base->buf, base->len);
81         memcpy(ce->name + base->len, pathname, len - base->len);
82         ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
83         ce->ce_namelen = len;
84         ce->ce_mode = create_ce_mode(mode);
85
86         /*
87          * If the entry is the same as the current index, we can leave the old
88          * entry in place. Whether it is UPTODATE or not, checkout_entry will
89          * do the right thing.
90          */
91         pos = cache_name_pos(ce->name, ce->ce_namelen);
92         if (pos >= 0) {
93                 struct cache_entry *old = active_cache[pos];
94                 if (ce->ce_mode == old->ce_mode &&
95                     !hashcmp(ce->sha1, old->sha1)) {
96                         old->ce_flags |= CE_UPDATE;
97                         free(ce);
98                         return 0;
99                 }
100         }
101
102         add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
103         return 0;
104 }
105
106 static int read_tree_some(struct tree *tree, const struct pathspec *pathspec)
107 {
108         read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
109
110         /* update the index with the given tree's info
111          * for all args, expanding wildcards, and exit
112          * with any non-zero return code.
113          */
114         return 0;
115 }
116
117 static int skip_same_name(const struct cache_entry *ce, int pos)
118 {
119         while (++pos < active_nr &&
120                !strcmp(active_cache[pos]->name, ce->name))
121                 ; /* skip */
122         return pos;
123 }
124
125 static int check_stage(int stage, const struct cache_entry *ce, int pos)
126 {
127         while (pos < active_nr &&
128                !strcmp(active_cache[pos]->name, ce->name)) {
129                 if (ce_stage(active_cache[pos]) == stage)
130                         return 0;
131                 pos++;
132         }
133         if (stage == 2)
134                 return error(_("path '%s' does not have our version"), ce->name);
135         else
136                 return error(_("path '%s' does not have their version"), ce->name);
137 }
138
139 static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
140 {
141         unsigned seen = 0;
142         const char *name = ce->name;
143
144         while (pos < active_nr) {
145                 ce = active_cache[pos];
146                 if (strcmp(name, ce->name))
147                         break;
148                 seen |= (1 << ce_stage(ce));
149                 pos++;
150         }
151         if ((stages & seen) != stages)
152                 return error(_("path '%s' does not have all necessary versions"),
153                              name);
154         return 0;
155 }
156
157 static int checkout_stage(int stage, struct cache_entry *ce, int pos,
158                           struct checkout *state)
159 {
160         while (pos < active_nr &&
161                !strcmp(active_cache[pos]->name, ce->name)) {
162                 if (ce_stage(active_cache[pos]) == stage)
163                         return checkout_entry(active_cache[pos], state, NULL);
164                 pos++;
165         }
166         if (stage == 2)
167                 return error(_("path '%s' does not have our version"), ce->name);
168         else
169                 return error(_("path '%s' does not have their version"), ce->name);
170 }
171
172 static int checkout_merged(int pos, struct checkout *state)
173 {
174         struct cache_entry *ce = active_cache[pos];
175         const char *path = ce->name;
176         mmfile_t ancestor, ours, theirs;
177         int status;
178         unsigned char sha1[20];
179         mmbuffer_t result_buf;
180         unsigned char threeway[3][20];
181         unsigned mode = 0;
182
183         memset(threeway, 0, sizeof(threeway));
184         while (pos < active_nr) {
185                 int stage;
186                 stage = ce_stage(ce);
187                 if (!stage || strcmp(path, ce->name))
188                         break;
189                 hashcpy(threeway[stage - 1], ce->sha1);
190                 if (stage == 2)
191                         mode = create_ce_mode(ce->ce_mode);
192                 pos++;
193                 ce = active_cache[pos];
194         }
195         if (is_null_sha1(threeway[1]) || is_null_sha1(threeway[2]))
196                 return error(_("path '%s' does not have necessary versions"), path);
197
198         read_mmblob(&ancestor, threeway[0]);
199         read_mmblob(&ours, threeway[1]);
200         read_mmblob(&theirs, threeway[2]);
201
202         /*
203          * NEEDSWORK: re-create conflicts from merges with
204          * merge.renormalize set, too
205          */
206         status = ll_merge(&result_buf, path, &ancestor, "base",
207                           &ours, "ours", &theirs, "theirs", NULL);
208         free(ancestor.ptr);
209         free(ours.ptr);
210         free(theirs.ptr);
211         if (status < 0 || !result_buf.ptr) {
212                 free(result_buf.ptr);
213                 return error(_("path '%s': cannot merge"), path);
214         }
215
216         /*
217          * NEEDSWORK:
218          * There is absolutely no reason to write this as a blob object
219          * and create a phony cache entry just to leak.  This hack is
220          * primarily to get to the write_entry() machinery that massages
221          * the contents to work-tree format and writes out which only
222          * allows it for a cache entry.  The code in write_entry() needs
223          * to be refactored to allow us to feed a <buffer, size, mode>
224          * instead of a cache entry.  Such a refactoring would help
225          * merge_recursive as well (it also writes the merge result to the
226          * object database even when it may contain conflicts).
227          */
228         if (write_sha1_file(result_buf.ptr, result_buf.size,
229                             blob_type, sha1))
230                 die(_("Unable to add merge result for '%s'"), path);
231         ce = make_cache_entry(mode, sha1, path, 2, 0);
232         if (!ce)
233                 die(_("make_cache_entry failed for path '%s'"), path);
234         status = checkout_entry(ce, state, NULL);
235         return status;
236 }
237
238 static int checkout_paths(const struct checkout_opts *opts,
239                           const char *revision)
240 {
241         int pos;
242         struct checkout state;
243         static char *ps_matched;
244         unsigned char rev[20];
245         int flag;
246         struct commit *head;
247         int errs = 0;
248         struct lock_file *lock_file;
249
250         if (opts->track != BRANCH_TRACK_UNSPECIFIED)
251                 die(_("'%s' cannot be used with updating paths"), "--track");
252
253         if (opts->new_branch_log)
254                 die(_("'%s' cannot be used with updating paths"), "-l");
255
256         if (opts->force && opts->patch_mode)
257                 die(_("'%s' cannot be used with updating paths"), "-f");
258
259         if (opts->force_detach)
260                 die(_("'%s' cannot be used with updating paths"), "--detach");
261
262         if (opts->merge && opts->patch_mode)
263                 die(_("'%s' cannot be used with %s"), "--merge", "--patch");
264
265         if (opts->force && opts->merge)
266                 die(_("'%s' cannot be used with %s"), "-f", "-m");
267
268         if (opts->new_branch)
269                 die(_("Cannot update paths and switch to branch '%s' at the same time."),
270                     opts->new_branch);
271
272         if (opts->patch_mode)
273                 return run_add_interactive(revision, "--patch=checkout",
274                                            &opts->pathspec);
275
276         lock_file = xcalloc(1, sizeof(struct lock_file));
277
278         hold_locked_index(lock_file, 1);
279         if (read_cache_preload(&opts->pathspec) < 0)
280                 return error(_("corrupt index file"));
281
282         if (opts->source_tree)
283                 read_tree_some(opts->source_tree, &opts->pathspec);
284
285         ps_matched = xcalloc(opts->pathspec.nr, 1);
286
287         /*
288          * Make sure all pathspecs participated in locating the paths
289          * to be checked out.
290          */
291         for (pos = 0; pos < active_nr; pos++) {
292                 struct cache_entry *ce = active_cache[pos];
293                 ce->ce_flags &= ~CE_MATCHED;
294                 if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
295                         continue;
296                 if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
297                         /*
298                          * "git checkout tree-ish -- path", but this entry
299                          * is in the original index; it will not be checked
300                          * out to the working tree and it does not matter
301                          * if pathspec matched this entry.  We will not do
302                          * anything to this entry at all.
303                          */
304                         continue;
305                 /*
306                  * Either this entry came from the tree-ish we are
307                  * checking the paths out of, or we are checking out
308                  * of the index.
309                  *
310                  * If it comes from the tree-ish, we already know it
311                  * matches the pathspec and could just stamp
312                  * CE_MATCHED to it from update_some(). But we still
313                  * need ps_matched and read_tree_recursive (and
314                  * eventually tree_entry_interesting) cannot fill
315                  * ps_matched yet. Once it can, we can avoid calling
316                  * match_pathspec() for _all_ entries when
317                  * opts->source_tree != NULL.
318                  */
319                 if (ce_path_match(ce, &opts->pathspec, ps_matched))
320                         ce->ce_flags |= CE_MATCHED;
321         }
322
323         if (report_path_error(ps_matched, &opts->pathspec, opts->prefix)) {
324                 free(ps_matched);
325                 return 1;
326         }
327         free(ps_matched);
328
329         /* "checkout -m path" to recreate conflicted state */
330         if (opts->merge)
331                 unmerge_marked_index(&the_index);
332
333         /* Any unmerged paths? */
334         for (pos = 0; pos < active_nr; pos++) {
335                 const struct cache_entry *ce = active_cache[pos];
336                 if (ce->ce_flags & CE_MATCHED) {
337                         if (!ce_stage(ce))
338                                 continue;
339                         if (opts->force) {
340                                 warning(_("path '%s' is unmerged"), ce->name);
341                         } else if (opts->writeout_stage) {
342                                 errs |= check_stage(opts->writeout_stage, ce, pos);
343                         } else if (opts->merge) {
344                                 errs |= check_stages((1<<2) | (1<<3), ce, pos);
345                         } else {
346                                 errs = 1;
347                                 error(_("path '%s' is unmerged"), ce->name);
348                         }
349                         pos = skip_same_name(ce, pos) - 1;
350                 }
351         }
352         if (errs)
353                 return 1;
354
355         /* Now we are committed to check them out */
356         memset(&state, 0, sizeof(state));
357         state.force = 1;
358         state.refresh_cache = 1;
359         state.istate = &the_index;
360         for (pos = 0; pos < active_nr; pos++) {
361                 struct cache_entry *ce = active_cache[pos];
362                 if (ce->ce_flags & CE_MATCHED) {
363                         if (!ce_stage(ce)) {
364                                 errs |= checkout_entry(ce, &state, NULL);
365                                 continue;
366                         }
367                         if (opts->writeout_stage)
368                                 errs |= checkout_stage(opts->writeout_stage, ce, pos, &state);
369                         else if (opts->merge)
370                                 errs |= checkout_merged(pos, &state);
371                         pos = skip_same_name(ce, pos) - 1;
372                 }
373         }
374
375         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
376                 die(_("unable to write new index file"));
377
378         read_ref_full("HEAD", 0, rev, &flag);
379         head = lookup_commit_reference_gently(rev, 1);
380
381         errs |= post_checkout_hook(head, head, 0);
382         return errs;
383 }
384
385 static void show_local_changes(struct object *head,
386                                const struct diff_options *opts)
387 {
388         struct rev_info rev;
389         /* I think we want full paths, even if we're in a subdirectory. */
390         init_revisions(&rev, NULL);
391         rev.diffopt.flags = opts->flags;
392         rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
393         diff_setup_done(&rev.diffopt);
394         add_pending_object(&rev, head, NULL);
395         run_diff_index(&rev, 0);
396 }
397
398 static void describe_detached_head(const char *msg, struct commit *commit)
399 {
400         struct strbuf sb = STRBUF_INIT;
401         if (!parse_commit(commit))
402                 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
403         fprintf(stderr, "%s %s... %s\n", msg,
404                 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
405         strbuf_release(&sb);
406 }
407
408 static int reset_tree(struct tree *tree, const struct checkout_opts *o,
409                       int worktree, int *writeout_error)
410 {
411         struct unpack_trees_options opts;
412         struct tree_desc tree_desc;
413
414         memset(&opts, 0, sizeof(opts));
415         opts.head_idx = -1;
416         opts.update = worktree;
417         opts.skip_unmerged = !worktree;
418         opts.reset = 1;
419         opts.merge = 1;
420         opts.fn = oneway_merge;
421         opts.verbose_update = !o->quiet && isatty(2);
422         opts.src_index = &the_index;
423         opts.dst_index = &the_index;
424         parse_tree(tree);
425         init_tree_desc(&tree_desc, tree->buffer, tree->size);
426         switch (unpack_trees(1, &tree_desc, &opts)) {
427         case -2:
428                 *writeout_error = 1;
429                 /*
430                  * We return 0 nevertheless, as the index is all right
431                  * and more importantly we have made best efforts to
432                  * update paths in the work tree, and we cannot revert
433                  * them.
434                  */
435         case 0:
436                 return 0;
437         default:
438                 return 128;
439         }
440 }
441
442 struct branch_info {
443         const char *name; /* The short name used */
444         const char *path; /* The full name of a real branch */
445         struct commit *commit; /* The named commit */
446         /*
447          * if not null the branch is detached because it's already
448          * checked out in this checkout
449          */
450         char *checkout;
451 };
452
453 static void setup_branch_path(struct branch_info *branch)
454 {
455         struct strbuf buf = STRBUF_INIT;
456
457         strbuf_branchname(&buf, branch->name);
458         if (strcmp(buf.buf, branch->name))
459                 branch->name = xstrdup(buf.buf);
460         strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
461         branch->path = strbuf_detach(&buf, NULL);
462 }
463
464 static int merge_working_tree(const struct checkout_opts *opts,
465                               struct branch_info *old,
466                               struct branch_info *new,
467                               int *writeout_error)
468 {
469         int ret;
470         struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
471
472         hold_locked_index(lock_file, 1);
473         if (read_cache_preload(NULL) < 0)
474                 return error(_("corrupt index file"));
475
476         resolve_undo_clear();
477         if (opts->force) {
478                 ret = reset_tree(new->commit->tree, opts, 1, writeout_error);
479                 if (ret)
480                         return ret;
481         } else {
482                 struct tree_desc trees[2];
483                 struct tree *tree;
484                 struct unpack_trees_options topts;
485
486                 memset(&topts, 0, sizeof(topts));
487                 topts.head_idx = -1;
488                 topts.src_index = &the_index;
489                 topts.dst_index = &the_index;
490
491                 setup_unpack_trees_porcelain(&topts, "checkout");
492
493                 refresh_cache(REFRESH_QUIET);
494
495                 if (unmerged_cache()) {
496                         error(_("you need to resolve your current index first"));
497                         return 1;
498                 }
499
500                 /* 2-way merge to the new branch */
501                 topts.initial_checkout = is_cache_unborn();
502                 topts.update = 1;
503                 topts.merge = 1;
504                 topts.gently = opts->merge && old->commit;
505                 topts.verbose_update = !opts->quiet && isatty(2);
506                 topts.fn = twoway_merge;
507                 if (opts->overwrite_ignore) {
508                         topts.dir = xcalloc(1, sizeof(*topts.dir));
509                         topts.dir->flags |= DIR_SHOW_IGNORED;
510                         setup_standard_excludes(topts.dir);
511                 }
512                 tree = parse_tree_indirect(old->commit && !opts->new_worktree_mode ?
513                                            old->commit->object.sha1 :
514                                            EMPTY_TREE_SHA1_BIN);
515                 init_tree_desc(&trees[0], tree->buffer, tree->size);
516                 tree = parse_tree_indirect(new->commit->object.sha1);
517                 init_tree_desc(&trees[1], tree->buffer, tree->size);
518
519                 ret = unpack_trees(2, trees, &topts);
520                 if (ret == -1) {
521                         /*
522                          * Unpack couldn't do a trivial merge; either
523                          * give up or do a real merge, depending on
524                          * whether the merge flag was used.
525                          */
526                         struct tree *result;
527                         struct tree *work;
528                         struct merge_options o;
529                         if (!opts->merge)
530                                 return 1;
531
532                         /*
533                          * Without old->commit, the below is the same as
534                          * the two-tree unpack we already tried and failed.
535                          */
536                         if (!old->commit)
537                                 return 1;
538
539                         /* Do more real merge */
540
541                         /*
542                          * We update the index fully, then write the
543                          * tree from the index, then merge the new
544                          * branch with the current tree, with the old
545                          * branch as the base. Then we reset the index
546                          * (but not the working tree) to the new
547                          * branch, leaving the working tree as the
548                          * merged version, but skipping unmerged
549                          * entries in the index.
550                          */
551
552                         add_files_to_cache(NULL, NULL, 0);
553                         /*
554                          * NEEDSWORK: carrying over local changes
555                          * when branches have different end-of-line
556                          * normalization (or clean+smudge rules) is
557                          * a pain; plumb in an option to set
558                          * o.renormalize?
559                          */
560                         init_merge_options(&o);
561                         o.verbosity = 0;
562                         work = write_tree_from_memory(&o);
563
564                         ret = reset_tree(new->commit->tree, opts, 1,
565                                          writeout_error);
566                         if (ret)
567                                 return ret;
568                         o.ancestor = old->name;
569                         o.branch1 = new->name;
570                         o.branch2 = "local";
571                         merge_trees(&o, new->commit->tree, work,
572                                 old->commit->tree, &result);
573                         ret = reset_tree(new->commit->tree, opts, 0,
574                                          writeout_error);
575                         if (ret)
576                                 return ret;
577                 }
578         }
579
580         if (!active_cache_tree)
581                 active_cache_tree = cache_tree();
582
583         if (!cache_tree_fully_valid(active_cache_tree))
584                 cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
585
586         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
587                 die(_("unable to write new index file"));
588
589         if (!opts->force && !opts->quiet)
590                 show_local_changes(&new->commit->object, &opts->diff_options);
591
592         return 0;
593 }
594
595 static void report_tracking(struct branch_info *new)
596 {
597         struct strbuf sb = STRBUF_INIT;
598         struct branch *branch = branch_get(new->name);
599
600         if (!format_tracking_info(branch, &sb))
601                 return;
602         fputs(sb.buf, stdout);
603         strbuf_release(&sb);
604 }
605
606 static void update_refs_for_switch(const struct checkout_opts *opts,
607                                    struct branch_info *old,
608                                    struct branch_info *new)
609 {
610         struct strbuf msg = STRBUF_INIT;
611         const char *old_desc, *reflog_msg;
612         if (opts->new_branch) {
613                 if (opts->new_orphan_branch) {
614                         if (opts->new_branch_log && !log_all_ref_updates) {
615                                 int temp;
616                                 struct strbuf log_file = STRBUF_INIT;
617                                 int ret;
618                                 const char *ref_name;
619
620                                 ref_name = mkpath("refs/heads/%s", opts->new_orphan_branch);
621                                 temp = log_all_ref_updates;
622                                 log_all_ref_updates = 1;
623                                 ret = log_ref_setup(ref_name, &log_file);
624                                 log_all_ref_updates = temp;
625                                 strbuf_release(&log_file);
626                                 if (ret) {
627                                         fprintf(stderr, _("Can not do reflog for '%s'\n"),
628                                             opts->new_orphan_branch);
629                                         return;
630                                 }
631                         }
632                 }
633                 else
634                         create_branch(old->name, opts->new_branch, new->name,
635                                       opts->new_branch_force ? 1 : 0,
636                                       opts->new_branch_log,
637                                       opts->new_branch_force ? 1 : 0,
638                                       opts->quiet,
639                                       opts->track);
640                 new->name = opts->new_branch;
641                 setup_branch_path(new);
642         }
643
644         old_desc = old->name;
645         if (!old_desc && old->commit)
646                 old_desc = sha1_to_hex(old->commit->object.sha1);
647
648         reflog_msg = getenv("GIT_REFLOG_ACTION");
649         if (!reflog_msg)
650                 strbuf_addf(&msg, "checkout: moving from %s to %s",
651                         old_desc ? old_desc : "(invalid)", new->name);
652         else
653                 strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
654
655         if (!strcmp(new->name, "HEAD") && !new->path && !opts->force_detach) {
656                 /* Nothing to do. */
657         } else if (opts->force_detach || !new->path) {  /* No longer on any branch. */
658                 update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
659                            REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
660                 if (!opts->quiet) {
661                         if (old->path && advice_detached_head)
662                                 detach_advice(new->name);
663                         describe_detached_head(_("HEAD is now at"), new->commit);
664                 }
665         } else if (new->path) { /* Switch branches. */
666                 create_symref("HEAD", new->path, msg.buf);
667                 if (!opts->quiet) {
668                         if (old->path && !strcmp(new->path, old->path)) {
669                                 if (opts->new_branch_force)
670                                         fprintf(stderr, _("Reset branch '%s'\n"),
671                                                 new->name);
672                                 else
673                                         fprintf(stderr, _("Already on '%s'\n"),
674                                                 new->name);
675                         } else if (opts->new_branch) {
676                                 if (opts->branch_exists)
677                                         fprintf(stderr, _("Switched to and reset branch '%s'\n"), new->name);
678                                 else
679                                         fprintf(stderr, _("Switched to a new branch '%s'\n"), new->name);
680                         } else {
681                                 fprintf(stderr, _("Switched to branch '%s'\n"),
682                                         new->name);
683                         }
684                 }
685                 if (old->path && old->name) {
686                         if (!ref_exists(old->path) && reflog_exists(old->path))
687                                 delete_reflog(old->path);
688                 }
689         }
690         remove_branch_state();
691         strbuf_release(&msg);
692         if (!opts->quiet &&
693             (new->path || (!opts->force_detach && !strcmp(new->name, "HEAD"))))
694                 report_tracking(new);
695 }
696
697 static int add_pending_uninteresting_ref(const char *refname,
698                                          const struct object_id *oid,
699                                          int flags, void *cb_data)
700 {
701         add_pending_sha1(cb_data, refname, oid->hash, UNINTERESTING);
702         return 0;
703 }
704
705 static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
706 {
707         strbuf_addstr(sb, "  ");
708         strbuf_addstr(sb,
709                 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
710         strbuf_addch(sb, ' ');
711         if (!parse_commit(commit))
712                 pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
713         strbuf_addch(sb, '\n');
714 }
715
716 #define ORPHAN_CUTOFF 4
717 static void suggest_reattach(struct commit *commit, struct rev_info *revs)
718 {
719         struct commit *c, *last = NULL;
720         struct strbuf sb = STRBUF_INIT;
721         int lost = 0;
722         while ((c = get_revision(revs)) != NULL) {
723                 if (lost < ORPHAN_CUTOFF)
724                         describe_one_orphan(&sb, c);
725                 last = c;
726                 lost++;
727         }
728         if (ORPHAN_CUTOFF < lost) {
729                 int more = lost - ORPHAN_CUTOFF;
730                 if (more == 1)
731                         describe_one_orphan(&sb, last);
732                 else
733                         strbuf_addf(&sb, _(" ... and %d more.\n"), more);
734         }
735
736         fprintf(stderr,
737                 Q_(
738                 /* The singular version */
739                 "Warning: you are leaving %d commit behind, "
740                 "not connected to\n"
741                 "any of your branches:\n\n"
742                 "%s\n",
743                 /* The plural version */
744                 "Warning: you are leaving %d commits behind, "
745                 "not connected to\n"
746                 "any of your branches:\n\n"
747                 "%s\n",
748                 /* Give ngettext() the count */
749                 lost),
750                 lost,
751                 sb.buf);
752         strbuf_release(&sb);
753
754         if (advice_detached_head)
755                 fprintf(stderr,
756                         Q_(
757                         /* The singular version */
758                         "If you want to keep it by creating a new branch, "
759                         "this may be a good time\nto do so with:\n\n"
760                         " git branch <new-branch-name> %s\n\n",
761                         /* The plural version */
762                         "If you want to keep them by creating a new branch, "
763                         "this may be a good time\nto do so with:\n\n"
764                         " git branch <new-branch-name> %s\n\n",
765                         /* Give ngettext() the count */
766                         lost),
767                         find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
768 }
769
770 /*
771  * We are about to leave commit that was at the tip of a detached
772  * HEAD.  If it is not reachable from any ref, this is the last chance
773  * for the user to do so without resorting to reflog.
774  */
775 static void orphaned_commit_warning(struct commit *old, struct commit *new)
776 {
777         struct rev_info revs;
778         struct object *object = &old->object;
779         struct object_array refs;
780
781         init_revisions(&revs, NULL);
782         setup_revisions(0, NULL, &revs, NULL);
783
784         object->flags &= ~UNINTERESTING;
785         add_pending_object(&revs, object, sha1_to_hex(object->sha1));
786
787         for_each_ref(add_pending_uninteresting_ref, &revs);
788         add_pending_sha1(&revs, "HEAD", new->object.sha1, UNINTERESTING);
789
790         refs = revs.pending;
791         revs.leak_pending = 1;
792
793         if (prepare_revision_walk(&revs))
794                 die(_("internal error in revision walk"));
795         if (!(old->object.flags & UNINTERESTING))
796                 suggest_reattach(old, &revs);
797         else
798                 describe_detached_head(_("Previous HEAD position was"), old);
799
800         clear_commit_marks_for_object_array(&refs, ALL_REV_FLAGS);
801         free(refs.objects);
802 }
803
804 static int switch_branches(const struct checkout_opts *opts,
805                            struct branch_info *new)
806 {
807         int ret = 0;
808         struct branch_info old;
809         void *path_to_free;
810         unsigned char rev[20];
811         int flag, writeout_error = 0;
812         memset(&old, 0, sizeof(old));
813         old.path = path_to_free = resolve_refdup("HEAD", 0, rev, &flag);
814         old.commit = lookup_commit_reference_gently(rev, 1);
815         if (!(flag & REF_ISSYMREF))
816                 old.path = NULL;
817
818         if (old.path)
819                 skip_prefix(old.path, "refs/heads/", &old.name);
820
821         if (!new->name) {
822                 new->name = "HEAD";
823                 new->commit = old.commit;
824                 if (!new->commit)
825                         die(_("You are on a branch yet to be born"));
826                 parse_commit_or_die(new->commit);
827         }
828
829         ret = merge_working_tree(opts, &old, new, &writeout_error);
830         if (ret) {
831                 free(path_to_free);
832                 return ret;
833         }
834
835         if (!opts->quiet && !old.path && old.commit &&
836             new->commit != old.commit && !opts->new_worktree_mode)
837                 orphaned_commit_warning(old.commit, new->commit);
838
839         update_refs_for_switch(opts, &old, new);
840
841         ret = post_checkout_hook(old.commit, new->commit, 1);
842         free(path_to_free);
843         return ret || writeout_error;
844 }
845
846 static int git_checkout_config(const char *var, const char *value, void *cb)
847 {
848         if (!strcmp(var, "diff.ignoresubmodules")) {
849                 struct checkout_opts *opts = cb;
850                 handle_ignore_submodules_arg(&opts->diff_options, value);
851                 return 0;
852         }
853
854         if (starts_with(var, "submodule."))
855                 return parse_submodule_config_option(var, value);
856
857         return git_xmerge_config(var, value, NULL);
858 }
859
860 struct tracking_name_data {
861         /* const */ char *src_ref;
862         char *dst_ref;
863         unsigned char *dst_sha1;
864         int unique;
865 };
866
867 static int check_tracking_name(struct remote *remote, void *cb_data)
868 {
869         struct tracking_name_data *cb = cb_data;
870         struct refspec query;
871         memset(&query, 0, sizeof(struct refspec));
872         query.src = cb->src_ref;
873         if (remote_find_tracking(remote, &query) ||
874             get_sha1(query.dst, cb->dst_sha1)) {
875                 free(query.dst);
876                 return 0;
877         }
878         if (cb->dst_ref) {
879                 free(query.dst);
880                 cb->unique = 0;
881                 return 0;
882         }
883         cb->dst_ref = query.dst;
884         return 0;
885 }
886
887 static const char *unique_tracking_name(const char *name, unsigned char *sha1)
888 {
889         struct tracking_name_data cb_data = { NULL, NULL, NULL, 1 };
890         char src_ref[PATH_MAX];
891         snprintf(src_ref, PATH_MAX, "refs/heads/%s", name);
892         cb_data.src_ref = src_ref;
893         cb_data.dst_sha1 = sha1;
894         for_each_remote(check_tracking_name, &cb_data);
895         if (cb_data.unique)
896                 return cb_data.dst_ref;
897         free(cb_data.dst_ref);
898         return NULL;
899 }
900
901 static void check_linked_checkout(struct branch_info *new, const char *id)
902 {
903         struct strbuf sb = STRBUF_INIT;
904         struct strbuf path = STRBUF_INIT;
905         struct strbuf gitdir = STRBUF_INIT;
906         const char *start, *end;
907
908         if (id)
909                 strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
910         else
911                 strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
912
913         if (strbuf_read_file(&sb, path.buf, 0) < 0 ||
914             !skip_prefix(sb.buf, "ref:", &start))
915                 goto done;
916         while (isspace(*start))
917                 start++;
918         end = start;
919         while (*end && !isspace(*end))
920                 end++;
921         if (strncmp(start, new->path, end - start) || new->path[end - start] != '\0')
922                 goto done;
923         if (id) {
924                 strbuf_reset(&path);
925                 strbuf_addf(&path, "%s/worktrees/%s/gitdir", get_git_common_dir(), id);
926                 if (strbuf_read_file(&gitdir, path.buf, 0) <= 0)
927                         goto done;
928                 strbuf_rtrim(&gitdir);
929         } else
930                 strbuf_addstr(&gitdir, get_git_common_dir());
931         die(_("'%s' is already checked out at '%s'"), new->name, gitdir.buf);
932 done:
933         strbuf_release(&path);
934         strbuf_release(&sb);
935         strbuf_release(&gitdir);
936 }
937
938 static void check_linked_checkouts(struct branch_info *new)
939 {
940         struct strbuf path = STRBUF_INIT;
941         DIR *dir;
942         struct dirent *d;
943
944         strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
945         if ((dir = opendir(path.buf)) == NULL) {
946                 strbuf_release(&path);
947                 return;
948         }
949
950         /*
951          * $GIT_COMMON_DIR/HEAD is practically outside
952          * $GIT_DIR so resolve_ref_unsafe() won't work (it
953          * uses git_path). Parse the ref ourselves.
954          */
955         check_linked_checkout(new, NULL);
956
957         while ((d = readdir(dir)) != NULL) {
958                 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
959                         continue;
960                 check_linked_checkout(new, d->d_name);
961         }
962         strbuf_release(&path);
963         closedir(dir);
964 }
965
966 static int parse_branchname_arg(int argc, const char **argv,
967                                 int dwim_new_local_branch_ok,
968                                 struct branch_info *new,
969                                 struct checkout_opts *opts,
970                                 unsigned char rev[20])
971 {
972         struct tree **source_tree = &opts->source_tree;
973         const char **new_branch = &opts->new_branch;
974         int argcount = 0;
975         unsigned char branch_rev[20];
976         const char *arg;
977         int dash_dash_pos;
978         int has_dash_dash = 0;
979         int i;
980
981         /*
982          * case 1: git checkout <ref> -- [<paths>]
983          *
984          *   <ref> must be a valid tree, everything after the '--' must be
985          *   a path.
986          *
987          * case 2: git checkout -- [<paths>]
988          *
989          *   everything after the '--' must be paths.
990          *
991          * case 3: git checkout <something> [--]
992          *
993          *   (a) If <something> is a commit, that is to
994          *       switch to the branch or detach HEAD at it.  As a special case,
995          *       if <something> is A...B (missing A or B means HEAD but you can
996          *       omit at most one side), and if there is a unique merge base
997          *       between A and B, A...B names that merge base.
998          *
999          *   (b) If <something> is _not_ a commit, either "--" is present
1000          *       or <something> is not a path, no -t or -b was given, and
1001          *       and there is a tracking branch whose name is <something>
1002          *       in one and only one remote, then this is a short-hand to
1003          *       fork local <something> from that remote-tracking branch.
1004          *
1005          *   (c) Otherwise, if "--" is present, treat it like case (1).
1006          *
1007          *   (d) Otherwise :
1008          *       - if it's a reference, treat it like case (1)
1009          *       - else if it's a path, treat it like case (2)
1010          *       - else: fail.
1011          *
1012          * case 4: git checkout <something> <paths>
1013          *
1014          *   The first argument must not be ambiguous.
1015          *   - If it's *only* a reference, treat it like case (1).
1016          *   - If it's only a path, treat it like case (2).
1017          *   - else: fail.
1018          *
1019          */
1020         if (!argc)
1021                 return 0;
1022
1023         arg = argv[0];
1024         dash_dash_pos = -1;
1025         for (i = 0; i < argc; i++) {
1026                 if (!strcmp(argv[i], "--")) {
1027                         dash_dash_pos = i;
1028                         break;
1029                 }
1030         }
1031         if (dash_dash_pos == 0)
1032                 return 1; /* case (2) */
1033         else if (dash_dash_pos == 1)
1034                 has_dash_dash = 1; /* case (3) or (1) */
1035         else if (dash_dash_pos >= 2)
1036                 die(_("only one reference expected, %d given."), dash_dash_pos);
1037
1038         if (!strcmp(arg, "-"))
1039                 arg = "@{-1}";
1040
1041         if (get_sha1_mb(arg, rev)) {
1042                 /*
1043                  * Either case (3) or (4), with <something> not being
1044                  * a commit, or an attempt to use case (1) with an
1045                  * invalid ref.
1046                  *
1047                  * It's likely an error, but we need to find out if
1048                  * we should auto-create the branch, case (3).(b).
1049                  */
1050                 int recover_with_dwim = dwim_new_local_branch_ok;
1051
1052                 if (check_filename(NULL, arg) && !has_dash_dash)
1053                         recover_with_dwim = 0;
1054                 /*
1055                  * Accept "git checkout foo" and "git checkout foo --"
1056                  * as candidates for dwim.
1057                  */
1058                 if (!(argc == 1 && !has_dash_dash) &&
1059                     !(argc == 2 && has_dash_dash))
1060                         recover_with_dwim = 0;
1061
1062                 if (recover_with_dwim) {
1063                         const char *remote = unique_tracking_name(arg, rev);
1064                         if (remote) {
1065                                 *new_branch = arg;
1066                                 arg = remote;
1067                                 /* DWIMmed to create local branch, case (3).(b) */
1068                         } else {
1069                                 recover_with_dwim = 0;
1070                         }
1071                 }
1072
1073                 if (!recover_with_dwim) {
1074                         if (has_dash_dash)
1075                                 die(_("invalid reference: %s"), arg);
1076                         return argcount;
1077                 }
1078         }
1079
1080         /* we can't end up being in (2) anymore, eat the argument */
1081         argcount++;
1082         argv++;
1083         argc--;
1084
1085         new->name = arg;
1086         setup_branch_path(new);
1087
1088         if (!check_refname_format(new->path, 0) &&
1089             !read_ref(new->path, branch_rev))
1090                 hashcpy(rev, branch_rev);
1091         else
1092                 new->path = NULL; /* not an existing branch */
1093
1094         new->commit = lookup_commit_reference_gently(rev, 1);
1095         if (!new->commit) {
1096                 /* not a commit */
1097                 *source_tree = parse_tree_indirect(rev);
1098         } else {
1099                 parse_commit_or_die(new->commit);
1100                 *source_tree = new->commit->tree;
1101         }
1102
1103         if (!*source_tree)                   /* case (1): want a tree */
1104                 die(_("reference is not a tree: %s"), arg);
1105         if (!has_dash_dash) {/* case (3).(d) -> (1) */
1106                 /*
1107                  * Do not complain the most common case
1108                  *      git checkout branch
1109                  * even if there happen to be a file called 'branch';
1110                  * it would be extremely annoying.
1111                  */
1112                 if (argc)
1113                         verify_non_filename(NULL, arg);
1114         } else {
1115                 argcount++;
1116                 argv++;
1117                 argc--;
1118         }
1119
1120         return argcount;
1121 }
1122
1123 static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
1124 {
1125         int status;
1126         struct strbuf branch_ref = STRBUF_INIT;
1127
1128         if (!opts->new_branch)
1129                 die(_("You are on a branch yet to be born"));
1130         strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
1131         status = create_symref("HEAD", branch_ref.buf, "checkout -b");
1132         strbuf_release(&branch_ref);
1133         if (!opts->quiet)
1134                 fprintf(stderr, _("Switched to a new branch '%s'\n"),
1135                         opts->new_branch);
1136         return status;
1137 }
1138
1139 static int checkout_branch(struct checkout_opts *opts,
1140                            struct branch_info *new)
1141 {
1142         if (opts->pathspec.nr)
1143                 die(_("paths cannot be used with switching branches"));
1144
1145         if (opts->patch_mode)
1146                 die(_("'%s' cannot be used with switching branches"),
1147                     "--patch");
1148
1149         if (opts->writeout_stage)
1150                 die(_("'%s' cannot be used with switching branches"),
1151                     "--ours/--theirs");
1152
1153         if (opts->force && opts->merge)
1154                 die(_("'%s' cannot be used with '%s'"), "-f", "-m");
1155
1156         if (opts->force_detach && opts->new_branch)
1157                 die(_("'%s' cannot be used with '%s'"),
1158                     "--detach", "-b/-B/--orphan");
1159
1160         if (opts->new_orphan_branch) {
1161                 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1162                         die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
1163         } else if (opts->force_detach) {
1164                 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1165                         die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
1166         } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
1167                 opts->track = git_branch_track;
1168
1169         if (new->name && !new->commit)
1170                 die(_("Cannot switch branch to a non-commit '%s'"),
1171                     new->name);
1172
1173         if (new->path && !opts->force_detach && !opts->new_branch) {
1174                 unsigned char sha1[20];
1175                 int flag;
1176                 char *head_ref = resolve_refdup("HEAD", 0, sha1, &flag);
1177                 if (head_ref &&
1178                     (!(flag & REF_ISSYMREF) || strcmp(head_ref, new->path)) &&
1179                     !opts->ignore_other_worktrees)
1180                         check_linked_checkouts(new);
1181                 free(head_ref);
1182         }
1183
1184         if (!new->commit && opts->new_branch) {
1185                 unsigned char rev[20];
1186                 int flag;
1187
1188                 if (!read_ref_full("HEAD", 0, rev, &flag) &&
1189                     (flag & REF_ISSYMREF) && is_null_sha1(rev))
1190                         return switch_unborn_to_new_branch(opts);
1191         }
1192         return switch_branches(opts, new);
1193 }
1194
1195 int cmd_checkout(int argc, const char **argv, const char *prefix)
1196 {
1197         struct checkout_opts opts;
1198         struct branch_info new;
1199         char *conflict_style = NULL;
1200         int dwim_new_local_branch = 1;
1201         struct option options[] = {
1202                 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
1203                 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
1204                            N_("create and checkout a new branch")),
1205                 OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
1206                            N_("create/reset and checkout a branch")),
1207                 OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
1208                 OPT_BOOL(0, "detach", &opts.force_detach, N_("detach the HEAD at named commit")),
1209                 OPT_SET_INT('t', "track",  &opts.track, N_("set upstream info for new branch"),
1210                         BRANCH_TRACK_EXPLICIT),
1211                 OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
1212                 OPT_SET_INT('2', "ours", &opts.writeout_stage, N_("checkout our version for unmerged files"),
1213                             2),
1214                 OPT_SET_INT('3', "theirs", &opts.writeout_stage, N_("checkout their version for unmerged files"),
1215                             3),
1216                 OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)")),
1217                 OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
1218                 OPT_BOOL(0, "overwrite-ignore", &opts.overwrite_ignore, N_("update ignored files (default)")),
1219                 OPT_STRING(0, "conflict", &conflict_style, N_("style"),
1220                            N_("conflict style (merge or diff3)")),
1221                 OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
1222                 OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
1223                          N_("do not limit pathspecs to sparse entries only")),
1224                 OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
1225                                 N_("second guess 'git checkout <no-such-branch>'")),
1226                 OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
1227                          N_("do not check if another worktree is holding the given ref")),
1228                 OPT_END(),
1229         };
1230
1231         memset(&opts, 0, sizeof(opts));
1232         memset(&new, 0, sizeof(new));
1233         opts.overwrite_ignore = 1;
1234         opts.prefix = prefix;
1235
1236         gitmodules_config();
1237         git_config(git_checkout_config, &opts);
1238
1239         opts.track = BRANCH_TRACK_UNSPECIFIED;
1240
1241         argc = parse_options(argc, argv, prefix, options, checkout_usage,
1242                              PARSE_OPT_KEEP_DASHDASH);
1243
1244         opts.new_worktree_mode = getenv("GIT_CHECKOUT_NEW_WORKTREE") != NULL;
1245
1246         if (conflict_style) {
1247                 opts.merge = 1; /* implied */
1248                 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1249         }
1250
1251         if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
1252                 die(_("-b, -B and --orphan are mutually exclusive"));
1253
1254         /*
1255          * From here on, new_branch will contain the branch to be checked out,
1256          * and new_branch_force and new_orphan_branch will tell us which one of
1257          * -b/-B/--orphan is being used.
1258          */
1259         if (opts.new_branch_force)
1260                 opts.new_branch = opts.new_branch_force;
1261
1262         if (opts.new_orphan_branch)
1263                 opts.new_branch = opts.new_orphan_branch;
1264
1265         /* --track without -b/-B/--orphan should DWIM */
1266         if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
1267                 const char *argv0 = argv[0];
1268                 if (!argc || !strcmp(argv0, "--"))
1269                         die (_("--track needs a branch name"));
1270                 skip_prefix(argv0, "refs/", &argv0);
1271                 skip_prefix(argv0, "remotes/", &argv0);
1272                 argv0 = strchr(argv0, '/');
1273                 if (!argv0 || !argv0[1])
1274                         die (_("Missing branch name; try -b"));
1275                 opts.new_branch = argv0 + 1;
1276         }
1277
1278         /*
1279          * Extract branch name from command line arguments, so
1280          * all that is left is pathspecs.
1281          *
1282          * Handle
1283          *
1284          *  1) git checkout <tree> -- [<paths>]
1285          *  2) git checkout -- [<paths>]
1286          *  3) git checkout <something> [<paths>]
1287          *
1288          * including "last branch" syntax and DWIM-ery for names of
1289          * remote branches, erroring out for invalid or ambiguous cases.
1290          */
1291         if (argc) {
1292                 unsigned char rev[20];
1293                 int dwim_ok =
1294                         !opts.patch_mode &&
1295                         dwim_new_local_branch &&
1296                         opts.track == BRANCH_TRACK_UNSPECIFIED &&
1297                         !opts.new_branch;
1298                 int n = parse_branchname_arg(argc, argv, dwim_ok,
1299                                              &new, &opts, rev);
1300                 argv += n;
1301                 argc -= n;
1302         }
1303
1304         if (argc) {
1305                 parse_pathspec(&opts.pathspec, 0,
1306                                opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
1307                                prefix, argv);
1308
1309                 if (!opts.pathspec.nr)
1310                         die(_("invalid path specification"));
1311
1312                 /*
1313                  * Try to give more helpful suggestion.
1314                  * new_branch && argc > 1 will be caught later.
1315                  */
1316                 if (opts.new_branch && argc == 1)
1317                         die(_("Cannot update paths and switch to branch '%s' at the same time.\n"
1318                               "Did you intend to checkout '%s' which can not be resolved as commit?"),
1319                             opts.new_branch, argv[0]);
1320
1321                 if (opts.force_detach)
1322                         die(_("git checkout: --detach does not take a path argument '%s'"),
1323                             argv[0]);
1324
1325                 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
1326                         die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
1327                               "checking out of the index."));
1328         }
1329
1330         if (opts.new_branch) {
1331                 struct strbuf buf = STRBUF_INIT;
1332
1333                 opts.branch_exists =
1334                         validate_new_branchname(opts.new_branch, &buf,
1335                                                 !!opts.new_branch_force,
1336                                                 !!opts.new_branch_force);
1337
1338                 strbuf_release(&buf);
1339         }
1340
1341         if (opts.patch_mode || opts.pathspec.nr)
1342                 return checkout_paths(&opts, new.name);
1343         else
1344                 return checkout_branch(&opts, &new);
1345 }