tree.c: make read_tree*() take 'struct repository *'
[git/git.git] / builtin / checkout.c
1 #include "builtin.h"
2 #include "config.h"
3 #include "checkout.h"
4 #include "lockfile.h"
5 #include "parse-options.h"
6 #include "refs.h"
7 #include "object-store.h"
8 #include "commit.h"
9 #include "tree.h"
10 #include "tree-walk.h"
11 #include "cache-tree.h"
12 #include "unpack-trees.h"
13 #include "dir.h"
14 #include "run-command.h"
15 #include "merge-recursive.h"
16 #include "branch.h"
17 #include "diff.h"
18 #include "revision.h"
19 #include "remote.h"
20 #include "blob.h"
21 #include "xdiff-interface.h"
22 #include "ll-merge.h"
23 #include "resolve-undo.h"
24 #include "submodule-config.h"
25 #include "submodule.h"
26 #include "advice.h"
27
28 static int checkout_optimize_new_branch;
29
30 static const char * const checkout_usage[] = {
31 N_("git checkout [<options>] <branch>"),
32 N_("git checkout [<options>] [<branch>] -- <file>..."),
33 NULL,
34 };
35
36 struct checkout_opts {
37 int patch_mode;
38 int quiet;
39 int merge;
40 int force;
41 int force_detach;
42 int writeout_stage;
43 int overwrite_ignore;
44 int ignore_skipworktree;
45 int ignore_other_worktrees;
46 int show_progress;
47 /*
48 * If new checkout options are added, skip_merge_working_tree
49 * should be updated accordingly.
50 */
51
52 const char *new_branch;
53 const char *new_branch_force;
54 const char *new_orphan_branch;
55 int new_branch_log;
56 enum branch_track track;
57 struct diff_options diff_options;
58
59 int branch_exists;
60 const char *prefix;
61 struct pathspec pathspec;
62 struct tree *source_tree;
63 };
64
65 static int post_checkout_hook(struct commit *old_commit, struct commit *new_commit,
66 int changed)
67 {
68 return run_hook_le(NULL, "post-checkout",
69 oid_to_hex(old_commit ? &old_commit->object.oid : &null_oid),
70 oid_to_hex(new_commit ? &new_commit->object.oid : &null_oid),
71 changed ? "1" : "0", NULL);
72 /* "new_commit" can be NULL when checking out from the index before
73 a commit exists. */
74
75 }
76
77 static int update_some(const struct object_id *oid, struct strbuf *base,
78 const char *pathname, unsigned mode, int stage, void *context)
79 {
80 int len;
81 struct cache_entry *ce;
82 int pos;
83
84 if (S_ISDIR(mode))
85 return READ_TREE_RECURSIVE;
86
87 len = base->len + strlen(pathname);
88 ce = make_empty_cache_entry(&the_index, len);
89 oidcpy(&ce->oid, oid);
90 memcpy(ce->name, base->buf, base->len);
91 memcpy(ce->name + base->len, pathname, len - base->len);
92 ce->ce_flags = create_ce_flags(0) | CE_UPDATE;
93 ce->ce_namelen = len;
94 ce->ce_mode = create_ce_mode(mode);
95
96 /*
97 * If the entry is the same as the current index, we can leave the old
98 * entry in place. Whether it is UPTODATE or not, checkout_entry will
99 * do the right thing.
100 */
101 pos = cache_name_pos(ce->name, ce->ce_namelen);
102 if (pos >= 0) {
103 struct cache_entry *old = active_cache[pos];
104 if (ce->ce_mode == old->ce_mode &&
105 oideq(&ce->oid, &old->oid)) {
106 old->ce_flags |= CE_UPDATE;
107 discard_cache_entry(ce);
108 return 0;
109 }
110 }
111
112 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
113 return 0;
114 }
115
116 static int read_tree_some(struct tree *tree, const struct pathspec *pathspec)
117 {
118 read_tree_recursive(the_repository, tree, "", 0, 0,
119 pathspec, update_some, NULL);
120
121 /* update the index with the given tree's info
122 * for all args, expanding wildcards, and exit
123 * with any non-zero return code.
124 */
125 return 0;
126 }
127
128 static int skip_same_name(const struct cache_entry *ce, int pos)
129 {
130 while (++pos < active_nr &&
131 !strcmp(active_cache[pos]->name, ce->name))
132 ; /* skip */
133 return pos;
134 }
135
136 static int check_stage(int stage, const struct cache_entry *ce, int pos)
137 {
138 while (pos < active_nr &&
139 !strcmp(active_cache[pos]->name, ce->name)) {
140 if (ce_stage(active_cache[pos]) == stage)
141 return 0;
142 pos++;
143 }
144 if (stage == 2)
145 return error(_("path '%s' does not have our version"), ce->name);
146 else
147 return error(_("path '%s' does not have their version"), ce->name);
148 }
149
150 static int check_stages(unsigned stages, const struct cache_entry *ce, int pos)
151 {
152 unsigned seen = 0;
153 const char *name = ce->name;
154
155 while (pos < active_nr) {
156 ce = active_cache[pos];
157 if (strcmp(name, ce->name))
158 break;
159 seen |= (1 << ce_stage(ce));
160 pos++;
161 }
162 if ((stages & seen) != stages)
163 return error(_("path '%s' does not have all necessary versions"),
164 name);
165 return 0;
166 }
167
168 static int checkout_stage(int stage, const struct cache_entry *ce, int pos,
169 const struct checkout *state)
170 {
171 while (pos < active_nr &&
172 !strcmp(active_cache[pos]->name, ce->name)) {
173 if (ce_stage(active_cache[pos]) == stage)
174 return checkout_entry(active_cache[pos], state, NULL);
175 pos++;
176 }
177 if (stage == 2)
178 return error(_("path '%s' does not have our version"), ce->name);
179 else
180 return error(_("path '%s' does not have their version"), ce->name);
181 }
182
183 static int checkout_merged(int pos, const struct checkout *state)
184 {
185 struct cache_entry *ce = active_cache[pos];
186 const char *path = ce->name;
187 mmfile_t ancestor, ours, theirs;
188 int status;
189 struct object_id oid;
190 mmbuffer_t result_buf;
191 struct object_id threeway[3];
192 unsigned mode = 0;
193
194 memset(threeway, 0, sizeof(threeway));
195 while (pos < active_nr) {
196 int stage;
197 stage = ce_stage(ce);
198 if (!stage || strcmp(path, ce->name))
199 break;
200 oidcpy(&threeway[stage - 1], &ce->oid);
201 if (stage == 2)
202 mode = create_ce_mode(ce->ce_mode);
203 pos++;
204 ce = active_cache[pos];
205 }
206 if (is_null_oid(&threeway[1]) || is_null_oid(&threeway[2]))
207 return error(_("path '%s' does not have necessary versions"), path);
208
209 read_mmblob(&ancestor, &threeway[0]);
210 read_mmblob(&ours, &threeway[1]);
211 read_mmblob(&theirs, &threeway[2]);
212
213 /*
214 * NEEDSWORK: re-create conflicts from merges with
215 * merge.renormalize set, too
216 */
217 status = ll_merge(&result_buf, path, &ancestor, "base",
218 &ours, "ours", &theirs, "theirs",
219 state->istate, NULL);
220 free(ancestor.ptr);
221 free(ours.ptr);
222 free(theirs.ptr);
223 if (status < 0 || !result_buf.ptr) {
224 free(result_buf.ptr);
225 return error(_("path '%s': cannot merge"), path);
226 }
227
228 /*
229 * NEEDSWORK:
230 * There is absolutely no reason to write this as a blob object
231 * and create a phony cache entry. This hack is primarily to get
232 * to the write_entry() machinery that massages the contents to
233 * work-tree format and writes out which only allows it for a
234 * cache entry. The code in write_entry() needs to be refactored
235 * to allow us to feed a <buffer, size, mode> instead of a cache
236 * entry. Such a refactoring would help merge_recursive as well
237 * (it also writes the merge result to the object database even
238 * when it may contain conflicts).
239 */
240 if (write_object_file(result_buf.ptr, result_buf.size, blob_type, &oid))
241 die(_("Unable to add merge result for '%s'"), path);
242 free(result_buf.ptr);
243 ce = make_transient_cache_entry(mode, &oid, path, 2);
244 if (!ce)
245 die(_("make_cache_entry failed for path '%s'"), path);
246 status = checkout_entry(ce, state, NULL);
247 discard_cache_entry(ce);
248 return status;
249 }
250
251 static int checkout_paths(const struct checkout_opts *opts,
252 const char *revision)
253 {
254 int pos;
255 struct checkout state = CHECKOUT_INIT;
256 static char *ps_matched;
257 struct object_id rev;
258 struct commit *head;
259 int errs = 0;
260 struct lock_file lock_file = LOCK_INIT;
261
262 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
263 die(_("'%s' cannot be used with updating paths"), "--track");
264
265 if (opts->new_branch_log)
266 die(_("'%s' cannot be used with updating paths"), "-l");
267
268 if (opts->force && opts->patch_mode)
269 die(_("'%s' cannot be used with updating paths"), "-f");
270
271 if (opts->force_detach)
272 die(_("'%s' cannot be used with updating paths"), "--detach");
273
274 if (opts->merge && opts->patch_mode)
275 die(_("'%s' cannot be used with %s"), "--merge", "--patch");
276
277 if (opts->force && opts->merge)
278 die(_("'%s' cannot be used with %s"), "-f", "-m");
279
280 if (opts->new_branch)
281 die(_("Cannot update paths and switch to branch '%s' at the same time."),
282 opts->new_branch);
283
284 if (opts->patch_mode)
285 return run_add_interactive(revision, "--patch=checkout",
286 &opts->pathspec);
287
288 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
289 if (read_cache_preload(&opts->pathspec) < 0)
290 return error(_("index file corrupt"));
291
292 if (opts->source_tree)
293 read_tree_some(opts->source_tree, &opts->pathspec);
294
295 ps_matched = xcalloc(opts->pathspec.nr, 1);
296
297 /*
298 * Make sure all pathspecs participated in locating the paths
299 * to be checked out.
300 */
301 for (pos = 0; pos < active_nr; pos++) {
302 struct cache_entry *ce = active_cache[pos];
303 ce->ce_flags &= ~CE_MATCHED;
304 if (!opts->ignore_skipworktree && ce_skip_worktree(ce))
305 continue;
306 if (opts->source_tree && !(ce->ce_flags & CE_UPDATE))
307 /*
308 * "git checkout tree-ish -- path", but this entry
309 * is in the original index; it will not be checked
310 * out to the working tree and it does not matter
311 * if pathspec matched this entry. We will not do
312 * anything to this entry at all.
313 */
314 continue;
315 /*
316 * Either this entry came from the tree-ish we are
317 * checking the paths out of, or we are checking out
318 * of the index.
319 *
320 * If it comes from the tree-ish, we already know it
321 * matches the pathspec and could just stamp
322 * CE_MATCHED to it from update_some(). But we still
323 * need ps_matched and read_tree_recursive (and
324 * eventually tree_entry_interesting) cannot fill
325 * ps_matched yet. Once it can, we can avoid calling
326 * match_pathspec() for _all_ entries when
327 * opts->source_tree != NULL.
328 */
329 if (ce_path_match(&the_index, ce, &opts->pathspec, ps_matched))
330 ce->ce_flags |= CE_MATCHED;
331 }
332
333 if (report_path_error(ps_matched, &opts->pathspec, opts->prefix)) {
334 free(ps_matched);
335 return 1;
336 }
337 free(ps_matched);
338
339 /* "checkout -m path" to recreate conflicted state */
340 if (opts->merge)
341 unmerge_marked_index(&the_index);
342
343 /* Any unmerged paths? */
344 for (pos = 0; pos < active_nr; pos++) {
345 const struct cache_entry *ce = active_cache[pos];
346 if (ce->ce_flags & CE_MATCHED) {
347 if (!ce_stage(ce))
348 continue;
349 if (opts->force) {
350 warning(_("path '%s' is unmerged"), ce->name);
351 } else if (opts->writeout_stage) {
352 errs |= check_stage(opts->writeout_stage, ce, pos);
353 } else if (opts->merge) {
354 errs |= check_stages((1<<2) | (1<<3), ce, pos);
355 } else {
356 errs = 1;
357 error(_("path '%s' is unmerged"), ce->name);
358 }
359 pos = skip_same_name(ce, pos) - 1;
360 }
361 }
362 if (errs)
363 return 1;
364
365 /* Now we are committed to check them out */
366 state.force = 1;
367 state.refresh_cache = 1;
368 state.istate = &the_index;
369
370 enable_delayed_checkout(&state);
371 for (pos = 0; pos < active_nr; pos++) {
372 struct cache_entry *ce = active_cache[pos];
373 if (ce->ce_flags & CE_MATCHED) {
374 if (!ce_stage(ce)) {
375 errs |= checkout_entry(ce, &state, NULL);
376 continue;
377 }
378 if (opts->writeout_stage)
379 errs |= checkout_stage(opts->writeout_stage, ce, pos, &state);
380 else if (opts->merge)
381 errs |= checkout_merged(pos, &state);
382 pos = skip_same_name(ce, pos) - 1;
383 }
384 }
385 errs |= finish_delayed_checkout(&state);
386
387 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
388 die(_("unable to write new index file"));
389
390 read_ref_full("HEAD", 0, &rev, NULL);
391 head = lookup_commit_reference_gently(the_repository, &rev, 1);
392
393 errs |= post_checkout_hook(head, head, 0);
394 return errs;
395 }
396
397 static void show_local_changes(struct object *head,
398 const struct diff_options *opts)
399 {
400 struct rev_info rev;
401 /* I think we want full paths, even if we're in a subdirectory. */
402 repo_init_revisions(the_repository, &rev, NULL);
403 rev.diffopt.flags = opts->flags;
404 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
405 diff_setup_done(&rev.diffopt);
406 add_pending_object(&rev, head, NULL);
407 run_diff_index(&rev, 0);
408 }
409
410 static void describe_detached_head(const char *msg, struct commit *commit)
411 {
412 struct strbuf sb = STRBUF_INIT;
413
414 if (!parse_commit(commit))
415 pp_commit_easy(CMIT_FMT_ONELINE, commit, &sb);
416 if (print_sha1_ellipsis()) {
417 fprintf(stderr, "%s %s... %s\n", msg,
418 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV), sb.buf);
419 } else {
420 fprintf(stderr, "%s %s %s\n", msg,
421 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV), sb.buf);
422 }
423 strbuf_release(&sb);
424 }
425
426 static int reset_tree(struct tree *tree, const struct checkout_opts *o,
427 int worktree, int *writeout_error)
428 {
429 struct unpack_trees_options opts;
430 struct tree_desc tree_desc;
431
432 memset(&opts, 0, sizeof(opts));
433 opts.head_idx = -1;
434 opts.update = worktree;
435 opts.skip_unmerged = !worktree;
436 opts.reset = 1;
437 opts.merge = 1;
438 opts.fn = oneway_merge;
439 opts.verbose_update = o->show_progress;
440 opts.src_index = &the_index;
441 opts.dst_index = &the_index;
442 parse_tree(tree);
443 init_tree_desc(&tree_desc, tree->buffer, tree->size);
444 switch (unpack_trees(1, &tree_desc, &opts)) {
445 case -2:
446 *writeout_error = 1;
447 /*
448 * We return 0 nevertheless, as the index is all right
449 * and more importantly we have made best efforts to
450 * update paths in the work tree, and we cannot revert
451 * them.
452 */
453 /* fallthrough */
454 case 0:
455 return 0;
456 default:
457 return 128;
458 }
459 }
460
461 struct branch_info {
462 const char *name; /* The short name used */
463 const char *path; /* The full name of a real branch */
464 struct commit *commit; /* The named commit */
465 /*
466 * if not null the branch is detached because it's already
467 * checked out in this checkout
468 */
469 char *checkout;
470 };
471
472 static void setup_branch_path(struct branch_info *branch)
473 {
474 struct strbuf buf = STRBUF_INIT;
475
476 strbuf_branchname(&buf, branch->name, INTERPRET_BRANCH_LOCAL);
477 if (strcmp(buf.buf, branch->name))
478 branch->name = xstrdup(buf.buf);
479 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
480 branch->path = strbuf_detach(&buf, NULL);
481 }
482
483 /*
484 * Skip merging the trees, updating the index and working directory if and
485 * only if we are creating a new branch via "git checkout -b <new_branch>."
486 */
487 static int skip_merge_working_tree(const struct checkout_opts *opts,
488 const struct branch_info *old_branch_info,
489 const struct branch_info *new_branch_info)
490 {
491 /*
492 * Do the merge if sparse checkout is on and the user has not opted in
493 * to the optimized behavior
494 */
495 if (core_apply_sparse_checkout && !checkout_optimize_new_branch)
496 return 0;
497
498 /*
499 * We must do the merge if we are actually moving to a new commit.
500 */
501 if (!old_branch_info->commit || !new_branch_info->commit ||
502 !oideq(&old_branch_info->commit->object.oid,
503 &new_branch_info->commit->object.oid))
504 return 0;
505
506 /*
507 * opts->patch_mode cannot be used with switching branches so is
508 * not tested here
509 */
510
511 /*
512 * opts->quiet only impacts output so doesn't require a merge
513 */
514
515 /*
516 * Honor the explicit request for a three-way merge or to throw away
517 * local changes
518 */
519 if (opts->merge || opts->force)
520 return 0;
521
522 /*
523 * --detach is documented as "updating the index and the files in the
524 * working tree" but this optimization skips those steps so fall through
525 * to the regular code path.
526 */
527 if (opts->force_detach)
528 return 0;
529
530 /*
531 * opts->writeout_stage cannot be used with switching branches so is
532 * not tested here
533 */
534
535 /*
536 * Honor the explicit ignore requests
537 */
538 if (!opts->overwrite_ignore || opts->ignore_skipworktree ||
539 opts->ignore_other_worktrees)
540 return 0;
541
542 /*
543 * opts->show_progress only impacts output so doesn't require a merge
544 */
545
546 /*
547 * If we aren't creating a new branch any changes or updates will
548 * happen in the existing branch. Since that could only be updating
549 * the index and working directory, we don't want to skip those steps
550 * or we've defeated any purpose in running the command.
551 */
552 if (!opts->new_branch)
553 return 0;
554
555 /*
556 * new_branch_force is defined to "create/reset and checkout a branch"
557 * so needs to go through the merge to do the reset
558 */
559 if (opts->new_branch_force)
560 return 0;
561
562 /*
563 * A new orphaned branch requrires the index and the working tree to be
564 * adjusted to <start_point>
565 */
566 if (opts->new_orphan_branch)
567 return 0;
568
569 /*
570 * Remaining variables are not checkout options but used to track state
571 */
572
573 return 1;
574 }
575
576 static int merge_working_tree(const struct checkout_opts *opts,
577 struct branch_info *old_branch_info,
578 struct branch_info *new_branch_info,
579 int *writeout_error)
580 {
581 int ret;
582 struct lock_file lock_file = LOCK_INIT;
583
584 hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
585 if (read_cache_preload(NULL) < 0)
586 return error(_("index file corrupt"));
587
588 resolve_undo_clear();
589 if (opts->force) {
590 ret = reset_tree(get_commit_tree(new_branch_info->commit),
591 opts, 1, writeout_error);
592 if (ret)
593 return ret;
594 } else {
595 struct tree_desc trees[2];
596 struct tree *tree;
597 struct unpack_trees_options topts;
598
599 memset(&topts, 0, sizeof(topts));
600 topts.head_idx = -1;
601 topts.src_index = &the_index;
602 topts.dst_index = &the_index;
603
604 setup_unpack_trees_porcelain(&topts, "checkout");
605
606 refresh_cache(REFRESH_QUIET);
607
608 if (unmerged_cache()) {
609 error(_("you need to resolve your current index first"));
610 return 1;
611 }
612
613 /* 2-way merge to the new branch */
614 topts.initial_checkout = is_cache_unborn();
615 topts.update = 1;
616 topts.merge = 1;
617 topts.gently = opts->merge && old_branch_info->commit;
618 topts.verbose_update = opts->show_progress;
619 topts.fn = twoway_merge;
620 if (opts->overwrite_ignore) {
621 topts.dir = xcalloc(1, sizeof(*topts.dir));
622 topts.dir->flags |= DIR_SHOW_IGNORED;
623 setup_standard_excludes(topts.dir);
624 }
625 tree = parse_tree_indirect(old_branch_info->commit ?
626 &old_branch_info->commit->object.oid :
627 the_hash_algo->empty_tree);
628 init_tree_desc(&trees[0], tree->buffer, tree->size);
629 tree = parse_tree_indirect(&new_branch_info->commit->object.oid);
630 init_tree_desc(&trees[1], tree->buffer, tree->size);
631
632 ret = unpack_trees(2, trees, &topts);
633 clear_unpack_trees_porcelain(&topts);
634 if (ret == -1) {
635 /*
636 * Unpack couldn't do a trivial merge; either
637 * give up or do a real merge, depending on
638 * whether the merge flag was used.
639 */
640 struct tree *result;
641 struct tree *work;
642 struct merge_options o;
643 if (!opts->merge)
644 return 1;
645
646 /*
647 * Without old_branch_info->commit, the below is the same as
648 * the two-tree unpack we already tried and failed.
649 */
650 if (!old_branch_info->commit)
651 return 1;
652
653 /* Do more real merge */
654
655 /*
656 * We update the index fully, then write the
657 * tree from the index, then merge the new
658 * branch with the current tree, with the old
659 * branch as the base. Then we reset the index
660 * (but not the working tree) to the new
661 * branch, leaving the working tree as the
662 * merged version, but skipping unmerged
663 * entries in the index.
664 */
665
666 add_files_to_cache(NULL, NULL, 0);
667 /*
668 * NEEDSWORK: carrying over local changes
669 * when branches have different end-of-line
670 * normalization (or clean+smudge rules) is
671 * a pain; plumb in an option to set
672 * o.renormalize?
673 */
674 init_merge_options(&o);
675 o.verbosity = 0;
676 work = write_tree_from_memory(&o);
677
678 ret = reset_tree(get_commit_tree(new_branch_info->commit),
679 opts, 1,
680 writeout_error);
681 if (ret)
682 return ret;
683 o.ancestor = old_branch_info->name;
684 o.branch1 = new_branch_info->name;
685 o.branch2 = "local";
686 ret = merge_trees(&o,
687 get_commit_tree(new_branch_info->commit),
688 work,
689 get_commit_tree(old_branch_info->commit),
690 &result);
691 if (ret < 0)
692 exit(128);
693 ret = reset_tree(get_commit_tree(new_branch_info->commit),
694 opts, 0,
695 writeout_error);
696 strbuf_release(&o.obuf);
697 if (ret)
698 return ret;
699 }
700 }
701
702 if (!active_cache_tree)
703 active_cache_tree = cache_tree();
704
705 if (!cache_tree_fully_valid(active_cache_tree))
706 cache_tree_update(&the_index, WRITE_TREE_SILENT | WRITE_TREE_REPAIR);
707
708 if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
709 die(_("unable to write new index file"));
710
711 if (!opts->force && !opts->quiet)
712 show_local_changes(&new_branch_info->commit->object, &opts->diff_options);
713
714 return 0;
715 }
716
717 static void report_tracking(struct branch_info *new_branch_info)
718 {
719 struct strbuf sb = STRBUF_INIT;
720 struct branch *branch = branch_get(new_branch_info->name);
721
722 if (!format_tracking_info(branch, &sb, AHEAD_BEHIND_FULL))
723 return;
724 fputs(sb.buf, stdout);
725 strbuf_release(&sb);
726 }
727
728 static void update_refs_for_switch(const struct checkout_opts *opts,
729 struct branch_info *old_branch_info,
730 struct branch_info *new_branch_info)
731 {
732 struct strbuf msg = STRBUF_INIT;
733 const char *old_desc, *reflog_msg;
734 if (opts->new_branch) {
735 if (opts->new_orphan_branch) {
736 char *refname;
737
738 refname = mkpathdup("refs/heads/%s", opts->new_orphan_branch);
739 if (opts->new_branch_log &&
740 !should_autocreate_reflog(refname)) {
741 int ret;
742 struct strbuf err = STRBUF_INIT;
743
744 ret = safe_create_reflog(refname, 1, &err);
745 if (ret) {
746 fprintf(stderr, _("Can not do reflog for '%s': %s\n"),
747 opts->new_orphan_branch, err.buf);
748 strbuf_release(&err);
749 free(refname);
750 return;
751 }
752 strbuf_release(&err);
753 }
754 free(refname);
755 }
756 else
757 create_branch(opts->new_branch, new_branch_info->name,
758 opts->new_branch_force ? 1 : 0,
759 opts->new_branch_force ? 1 : 0,
760 opts->new_branch_log,
761 opts->quiet,
762 opts->track);
763 new_branch_info->name = opts->new_branch;
764 setup_branch_path(new_branch_info);
765 }
766
767 old_desc = old_branch_info->name;
768 if (!old_desc && old_branch_info->commit)
769 old_desc = oid_to_hex(&old_branch_info->commit->object.oid);
770
771 reflog_msg = getenv("GIT_REFLOG_ACTION");
772 if (!reflog_msg)
773 strbuf_addf(&msg, "checkout: moving from %s to %s",
774 old_desc ? old_desc : "(invalid)", new_branch_info->name);
775 else
776 strbuf_insert(&msg, 0, reflog_msg, strlen(reflog_msg));
777
778 if (!strcmp(new_branch_info->name, "HEAD") && !new_branch_info->path && !opts->force_detach) {
779 /* Nothing to do. */
780 } else if (opts->force_detach || !new_branch_info->path) { /* No longer on any branch. */
781 update_ref(msg.buf, "HEAD", &new_branch_info->commit->object.oid, NULL,
782 REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
783 if (!opts->quiet) {
784 if (old_branch_info->path &&
785 advice_detached_head && !opts->force_detach)
786 detach_advice(new_branch_info->name);
787 describe_detached_head(_("HEAD is now at"), new_branch_info->commit);
788 }
789 } else if (new_branch_info->path) { /* Switch branches. */
790 if (create_symref("HEAD", new_branch_info->path, msg.buf) < 0)
791 die(_("unable to update HEAD"));
792 if (!opts->quiet) {
793 if (old_branch_info->path && !strcmp(new_branch_info->path, old_branch_info->path)) {
794 if (opts->new_branch_force)
795 fprintf(stderr, _("Reset branch '%s'\n"),
796 new_branch_info->name);
797 else
798 fprintf(stderr, _("Already on '%s'\n"),
799 new_branch_info->name);
800 } else if (opts->new_branch) {
801 if (opts->branch_exists)
802 fprintf(stderr, _("Switched to and reset branch '%s'\n"), new_branch_info->name);
803 else
804 fprintf(stderr, _("Switched to a new branch '%s'\n"), new_branch_info->name);
805 } else {
806 fprintf(stderr, _("Switched to branch '%s'\n"),
807 new_branch_info->name);
808 }
809 }
810 if (old_branch_info->path && old_branch_info->name) {
811 if (!ref_exists(old_branch_info->path) && reflog_exists(old_branch_info->path))
812 delete_reflog(old_branch_info->path);
813 }
814 }
815 remove_branch_state();
816 strbuf_release(&msg);
817 if (!opts->quiet &&
818 (new_branch_info->path || (!opts->force_detach && !strcmp(new_branch_info->name, "HEAD"))))
819 report_tracking(new_branch_info);
820 }
821
822 static int add_pending_uninteresting_ref(const char *refname,
823 const struct object_id *oid,
824 int flags, void *cb_data)
825 {
826 add_pending_oid(cb_data, refname, oid, UNINTERESTING);
827 return 0;
828 }
829
830 static void describe_one_orphan(struct strbuf *sb, struct commit *commit)
831 {
832 strbuf_addstr(sb, " ");
833 strbuf_add_unique_abbrev(sb, &commit->object.oid, DEFAULT_ABBREV);
834 strbuf_addch(sb, ' ');
835 if (!parse_commit(commit))
836 pp_commit_easy(CMIT_FMT_ONELINE, commit, sb);
837 strbuf_addch(sb, '\n');
838 }
839
840 #define ORPHAN_CUTOFF 4
841 static void suggest_reattach(struct commit *commit, struct rev_info *revs)
842 {
843 struct commit *c, *last = NULL;
844 struct strbuf sb = STRBUF_INIT;
845 int lost = 0;
846 while ((c = get_revision(revs)) != NULL) {
847 if (lost < ORPHAN_CUTOFF)
848 describe_one_orphan(&sb, c);
849 last = c;
850 lost++;
851 }
852 if (ORPHAN_CUTOFF < lost) {
853 int more = lost - ORPHAN_CUTOFF;
854 if (more == 1)
855 describe_one_orphan(&sb, last);
856 else
857 strbuf_addf(&sb, _(" ... and %d more.\n"), more);
858 }
859
860 fprintf(stderr,
861 Q_(
862 /* The singular version */
863 "Warning: you are leaving %d commit behind, "
864 "not connected to\n"
865 "any of your branches:\n\n"
866 "%s\n",
867 /* The plural version */
868 "Warning: you are leaving %d commits behind, "
869 "not connected to\n"
870 "any of your branches:\n\n"
871 "%s\n",
872 /* Give ngettext() the count */
873 lost),
874 lost,
875 sb.buf);
876 strbuf_release(&sb);
877
878 if (advice_detached_head)
879 fprintf(stderr,
880 Q_(
881 /* The singular version */
882 "If you want to keep it by creating a new branch, "
883 "this may be a good time\nto do so with:\n\n"
884 " git branch <new-branch-name> %s\n\n",
885 /* The plural version */
886 "If you want to keep them by creating a new branch, "
887 "this may be a good time\nto do so with:\n\n"
888 " git branch <new-branch-name> %s\n\n",
889 /* Give ngettext() the count */
890 lost),
891 find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
892 }
893
894 /*
895 * We are about to leave commit that was at the tip of a detached
896 * HEAD. If it is not reachable from any ref, this is the last chance
897 * for the user to do so without resorting to reflog.
898 */
899 static void orphaned_commit_warning(struct commit *old_commit, struct commit *new_commit)
900 {
901 struct rev_info revs;
902 struct object *object = &old_commit->object;
903
904 repo_init_revisions(the_repository, &revs, NULL);
905 setup_revisions(0, NULL, &revs, NULL);
906
907 object->flags &= ~UNINTERESTING;
908 add_pending_object(&revs, object, oid_to_hex(&object->oid));
909
910 for_each_ref(add_pending_uninteresting_ref, &revs);
911 add_pending_oid(&revs, "HEAD", &new_commit->object.oid, UNINTERESTING);
912
913 if (prepare_revision_walk(&revs))
914 die(_("internal error in revision walk"));
915 if (!(old_commit->object.flags & UNINTERESTING))
916 suggest_reattach(old_commit, &revs);
917 else
918 describe_detached_head(_("Previous HEAD position was"), old_commit);
919
920 /* Clean up objects used, as they will be reused. */
921 clear_commit_marks_all(ALL_REV_FLAGS);
922 }
923
924 static int switch_branches(const struct checkout_opts *opts,
925 struct branch_info *new_branch_info)
926 {
927 int ret = 0;
928 struct branch_info old_branch_info;
929 void *path_to_free;
930 struct object_id rev;
931 int flag, writeout_error = 0;
932 memset(&old_branch_info, 0, sizeof(old_branch_info));
933 old_branch_info.path = path_to_free = resolve_refdup("HEAD", 0, &rev, &flag);
934 if (old_branch_info.path)
935 old_branch_info.commit = lookup_commit_reference_gently(the_repository, &rev, 1);
936 if (!(flag & REF_ISSYMREF))
937 old_branch_info.path = NULL;
938
939 if (old_branch_info.path)
940 skip_prefix(old_branch_info.path, "refs/heads/", &old_branch_info.name);
941
942 if (!new_branch_info->name) {
943 new_branch_info->name = "HEAD";
944 new_branch_info->commit = old_branch_info.commit;
945 if (!new_branch_info->commit)
946 die(_("You are on a branch yet to be born"));
947 parse_commit_or_die(new_branch_info->commit);
948 }
949
950 /* optimize the "checkout -b <new_branch> path */
951 if (skip_merge_working_tree(opts, &old_branch_info, new_branch_info)) {
952 if (!checkout_optimize_new_branch && !opts->quiet) {
953 if (read_cache_preload(NULL) < 0)
954 return error(_("index file corrupt"));
955 show_local_changes(&new_branch_info->commit->object, &opts->diff_options);
956 }
957 } else {
958 ret = merge_working_tree(opts, &old_branch_info, new_branch_info, &writeout_error);
959 if (ret) {
960 free(path_to_free);
961 return ret;
962 }
963 }
964
965 if (!opts->quiet && !old_branch_info.path && old_branch_info.commit && new_branch_info->commit != old_branch_info.commit)
966 orphaned_commit_warning(old_branch_info.commit, new_branch_info->commit);
967
968 update_refs_for_switch(opts, &old_branch_info, new_branch_info);
969
970 ret = post_checkout_hook(old_branch_info.commit, new_branch_info->commit, 1);
971 free(path_to_free);
972 return ret || writeout_error;
973 }
974
975 static int git_checkout_config(const char *var, const char *value, void *cb)
976 {
977 if (!strcmp(var, "checkout.optimizenewbranch")) {
978 checkout_optimize_new_branch = git_config_bool(var, value);
979 return 0;
980 }
981
982 if (!strcmp(var, "diff.ignoresubmodules")) {
983 struct checkout_opts *opts = cb;
984 handle_ignore_submodules_arg(&opts->diff_options, value);
985 return 0;
986 }
987
988 if (starts_with(var, "submodule."))
989 return git_default_submodule_config(var, value, NULL);
990
991 return git_xmerge_config(var, value, NULL);
992 }
993
994 static int parse_branchname_arg(int argc, const char **argv,
995 int dwim_new_local_branch_ok,
996 struct branch_info *new_branch_info,
997 struct checkout_opts *opts,
998 struct object_id *rev,
999 int *dwim_remotes_matched)
1000 {
1001 struct tree **source_tree = &opts->source_tree;
1002 const char **new_branch = &opts->new_branch;
1003 int argcount = 0;
1004 struct object_id branch_rev;
1005 const char *arg;
1006 int dash_dash_pos;
1007 int has_dash_dash = 0;
1008 int i;
1009
1010 /*
1011 * case 1: git checkout <ref> -- [<paths>]
1012 *
1013 * <ref> must be a valid tree, everything after the '--' must be
1014 * a path.
1015 *
1016 * case 2: git checkout -- [<paths>]
1017 *
1018 * everything after the '--' must be paths.
1019 *
1020 * case 3: git checkout <something> [--]
1021 *
1022 * (a) If <something> is a commit, that is to
1023 * switch to the branch or detach HEAD at it. As a special case,
1024 * if <something> is A...B (missing A or B means HEAD but you can
1025 * omit at most one side), and if there is a unique merge base
1026 * between A and B, A...B names that merge base.
1027 *
1028 * (b) If <something> is _not_ a commit, either "--" is present
1029 * or <something> is not a path, no -t or -b was given, and
1030 * and there is a tracking branch whose name is <something>
1031 * in one and only one remote (or if the branch exists on the
1032 * remote named in checkout.defaultRemote), then this is a
1033 * short-hand to fork local <something> from that
1034 * remote-tracking branch.
1035 *
1036 * (c) Otherwise, if "--" is present, treat it like case (1).
1037 *
1038 * (d) Otherwise :
1039 * - if it's a reference, treat it like case (1)
1040 * - else if it's a path, treat it like case (2)
1041 * - else: fail.
1042 *
1043 * case 4: git checkout <something> <paths>
1044 *
1045 * The first argument must not be ambiguous.
1046 * - If it's *only* a reference, treat it like case (1).
1047 * - If it's only a path, treat it like case (2).
1048 * - else: fail.
1049 *
1050 */
1051 if (!argc)
1052 return 0;
1053
1054 arg = argv[0];
1055 dash_dash_pos = -1;
1056 for (i = 0; i < argc; i++) {
1057 if (!strcmp(argv[i], "--")) {
1058 dash_dash_pos = i;
1059 break;
1060 }
1061 }
1062 if (dash_dash_pos == 0)
1063 return 1; /* case (2) */
1064 else if (dash_dash_pos == 1)
1065 has_dash_dash = 1; /* case (3) or (1) */
1066 else if (dash_dash_pos >= 2)
1067 die(_("only one reference expected, %d given."), dash_dash_pos);
1068
1069 if (!strcmp(arg, "-"))
1070 arg = "@{-1}";
1071
1072 if (get_oid_mb(arg, rev)) {
1073 /*
1074 * Either case (3) or (4), with <something> not being
1075 * a commit, or an attempt to use case (1) with an
1076 * invalid ref.
1077 *
1078 * It's likely an error, but we need to find out if
1079 * we should auto-create the branch, case (3).(b).
1080 */
1081 int recover_with_dwim = dwim_new_local_branch_ok;
1082
1083 if (!has_dash_dash &&
1084 (check_filename(opts->prefix, arg) || !no_wildcard(arg)))
1085 recover_with_dwim = 0;
1086 /*
1087 * Accept "git checkout foo" and "git checkout foo --"
1088 * as candidates for dwim.
1089 */
1090 if (!(argc == 1 && !has_dash_dash) &&
1091 !(argc == 2 && has_dash_dash))
1092 recover_with_dwim = 0;
1093
1094 if (recover_with_dwim) {
1095 const char *remote = unique_tracking_name(arg, rev,
1096 dwim_remotes_matched);
1097 if (remote) {
1098 *new_branch = arg;
1099 arg = remote;
1100 /* DWIMmed to create local branch, case (3).(b) */
1101 } else {
1102 recover_with_dwim = 0;
1103 }
1104 }
1105
1106 if (!recover_with_dwim) {
1107 if (has_dash_dash)
1108 die(_("invalid reference: %s"), arg);
1109 return argcount;
1110 }
1111 }
1112
1113 /* we can't end up being in (2) anymore, eat the argument */
1114 argcount++;
1115 argv++;
1116 argc--;
1117
1118 new_branch_info->name = arg;
1119 setup_branch_path(new_branch_info);
1120
1121 if (!check_refname_format(new_branch_info->path, 0) &&
1122 !read_ref(new_branch_info->path, &branch_rev))
1123 oidcpy(rev, &branch_rev);
1124 else
1125 new_branch_info->path = NULL; /* not an existing branch */
1126
1127 new_branch_info->commit = lookup_commit_reference_gently(the_repository, rev, 1);
1128 if (!new_branch_info->commit) {
1129 /* not a commit */
1130 *source_tree = parse_tree_indirect(rev);
1131 } else {
1132 parse_commit_or_die(new_branch_info->commit);
1133 *source_tree = get_commit_tree(new_branch_info->commit);
1134 }
1135
1136 if (!*source_tree) /* case (1): want a tree */
1137 die(_("reference is not a tree: %s"), arg);
1138 if (!has_dash_dash) { /* case (3).(d) -> (1) */
1139 /*
1140 * Do not complain the most common case
1141 * git checkout branch
1142 * even if there happen to be a file called 'branch';
1143 * it would be extremely annoying.
1144 */
1145 if (argc)
1146 verify_non_filename(opts->prefix, arg);
1147 } else {
1148 argcount++;
1149 argv++;
1150 argc--;
1151 }
1152
1153 return argcount;
1154 }
1155
1156 static int switch_unborn_to_new_branch(const struct checkout_opts *opts)
1157 {
1158 int status;
1159 struct strbuf branch_ref = STRBUF_INIT;
1160
1161 if (!opts->new_branch)
1162 die(_("You are on a branch yet to be born"));
1163 strbuf_addf(&branch_ref, "refs/heads/%s", opts->new_branch);
1164 status = create_symref("HEAD", branch_ref.buf, "checkout -b");
1165 strbuf_release(&branch_ref);
1166 if (!opts->quiet)
1167 fprintf(stderr, _("Switched to a new branch '%s'\n"),
1168 opts->new_branch);
1169 return status;
1170 }
1171
1172 static int checkout_branch(struct checkout_opts *opts,
1173 struct branch_info *new_branch_info)
1174 {
1175 if (opts->pathspec.nr)
1176 die(_("paths cannot be used with switching branches"));
1177
1178 if (opts->patch_mode)
1179 die(_("'%s' cannot be used with switching branches"),
1180 "--patch");
1181
1182 if (opts->writeout_stage)
1183 die(_("'%s' cannot be used with switching branches"),
1184 "--ours/--theirs");
1185
1186 if (opts->force && opts->merge)
1187 die(_("'%s' cannot be used with '%s'"), "-f", "-m");
1188
1189 if (opts->force_detach && opts->new_branch)
1190 die(_("'%s' cannot be used with '%s'"),
1191 "--detach", "-b/-B/--orphan");
1192
1193 if (opts->new_orphan_branch) {
1194 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1195 die(_("'%s' cannot be used with '%s'"), "--orphan", "-t");
1196 } else if (opts->force_detach) {
1197 if (opts->track != BRANCH_TRACK_UNSPECIFIED)
1198 die(_("'%s' cannot be used with '%s'"), "--detach", "-t");
1199 } else if (opts->track == BRANCH_TRACK_UNSPECIFIED)
1200 opts->track = git_branch_track;
1201
1202 if (new_branch_info->name && !new_branch_info->commit)
1203 die(_("Cannot switch branch to a non-commit '%s'"),
1204 new_branch_info->name);
1205
1206 if (new_branch_info->path && !opts->force_detach && !opts->new_branch &&
1207 !opts->ignore_other_worktrees) {
1208 int flag;
1209 char *head_ref = resolve_refdup("HEAD", 0, NULL, &flag);
1210 if (head_ref &&
1211 (!(flag & REF_ISSYMREF) || strcmp(head_ref, new_branch_info->path)))
1212 die_if_checked_out(new_branch_info->path, 1);
1213 free(head_ref);
1214 }
1215
1216 if (!new_branch_info->commit && opts->new_branch) {
1217 struct object_id rev;
1218 int flag;
1219
1220 if (!read_ref_full("HEAD", 0, &rev, &flag) &&
1221 (flag & REF_ISSYMREF) && is_null_oid(&rev))
1222 return switch_unborn_to_new_branch(opts);
1223 }
1224 return switch_branches(opts, new_branch_info);
1225 }
1226
1227 int cmd_checkout(int argc, const char **argv, const char *prefix)
1228 {
1229 struct checkout_opts opts;
1230 struct branch_info new_branch_info;
1231 char *conflict_style = NULL;
1232 int dwim_new_local_branch = 1;
1233 int dwim_remotes_matched = 0;
1234 struct option options[] = {
1235 OPT__QUIET(&opts.quiet, N_("suppress progress reporting")),
1236 OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
1237 N_("create and checkout a new branch")),
1238 OPT_STRING('B', NULL, &opts.new_branch_force, N_("branch"),
1239 N_("create/reset and checkout a branch")),
1240 OPT_BOOL('l', NULL, &opts.new_branch_log, N_("create reflog for new branch")),
1241 OPT_BOOL(0, "detach", &opts.force_detach, N_("detach HEAD at named commit")),
1242 OPT_SET_INT('t', "track", &opts.track, N_("set upstream info for new branch"),
1243 BRANCH_TRACK_EXPLICIT),
1244 OPT_STRING(0, "orphan", &opts.new_orphan_branch, N_("new-branch"), N_("new unparented branch")),
1245 OPT_SET_INT_F('2', "ours", &opts.writeout_stage,
1246 N_("checkout our version for unmerged files"),
1247 2, PARSE_OPT_NONEG),
1248 OPT_SET_INT_F('3', "theirs", &opts.writeout_stage,
1249 N_("checkout their version for unmerged files"),
1250 3, PARSE_OPT_NONEG),
1251 OPT__FORCE(&opts.force, N_("force checkout (throw away local modifications)"),
1252 PARSE_OPT_NOCOMPLETE),
1253 OPT_BOOL('m', "merge", &opts.merge, N_("perform a 3-way merge with the new branch")),
1254 OPT_BOOL_F(0, "overwrite-ignore", &opts.overwrite_ignore,
1255 N_("update ignored files (default)"),
1256 PARSE_OPT_NOCOMPLETE),
1257 OPT_STRING(0, "conflict", &conflict_style, N_("style"),
1258 N_("conflict style (merge or diff3)")),
1259 OPT_BOOL('p', "patch", &opts.patch_mode, N_("select hunks interactively")),
1260 OPT_BOOL(0, "ignore-skip-worktree-bits", &opts.ignore_skipworktree,
1261 N_("do not limit pathspecs to sparse entries only")),
1262 OPT_HIDDEN_BOOL(0, "guess", &dwim_new_local_branch,
1263 N_("second guess 'git checkout <no-such-branch>'")),
1264 OPT_BOOL(0, "ignore-other-worktrees", &opts.ignore_other_worktrees,
1265 N_("do not check if another worktree is holding the given ref")),
1266 { OPTION_CALLBACK, 0, "recurse-submodules", NULL,
1267 "checkout", "control recursive updating of submodules",
1268 PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater },
1269 OPT_BOOL(0, "progress", &opts.show_progress, N_("force progress reporting")),
1270 OPT_END(),
1271 };
1272
1273 memset(&opts, 0, sizeof(opts));
1274 memset(&new_branch_info, 0, sizeof(new_branch_info));
1275 opts.overwrite_ignore = 1;
1276 opts.prefix = prefix;
1277 opts.show_progress = -1;
1278
1279 git_config(git_checkout_config, &opts);
1280
1281 opts.track = BRANCH_TRACK_UNSPECIFIED;
1282
1283 argc = parse_options(argc, argv, prefix, options, checkout_usage,
1284 PARSE_OPT_KEEP_DASHDASH);
1285
1286 if (opts.show_progress < 0) {
1287 if (opts.quiet)
1288 opts.show_progress = 0;
1289 else
1290 opts.show_progress = isatty(2);
1291 }
1292
1293 if (conflict_style) {
1294 opts.merge = 1; /* implied */
1295 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
1296 }
1297
1298 if ((!!opts.new_branch + !!opts.new_branch_force + !!opts.new_orphan_branch) > 1)
1299 die(_("-b, -B and --orphan are mutually exclusive"));
1300
1301 /*
1302 * From here on, new_branch will contain the branch to be checked out,
1303 * and new_branch_force and new_orphan_branch will tell us which one of
1304 * -b/-B/--orphan is being used.
1305 */
1306 if (opts.new_branch_force)
1307 opts.new_branch = opts.new_branch_force;
1308
1309 if (opts.new_orphan_branch)
1310 opts.new_branch = opts.new_orphan_branch;
1311
1312 /* --track without -b/-B/--orphan should DWIM */
1313 if (opts.track != BRANCH_TRACK_UNSPECIFIED && !opts.new_branch) {
1314 const char *argv0 = argv[0];
1315 if (!argc || !strcmp(argv0, "--"))
1316 die(_("--track needs a branch name"));
1317 skip_prefix(argv0, "refs/", &argv0);
1318 skip_prefix(argv0, "remotes/", &argv0);
1319 argv0 = strchr(argv0, '/');
1320 if (!argv0 || !argv0[1])
1321 die(_("missing branch name; try -b"));
1322 opts.new_branch = argv0 + 1;
1323 }
1324
1325 /*
1326 * Extract branch name from command line arguments, so
1327 * all that is left is pathspecs.
1328 *
1329 * Handle
1330 *
1331 * 1) git checkout <tree> -- [<paths>]
1332 * 2) git checkout -- [<paths>]
1333 * 3) git checkout <something> [<paths>]
1334 *
1335 * including "last branch" syntax and DWIM-ery for names of
1336 * remote branches, erroring out for invalid or ambiguous cases.
1337 */
1338 if (argc) {
1339 struct object_id rev;
1340 int dwim_ok =
1341 !opts.patch_mode &&
1342 dwim_new_local_branch &&
1343 opts.track == BRANCH_TRACK_UNSPECIFIED &&
1344 !opts.new_branch;
1345 int n = parse_branchname_arg(argc, argv, dwim_ok,
1346 &new_branch_info, &opts, &rev,
1347 &dwim_remotes_matched);
1348 argv += n;
1349 argc -= n;
1350 }
1351
1352 if (argc) {
1353 parse_pathspec(&opts.pathspec, 0,
1354 opts.patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0,
1355 prefix, argv);
1356
1357 if (!opts.pathspec.nr)
1358 die(_("invalid path specification"));
1359
1360 /*
1361 * Try to give more helpful suggestion.
1362 * new_branch && argc > 1 will be caught later.
1363 */
1364 if (opts.new_branch && argc == 1)
1365 die(_("'%s' is not a commit and a branch '%s' cannot be created from it"),
1366 argv[0], opts.new_branch);
1367
1368 if (opts.force_detach)
1369 die(_("git checkout: --detach does not take a path argument '%s'"),
1370 argv[0]);
1371
1372 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
1373 die(_("git checkout: --ours/--theirs, --force and --merge are incompatible when\n"
1374 "checking out of the index."));
1375 }
1376
1377 if (opts.new_branch) {
1378 struct strbuf buf = STRBUF_INIT;
1379
1380 if (opts.new_branch_force)
1381 opts.branch_exists = validate_branchname(opts.new_branch, &buf);
1382 else
1383 opts.branch_exists =
1384 validate_new_branchname(opts.new_branch, &buf, 0);
1385 strbuf_release(&buf);
1386 }
1387
1388 UNLEAK(opts);
1389 if (opts.patch_mode || opts.pathspec.nr) {
1390 int ret = checkout_paths(&opts, new_branch_info.name);
1391 if (ret && dwim_remotes_matched > 1 &&
1392 advice_checkout_ambiguous_remote_branch_name)
1393 advise(_("'%s' matched more than one remote tracking branch.\n"
1394 "We found %d remotes with a reference that matched. So we fell back\n"
1395 "on trying to resolve the argument as a path, but failed there too!\n"
1396 "\n"
1397 "If you meant to check out a remote tracking branch on, e.g. 'origin',\n"
1398 "you can do so by fully qualifying the name with the --track option:\n"
1399 "\n"
1400 " git checkout --track origin/<name>\n"
1401 "\n"
1402 "If you'd like to always have checkouts of an ambiguous <name> prefer\n"
1403 "one remote, e.g. the 'origin' remote, consider setting\n"
1404 "checkout.defaultRemote=origin in your config."),
1405 argv[0],
1406 dwim_remotes_matched);
1407 return ret;
1408 } else {
1409 return checkout_branch(&opts, &new_branch_info);
1410 }
1411 }