gitk: Second try to work around the command line limit on Windows
[git/dscho.git] / builtin / checkout.c
blobc3825219c1efbd4939af6d18bcad6efcfa74f406
1 #include "cache.h"
2 #include "builtin.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"
22 static const char * const checkout_usage[] = {
23 "git checkout [options] <branch>",
24 "git checkout [options] [<branch>] -- <file>...",
25 NULL,
28 struct checkout_opts {
29 int quiet;
30 int merge;
31 int force;
32 int writeout_stage;
33 int writeout_error;
35 const char *new_branch;
36 const char *new_orphan_branch;
37 int new_branch_log;
38 enum branch_track track;
41 static int post_checkout_hook(struct commit *old, struct commit *new,
42 int changed)
44 return run_hook(NULL, "post-checkout",
45 sha1_to_hex(old ? old->object.sha1 : null_sha1),
46 sha1_to_hex(new ? new->object.sha1 : null_sha1),
47 changed ? "1" : "0", NULL);
48 /* "new" can be NULL when checking out from the index before
49 a commit exists. */
53 static int update_some(const unsigned char *sha1, const char *base, int baselen,
54 const char *pathname, unsigned mode, int stage, void *context)
56 int len;
57 struct cache_entry *ce;
59 if (S_ISDIR(mode))
60 return READ_TREE_RECURSIVE;
62 len = baselen + strlen(pathname);
63 ce = xcalloc(1, cache_entry_size(len));
64 hashcpy(ce->sha1, sha1);
65 memcpy(ce->name, base, baselen);
66 memcpy(ce->name + baselen, pathname, len - baselen);
67 ce->ce_flags = create_ce_flags(len, 0);
68 ce->ce_mode = create_ce_mode(mode);
69 add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
70 return 0;
73 static int read_tree_some(struct tree *tree, const char **pathspec)
75 read_tree_recursive(tree, "", 0, 0, pathspec, update_some, NULL);
77 /* update the index with the given tree's info
78 * for all args, expanding wildcards, and exit
79 * with any non-zero return code.
81 return 0;
84 static int skip_same_name(struct cache_entry *ce, int pos)
86 while (++pos < active_nr &&
87 !strcmp(active_cache[pos]->name, ce->name))
88 ; /* skip */
89 return pos;
92 static int check_stage(int stage, struct cache_entry *ce, int pos)
94 while (pos < active_nr &&
95 !strcmp(active_cache[pos]->name, ce->name)) {
96 if (ce_stage(active_cache[pos]) == stage)
97 return 0;
98 pos++;
100 return error("path '%s' does not have %s version",
101 ce->name,
102 (stage == 2) ? "our" : "their");
105 static int check_all_stages(struct cache_entry *ce, int pos)
107 if (ce_stage(ce) != 1 ||
108 active_nr <= pos + 2 ||
109 strcmp(active_cache[pos+1]->name, ce->name) ||
110 ce_stage(active_cache[pos+1]) != 2 ||
111 strcmp(active_cache[pos+2]->name, ce->name) ||
112 ce_stage(active_cache[pos+2]) != 3)
113 return error("path '%s' does not have all three versions",
114 ce->name);
115 return 0;
118 static int checkout_stage(int stage, struct cache_entry *ce, int pos,
119 struct checkout *state)
121 while (pos < active_nr &&
122 !strcmp(active_cache[pos]->name, ce->name)) {
123 if (ce_stage(active_cache[pos]) == stage)
124 return checkout_entry(active_cache[pos], state, NULL);
125 pos++;
127 return error("path '%s' does not have %s version",
128 ce->name,
129 (stage == 2) ? "our" : "their");
132 static int checkout_merged(int pos, struct checkout *state)
134 struct cache_entry *ce = active_cache[pos];
135 const char *path = ce->name;
136 mmfile_t ancestor, ours, theirs;
137 int status;
138 unsigned char sha1[20];
139 mmbuffer_t result_buf;
141 if (ce_stage(ce) != 1 ||
142 active_nr <= pos + 2 ||
143 strcmp(active_cache[pos+1]->name, path) ||
144 ce_stage(active_cache[pos+1]) != 2 ||
145 strcmp(active_cache[pos+2]->name, path) ||
146 ce_stage(active_cache[pos+2]) != 3)
147 return error("path '%s' does not have all 3 versions", path);
149 read_mmblob(&ancestor, active_cache[pos]->sha1);
150 read_mmblob(&ours, active_cache[pos+1]->sha1);
151 read_mmblob(&theirs, active_cache[pos+2]->sha1);
153 status = ll_merge(&result_buf, path, &ancestor, "base",
154 &ours, "ours", &theirs, "theirs", 0);
155 free(ancestor.ptr);
156 free(ours.ptr);
157 free(theirs.ptr);
158 if (status < 0 || !result_buf.ptr) {
159 free(result_buf.ptr);
160 return error("path '%s': cannot merge", path);
164 * NEEDSWORK:
165 * There is absolutely no reason to write this as a blob object
166 * and create a phony cache entry just to leak. This hack is
167 * primarily to get to the write_entry() machinery that massages
168 * the contents to work-tree format and writes out which only
169 * allows it for a cache entry. The code in write_entry() needs
170 * to be refactored to allow us to feed a <buffer, size, mode>
171 * instead of a cache entry. Such a refactoring would help
172 * merge_recursive as well (it also writes the merge result to the
173 * object database even when it may contain conflicts).
175 if (write_sha1_file(result_buf.ptr, result_buf.size,
176 blob_type, sha1))
177 die("Unable to add merge result for '%s'", path);
178 ce = make_cache_entry(create_ce_mode(active_cache[pos+1]->ce_mode),
179 sha1,
180 path, 2, 0);
181 if (!ce)
182 die("make_cache_entry failed for path '%s'", path);
183 status = checkout_entry(ce, state, NULL);
184 return status;
187 static int checkout_paths(struct tree *source_tree, const char **pathspec,
188 struct checkout_opts *opts)
190 int pos;
191 struct checkout state;
192 static char *ps_matched;
193 unsigned char rev[20];
194 int flag;
195 struct commit *head;
196 int errs = 0;
197 int stage = opts->writeout_stage;
198 int merge = opts->merge;
199 int newfd;
200 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
202 newfd = hold_locked_index(lock_file, 1);
203 if (read_cache_preload(pathspec) < 0)
204 return error("corrupt index file");
206 if (source_tree)
207 read_tree_some(source_tree, pathspec);
209 for (pos = 0; pathspec[pos]; pos++)
211 ps_matched = xcalloc(1, pos);
213 for (pos = 0; pos < active_nr; pos++) {
214 struct cache_entry *ce = active_cache[pos];
215 match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, ps_matched);
218 if (report_path_error(ps_matched, pathspec, 0))
219 return 1;
221 /* "checkout -m path" to recreate conflicted state */
222 if (opts->merge)
223 unmerge_cache(pathspec);
225 /* Any unmerged paths? */
226 for (pos = 0; pos < active_nr; pos++) {
227 struct cache_entry *ce = active_cache[pos];
228 if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
229 if (!ce_stage(ce))
230 continue;
231 if (opts->force) {
232 warning("path '%s' is unmerged", ce->name);
233 } else if (stage) {
234 errs |= check_stage(stage, ce, pos);
235 } else if (opts->merge) {
236 errs |= check_all_stages(ce, pos);
237 } else {
238 errs = 1;
239 error("path '%s' is unmerged", ce->name);
241 pos = skip_same_name(ce, pos) - 1;
244 if (errs)
245 return 1;
247 /* Now we are committed to check them out */
248 memset(&state, 0, sizeof(state));
249 state.force = 1;
250 state.refresh_cache = 1;
251 for (pos = 0; pos < active_nr; pos++) {
252 struct cache_entry *ce = active_cache[pos];
253 if (match_pathspec(pathspec, ce->name, ce_namelen(ce), 0, NULL)) {
254 if (!ce_stage(ce)) {
255 errs |= checkout_entry(ce, &state, NULL);
256 continue;
258 if (stage)
259 errs |= checkout_stage(stage, ce, pos, &state);
260 else if (merge)
261 errs |= checkout_merged(pos, &state);
262 pos = skip_same_name(ce, pos) - 1;
266 if (write_cache(newfd, active_cache, active_nr) ||
267 commit_locked_index(lock_file))
268 die("unable to write new index file");
270 resolve_ref("HEAD", rev, 0, &flag);
271 head = lookup_commit_reference_gently(rev, 1);
273 errs |= post_checkout_hook(head, head, 0);
274 return errs;
277 static void show_local_changes(struct object *head)
279 struct rev_info rev;
280 /* I think we want full paths, even if we're in a subdirectory. */
281 init_revisions(&rev, NULL);
282 rev.abbrev = 0;
283 rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
284 if (diff_setup_done(&rev.diffopt) < 0)
285 die("diff_setup_done failed");
286 add_pending_object(&rev, head, NULL);
287 run_diff_index(&rev, 0);
290 static void describe_detached_head(char *msg, struct commit *commit)
292 struct strbuf sb = STRBUF_INIT;
293 struct pretty_print_context ctx = {0};
294 parse_commit(commit);
295 pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, &ctx);
296 fprintf(stderr, "%s %s... %s\n", msg,
297 find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
298 strbuf_release(&sb);
301 static int reset_tree(struct tree *tree, struct checkout_opts *o, int worktree)
303 struct unpack_trees_options opts;
304 struct tree_desc tree_desc;
306 memset(&opts, 0, sizeof(opts));
307 opts.head_idx = -1;
308 opts.update = worktree;
309 opts.skip_unmerged = !worktree;
310 opts.reset = 1;
311 opts.merge = 1;
312 opts.fn = oneway_merge;
313 opts.verbose_update = !o->quiet;
314 opts.src_index = &the_index;
315 opts.dst_index = &the_index;
316 parse_tree(tree);
317 init_tree_desc(&tree_desc, tree->buffer, tree->size);
318 switch (unpack_trees(1, &tree_desc, &opts)) {
319 case -2:
320 o->writeout_error = 1;
322 * We return 0 nevertheless, as the index is all right
323 * and more importantly we have made best efforts to
324 * update paths in the work tree, and we cannot revert
325 * them.
327 case 0:
328 return 0;
329 default:
330 return 128;
334 struct branch_info {
335 const char *name; /* The short name used */
336 const char *path; /* The full name of a real branch */
337 struct commit *commit; /* The named commit */
340 static void setup_branch_path(struct branch_info *branch)
342 struct strbuf buf = STRBUF_INIT;
344 strbuf_branchname(&buf, branch->name);
345 if (strcmp(buf.buf, branch->name))
346 branch->name = xstrdup(buf.buf);
347 strbuf_splice(&buf, 0, 0, "refs/heads/", 11);
348 branch->path = strbuf_detach(&buf, NULL);
351 static int merge_working_tree(struct checkout_opts *opts,
352 struct branch_info *old, struct branch_info *new)
354 int ret;
355 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
356 int newfd = hold_locked_index(lock_file, 1);
358 if (read_cache_preload(NULL) < 0)
359 return error("corrupt index file");
361 resolve_undo_clear();
362 if (opts->force) {
363 ret = reset_tree(new->commit->tree, opts, 1);
364 if (ret)
365 return ret;
366 } else {
367 struct tree_desc trees[2];
368 struct tree *tree;
369 struct unpack_trees_options topts;
371 memset(&topts, 0, sizeof(topts));
372 topts.head_idx = -1;
373 topts.src_index = &the_index;
374 topts.dst_index = &the_index;
376 topts.msgs.not_uptodate_file = "You have local changes to '%s'; cannot switch branches.";
378 refresh_cache(REFRESH_QUIET);
380 if (unmerged_cache()) {
381 error("you need to resolve your current index first");
382 return 1;
385 /* 2-way merge to the new branch */
386 topts.initial_checkout = is_cache_unborn();
387 topts.update = 1;
388 topts.merge = 1;
389 topts.gently = opts->merge && old->commit;
390 topts.verbose_update = !opts->quiet;
391 topts.fn = twoway_merge;
392 topts.dir = xcalloc(1, sizeof(*topts.dir));
393 topts.dir->flags |= DIR_SHOW_IGNORED;
394 topts.dir->exclude_per_dir = ".gitignore";
395 tree = parse_tree_indirect(old->commit ?
396 old->commit->object.sha1 :
397 (unsigned char *)EMPTY_TREE_SHA1_BIN);
398 init_tree_desc(&trees[0], tree->buffer, tree->size);
399 tree = parse_tree_indirect(new->commit->object.sha1);
400 init_tree_desc(&trees[1], tree->buffer, tree->size);
402 ret = unpack_trees(2, trees, &topts);
403 if (ret == -1) {
405 * Unpack couldn't do a trivial merge; either
406 * give up or do a real merge, depending on
407 * whether the merge flag was used.
409 struct tree *result;
410 struct tree *work;
411 struct merge_options o;
412 if (!opts->merge)
413 return 1;
416 * Without old->commit, the below is the same as
417 * the two-tree unpack we already tried and failed.
419 if (!old->commit)
420 return 1;
422 /* Do more real merge */
425 * We update the index fully, then write the
426 * tree from the index, then merge the new
427 * branch with the current tree, with the old
428 * branch as the base. Then we reset the index
429 * (but not the working tree) to the new
430 * branch, leaving the working tree as the
431 * merged version, but skipping unmerged
432 * entries in the index.
435 add_files_to_cache(NULL, NULL, 0);
436 init_merge_options(&o);
437 o.verbosity = 0;
438 work = write_tree_from_memory(&o);
440 ret = reset_tree(new->commit->tree, opts, 1);
441 if (ret)
442 return ret;
443 o.ancestor = old->name;
444 o.branch1 = new->name;
445 o.branch2 = "local";
446 merge_trees(&o, new->commit->tree, work,
447 old->commit->tree, &result);
448 ret = reset_tree(new->commit->tree, opts, 0);
449 if (ret)
450 return ret;
454 if (write_cache(newfd, active_cache, active_nr) ||
455 commit_locked_index(lock_file))
456 die("unable to write new index file");
458 if (!opts->force && !opts->quiet)
459 show_local_changes(&new->commit->object);
461 return 0;
464 static void report_tracking(struct branch_info *new)
466 struct strbuf sb = STRBUF_INIT;
467 struct branch *branch = branch_get(new->name);
469 if (!format_tracking_info(branch, &sb))
470 return;
471 fputs(sb.buf, stdout);
472 strbuf_release(&sb);
475 static void detach_advice(const char *old_path, const char *new_name)
477 const char fmt[] =
478 "Note: checking out '%s'.\n\n"
479 "You are in 'detached HEAD' state. You can look around, make experimental\n"
480 "changes and commit them, and you can discard any commits you make in this\n"
481 "state without impacting any branches by performing another checkout.\n\n"
482 "If you want to create a new branch to retain commits you create, you may\n"
483 "do so (now or later) by using -b with the checkout command again. Example:\n\n"
484 " git checkout -b new_branch_name\n\n";
486 fprintf(stderr, fmt, new_name);
489 static void update_refs_for_switch(struct checkout_opts *opts,
490 struct branch_info *old,
491 struct branch_info *new)
493 struct strbuf msg = STRBUF_INIT;
494 const char *old_desc;
495 if (opts->new_branch) {
496 if (!opts->new_orphan_branch)
497 create_branch(old->name, opts->new_branch, new->name, 0,
498 opts->new_branch_log, opts->track);
499 new->name = opts->new_branch;
500 setup_branch_path(new);
503 old_desc = old->name;
504 if (!old_desc && old->commit)
505 old_desc = sha1_to_hex(old->commit->object.sha1);
506 strbuf_addf(&msg, "checkout: moving from %s to %s",
507 old_desc ? old_desc : "(invalid)", new->name);
509 if (new->path) {
510 create_symref("HEAD", new->path, msg.buf);
511 if (!opts->quiet) {
512 if (old->path && !strcmp(new->path, old->path))
513 fprintf(stderr, "Already on '%s'\n",
514 new->name);
515 else
516 fprintf(stderr, "Switched to%s branch '%s'\n",
517 opts->new_branch ? " a new" : "",
518 new->name);
520 } else if (strcmp(new->name, "HEAD")) {
521 update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
522 REF_NODEREF, DIE_ON_ERR);
523 if (!opts->quiet) {
524 if (old->path && advice_detached_head)
525 detach_advice(old->path, new->name);
526 describe_detached_head("HEAD is now at", new->commit);
529 remove_branch_state();
530 strbuf_release(&msg);
531 if (!opts->quiet && (new->path || !strcmp(new->name, "HEAD")))
532 report_tracking(new);
535 static int switch_branches(struct checkout_opts *opts, struct branch_info *new)
537 int ret = 0;
538 struct branch_info old;
539 unsigned char rev[20];
540 int flag;
541 memset(&old, 0, sizeof(old));
542 old.path = resolve_ref("HEAD", rev, 0, &flag);
543 old.commit = lookup_commit_reference_gently(rev, 1);
544 if (!(flag & REF_ISSYMREF))
545 old.path = NULL;
547 if (old.path && !prefixcmp(old.path, "refs/heads/"))
548 old.name = old.path + strlen("refs/heads/");
550 if (!new->name) {
551 new->name = "HEAD";
552 new->commit = old.commit;
553 if (!new->commit)
554 die("You are on a branch yet to be born");
555 parse_commit(new->commit);
558 ret = merge_working_tree(opts, &old, new);
559 if (ret)
560 return ret;
563 * If we were on a detached HEAD, but have now moved to
564 * a new commit, we want to mention the old commit once more
565 * to remind the user that it might be lost.
567 if (!opts->quiet && !old.path && old.commit && new->commit != old.commit)
568 describe_detached_head("Previous HEAD position was", old.commit);
570 update_refs_for_switch(opts, &old, new);
572 ret = post_checkout_hook(old.commit, new->commit, 1);
573 return ret || opts->writeout_error;
576 static int git_checkout_config(const char *var, const char *value, void *cb)
578 return git_xmerge_config(var, value, cb);
581 static int interactive_checkout(const char *revision, const char **pathspec,
582 struct checkout_opts *opts)
584 return run_add_interactive(revision, "--patch=checkout", pathspec);
587 struct tracking_name_data {
588 const char *name;
589 char *remote;
590 int unique;
593 static int check_tracking_name(const char *refname, const unsigned char *sha1,
594 int flags, void *cb_data)
596 struct tracking_name_data *cb = cb_data;
597 const char *slash;
599 if (prefixcmp(refname, "refs/remotes/"))
600 return 0;
601 slash = strchr(refname + 13, '/');
602 if (!slash || strcmp(slash + 1, cb->name))
603 return 0;
604 if (cb->remote) {
605 cb->unique = 0;
606 return 0;
608 cb->remote = xstrdup(refname);
609 return 0;
612 static const char *unique_tracking_name(const char *name)
614 struct tracking_name_data cb_data = { name, NULL, 1 };
615 for_each_ref(check_tracking_name, &cb_data);
616 if (cb_data.unique)
617 return cb_data.remote;
618 free(cb_data.remote);
619 return NULL;
622 int cmd_checkout(int argc, const char **argv, const char *prefix)
624 struct checkout_opts opts;
625 unsigned char rev[20];
626 const char *arg;
627 struct branch_info new;
628 struct tree *source_tree = NULL;
629 char *conflict_style = NULL;
630 int patch_mode = 0;
631 int dwim_new_local_branch = 1;
632 struct option options[] = {
633 OPT__QUIET(&opts.quiet),
634 OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"),
635 OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "log for new branch"),
636 OPT_SET_INT('t', "track", &opts.track, "track",
637 BRANCH_TRACK_EXPLICIT),
638 OPT_STRING(0, "orphan", &opts.new_orphan_branch, "new branch", "new unparented branch"),
639 OPT_SET_INT('2', "ours", &opts.writeout_stage, "stage",
641 OPT_SET_INT('3', "theirs", &opts.writeout_stage, "stage",
643 OPT_BOOLEAN('f', "force", &opts.force, "force"),
644 OPT_BOOLEAN('m', "merge", &opts.merge, "merge"),
645 OPT_STRING(0, "conflict", &conflict_style, "style",
646 "conflict style (merge or diff3)"),
647 OPT_BOOLEAN('p', "patch", &patch_mode, "select hunks interactively"),
648 { OPTION_BOOLEAN, 0, "guess", &dwim_new_local_branch, NULL,
649 "second guess 'git checkout no-such-branch'",
650 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
651 OPT_END(),
653 int has_dash_dash;
655 memset(&opts, 0, sizeof(opts));
656 memset(&new, 0, sizeof(new));
658 git_config(git_checkout_config, NULL);
660 opts.track = BRANCH_TRACK_UNSPECIFIED;
662 argc = parse_options(argc, argv, prefix, options, checkout_usage,
663 PARSE_OPT_KEEP_DASHDASH);
665 if (patch_mode && (opts.track > 0 || opts.new_branch
666 || opts.new_branch_log || opts.merge || opts.force))
667 die ("--patch is incompatible with all other options");
669 /* --track without -b should DWIM */
670 if (0 < opts.track && !opts.new_branch) {
671 const char *argv0 = argv[0];
672 if (!argc || !strcmp(argv0, "--"))
673 die ("--track needs a branch name");
674 if (!prefixcmp(argv0, "refs/"))
675 argv0 += 5;
676 if (!prefixcmp(argv0, "remotes/"))
677 argv0 += 8;
678 argv0 = strchr(argv0, '/');
679 if (!argv0 || !argv0[1])
680 die ("Missing branch name; try -b");
681 opts.new_branch = argv0 + 1;
684 if (opts.new_orphan_branch) {
685 if (opts.new_branch)
686 die("--orphan and -b are mutually exclusive");
687 if (opts.track > 0 || opts.new_branch_log)
688 die("--orphan cannot be used with -t or -l");
689 opts.new_branch = opts.new_orphan_branch;
692 if (conflict_style) {
693 opts.merge = 1; /* implied */
694 git_xmerge_config("merge.conflictstyle", conflict_style, NULL);
697 if (opts.force && opts.merge)
698 die("git checkout: -f and -m are incompatible");
701 * case 1: git checkout <ref> -- [<paths>]
703 * <ref> must be a valid tree, everything after the '--' must be
704 * a path.
706 * case 2: git checkout -- [<paths>]
708 * everything after the '--' must be paths.
710 * case 3: git checkout <something> [<paths>]
712 * With no paths, if <something> is a commit, that is to
713 * switch to the branch or detach HEAD at it. As a special case,
714 * if <something> is A...B (missing A or B means HEAD but you can
715 * omit at most one side), and if there is a unique merge base
716 * between A and B, A...B names that merge base.
718 * With no paths, if <something> is _not_ a commit, no -t nor -b
719 * was given, and there is a tracking branch whose name is
720 * <something> in one and only one remote, then this is a short-hand
721 * to fork local <something> from that remote tracking branch.
723 * Otherwise <something> shall not be ambiguous.
724 * - If it's *only* a reference, treat it like case (1).
725 * - If it's only a path, treat it like case (2).
726 * - else: fail.
729 if (argc) {
730 if (!strcmp(argv[0], "--")) { /* case (2) */
731 argv++;
732 argc--;
733 goto no_reference;
736 arg = argv[0];
737 has_dash_dash = (argc > 1) && !strcmp(argv[1], "--");
739 if (!strcmp(arg, "-"))
740 arg = "@{-1}";
742 if (get_sha1_mb(arg, rev)) {
743 if (has_dash_dash) /* case (1) */
744 die("invalid reference: %s", arg);
745 if (!patch_mode &&
746 dwim_new_local_branch &&
747 opts.track == BRANCH_TRACK_UNSPECIFIED &&
748 !opts.new_branch &&
749 !check_filename(NULL, arg) &&
750 argc == 1) {
751 const char *remote = unique_tracking_name(arg);
752 if (!remote || get_sha1(remote, rev))
753 goto no_reference;
754 opts.new_branch = arg;
755 arg = remote;
756 /* DWIMmed to create local branch */
758 else
759 goto no_reference;
762 /* we can't end up being in (2) anymore, eat the argument */
763 argv++;
764 argc--;
766 new.name = arg;
767 if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
768 setup_branch_path(&new);
770 if ((check_ref_format(new.path) == CHECK_REF_FORMAT_OK) &&
771 resolve_ref(new.path, rev, 1, NULL))
773 else
774 new.path = NULL;
775 parse_commit(new.commit);
776 source_tree = new.commit->tree;
777 } else
778 source_tree = parse_tree_indirect(rev);
780 if (!source_tree) /* case (1): want a tree */
781 die("reference is not a tree: %s", arg);
782 if (!has_dash_dash) {/* case (3 -> 1) */
784 * Do not complain the most common case
785 * git checkout branch
786 * even if there happen to be a file called 'branch';
787 * it would be extremely annoying.
789 if (argc)
790 verify_non_filename(NULL, arg);
792 else {
793 argv++;
794 argc--;
798 no_reference:
800 if (opts.track == BRANCH_TRACK_UNSPECIFIED)
801 opts.track = git_branch_track;
803 if (argc) {
804 const char **pathspec = get_pathspec(prefix, argv);
806 if (!pathspec)
807 die("invalid path specification");
809 if (patch_mode)
810 return interactive_checkout(new.name, pathspec, &opts);
812 /* Checkout paths */
813 if (opts.new_branch) {
814 if (argc == 1) {
815 die("git checkout: updating paths is incompatible with switching branches.\nDid you intend to checkout '%s' which can not be resolved as commit?", argv[0]);
816 } else {
817 die("git checkout: updating paths is incompatible with switching branches.");
821 if (1 < !!opts.writeout_stage + !!opts.force + !!opts.merge)
822 die("git checkout: --ours/--theirs, --force and --merge are incompatible when\nchecking out of the index.");
824 return checkout_paths(source_tree, pathspec, &opts);
827 if (patch_mode)
828 return interactive_checkout(new.name, NULL, &opts);
830 if (opts.new_branch) {
831 struct strbuf buf = STRBUF_INIT;
832 if (strbuf_check_branch_ref(&buf, opts.new_branch))
833 die("git checkout: we do not like '%s' as a branch name.",
834 opts.new_branch);
835 if (!get_sha1(buf.buf, rev))
836 die("git checkout: branch %s already exists", opts.new_branch);
837 strbuf_release(&buf);
840 if (new.name && !new.commit) {
841 die("Cannot switch branch to a non-commit.");
843 if (opts.writeout_stage)
844 die("--ours/--theirs is incompatible with switching branches.");
846 return switch_branches(&opts, &new);