Build in checkout
The only differences in behavior should be: - git checkout -m with non-trivial merging won't print out merge-recursive messages (see the change in t7201-co.sh) - git checkout -- paths... will give a sensible error message if HEAD is invalid as a commit. - some intermediate states which were written to disk in the shell version (in particular, index states) are only kept in memory in this version, and therefore these can no longer be revealed by later write operations becoming impossible. - when we change branches, we discard MERGE_MSG, SQUASH_MSG, and rr-cache/MERGE_RR, like reset always has. I'm not 100% sure I got the merge recursive setup exactly right; the base for a non-trivial merge in the shell code doesn't seem theoretically justified to me, but I tried to match it anyway, and the tests all pass this way. Other than these items, the results should be identical to the shell version, so far as I can tell. [jc: squashed lock-file fix from Dscho in] Signed-off-by: Daniel Barkalow <barkalow@iabervon.org> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Daniel Barkalow committed
Feb 7, 2008 at 11:40 UTC
782c2d65c24066a5d83453efb52763bc34c10f81
6 files changed
+481
-8
Makefile
+2
-1
@@ -217,7 +217,7 @@ BASIC_CFLAGS =
217
BASIC_LDFLAGS =
218
219
SCRIPT_SH = \
220
- git-bisect.sh git-checkout.sh \
220
+ git-bisect.sh \
221
git-clone.sh \
222
git-merge-one-file.sh git-mergetool.sh git-parse-remote.sh \
223
git-pull.sh git-rebase.sh git-rebase--interactive.sh \
@@ -329,6 +329,7 @@ BUILTIN_OBJS = \
329
builtin-bundle.o \
330
builtin-cat-file.o \
331
builtin-check-attr.o \
332
+ builtin-checkout.o \
333
builtin-checkout-index.o \
334
builtin-check-ref-format.o \
335
builtin-clean.o \
builtin-checkout.c
new
+477
@@ -0,0 +1,477 @@
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 "unpack-trees.h"
9
+#include "dir.h"
10
+#include "run-command.h"
11
+#include "merge-recursive.h"
12
+#include "branch.h"
13
+#include "diff.h"
14
+#include "revision.h"
15
+
16
+static const char * const checkout_usage[] = {
17
+ "git checkout [options] <branch>",
18
+ "git checkout [options] [<branch>] -- <file>...",
19
+ NULL,
20
+};
21
+
22
+static int post_checkout_hook(struct commit *old, struct commit *new,
23
+ int changed)
24
+{
25
+ struct child_process proc;
26
+ const char *name = git_path("hooks/post-checkout");
27
+ const char *argv[5];
28
+
29
+ if (access(name, X_OK) < 0)
30
+ return 0;
31
+
32
+ memset(&proc, 0, sizeof(proc));
33
+ argv[0] = name;
34
+ argv[1] = xstrdup(sha1_to_hex(old->object.sha1));
35
+ argv[2] = xstrdup(sha1_to_hex(new->object.sha1));
36
+ argv[3] = changed ? "1" : "0";
37
+ argv[4] = NULL;
38
+ proc.argv = argv;
39
+ proc.no_stdin = 1;
40
+ proc.stdout_to_stderr = 1;
41
+ return run_command(&proc);
42
+}
43
+
44
+static int update_some(const unsigned char *sha1, const char *base, int baselen,
45
+ const char *pathname, unsigned mode, int stage)
46
+{
47
+ int len;
48
+ struct cache_entry *ce;
49
+
50
+ if (S_ISGITLINK(mode))
51
+ return 0;
52
+
53
+ if (S_ISDIR(mode))
54
+ return READ_TREE_RECURSIVE;
55
+
56
+ len = baselen + strlen(pathname);
57
+ ce = xcalloc(1, cache_entry_size(len));
58
+ hashcpy(ce->sha1, sha1);
59
+ memcpy(ce->name, base, baselen);
60
+ memcpy(ce->name + baselen, pathname, len - baselen);
61
+ ce->ce_flags = create_ce_flags(len, 0);
62
+ ce->ce_mode = create_ce_mode(mode);
63
+ add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
64
+ return 0;
65
+}
66
+
67
+static int read_tree_some(struct tree *tree, const char **pathspec)
68
+{
69
+ int newfd;
70
+ struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
71
+ newfd = hold_locked_index(lock_file, 1);
72
+ read_cache();
73
+
74
+ read_tree_recursive(tree, "", 0, 0, pathspec, update_some);
75
+
76
+ if (write_cache(newfd, active_cache, active_nr) ||
77
+ commit_locked_index(lock_file))
78
+ die("unable to write new index file");
79
+
80
+ /* update the index with the given tree's info
81
+ * for all args, expanding wildcards, and exit
82
+ * with any non-zero return code.
83
+ */
84
+ return 0;
85
+}
86
+
87
+static int checkout_paths(const char **pathspec)
88
+{
89
+ int pos;
90
+ struct checkout state;
91
+ static char *ps_matched;
92
+ unsigned char rev[20];
93
+ int flag;
94
+ struct commit *head;
95
+
96
+ for (pos = 0; pathspec[pos]; pos++)
97
+ ;
98
+ ps_matched = xcalloc(1, pos);
99
+
100
+ for (pos = 0; pos < active_nr; pos++) {
101
+ struct cache_entry *ce = active_cache[pos];
102
+ pathspec_match(pathspec, ps_matched, ce->name, 0);
103
+ }
104
+
105
+ if (report_path_error(ps_matched, pathspec, 0))
106
+ return 1;
107
+
108
+ memset(&state, 0, sizeof(state));
109
+ state.force = 1;
110
+ state.refresh_cache = 1;
111
+ for (pos = 0; pos < active_nr; pos++) {
112
+ struct cache_entry *ce = active_cache[pos];
113
+ if (pathspec_match(pathspec, NULL, ce->name, 0)) {
114
+ checkout_entry(ce, &state, NULL);
115
+ }
116
+ }
117
+
118
+ resolve_ref("HEAD", rev, 0, &flag);
119
+ head = lookup_commit_reference_gently(rev, 1);
120
+
121
+ return post_checkout_hook(head, head, 0);
122
+}
123
+
124
+static void show_local_changes(struct object *head)
125
+{
126
+ struct rev_info rev;
127
+ /* I think we want full paths, even if we're in a subdirectory. */
128
+ init_revisions(&rev, NULL);
129
+ rev.abbrev = 0;
130
+ rev.diffopt.output_format |= DIFF_FORMAT_NAME_STATUS;
131
+ add_pending_object(&rev, head, NULL);
132
+ run_diff_index(&rev, 0);
133
+}
134
+
135
+static void describe_detached_head(char *msg, struct commit *commit)
136
+{
137
+ struct strbuf sb;
138
+ strbuf_init(&sb, 0);
139
+ parse_commit(commit);
140
+ pretty_print_commit(CMIT_FMT_ONELINE, commit, &sb, 0, "", "", 0, 0);
141
+ fprintf(stderr, "%s %s... %s\n", msg,
142
+ find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV), sb.buf);
143
+ strbuf_release(&sb);
144
+}
145
+
146
+static int reset_to_new(struct tree *tree, int quiet)
147
+{
148
+ struct unpack_trees_options opts;
149
+ struct tree_desc tree_desc;
150
+ memset(&opts, 0, sizeof(opts));
151
+ opts.head_idx = -1;
152
+ opts.update = 1;
153
+ opts.reset = 1;
154
+ opts.merge = 1;
155
+ opts.fn = oneway_merge;
156
+ opts.verbose_update = !quiet;
157
+ parse_tree(tree);
158
+ init_tree_desc(&tree_desc, tree->buffer, tree->size);
159
+ if (unpack_trees(1, &tree_desc, &opts))
160
+ return 128;
161
+ return 0;
162
+}
163
+
164
+static void reset_clean_to_new(struct tree *tree, int quiet)
165
+{
166
+ struct unpack_trees_options opts;
167
+ struct tree_desc tree_desc;
168
+ memset(&opts, 0, sizeof(opts));
169
+ opts.head_idx = -1;
170
+ opts.skip_unmerged = 1;
171
+ opts.reset = 1;
172
+ opts.merge = 1;
173
+ opts.fn = oneway_merge;
174
+ opts.verbose_update = !quiet;
175
+ parse_tree(tree);
176
+ init_tree_desc(&tree_desc, tree->buffer, tree->size);
177
+ if (unpack_trees(1, &tree_desc, &opts))
178
+ exit(128);
179
+}
180
+
181
+struct checkout_opts {
182
+ int quiet;
183
+ int merge;
184
+ int force;
185
+
186
+ char *new_branch;
187
+ int new_branch_log;
188
+ int track;
189
+};
190
+
191
+struct branch_info {
192
+ const char *name; /* The short name used */
193
+ const char *path; /* The full name of a real branch */
194
+ struct commit *commit; /* The named commit */
195
+};
196
+
197
+static void setup_branch_path(struct branch_info *branch)
198
+{
199
+ struct strbuf buf;
200
+ strbuf_init(&buf, 0);
201
+ strbuf_addstr(&buf, "refs/heads/");
202
+ strbuf_addstr(&buf, branch->name);
203
+ branch->path = strbuf_detach(&buf, NULL);
204
+}
205
+
206
+static int merge_working_tree(struct checkout_opts *opts,
207
+ struct branch_info *old, struct branch_info *new,
208
+ const char *prefix)
209
+{
210
+ int ret;
211
+ struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
212
+ int newfd = hold_locked_index(lock_file, 1);
213
+ read_cache();
214
+
215
+ if (opts->force) {
216
+ ret = reset_to_new(new->commit->tree, opts->quiet);
217
+ if (ret)
218
+ return ret;
219
+ } else {
220
+ struct tree_desc trees[2];
221
+ struct tree *tree;
222
+ struct unpack_trees_options topts;
223
+ memset(&topts, 0, sizeof(topts));
224
+ topts.head_idx = -1;
225
+
226
+ refresh_cache(REFRESH_QUIET);
227
+
228
+ if (unmerged_cache()) {
229
+ ret = opts->merge ? -1 :
230
+ error("you need to resolve your current index first");
231
+ } else {
232
+ topts.update = 1;
233
+ topts.merge = 1;
234
+ topts.gently = opts->merge;
235
+ topts.fn = twoway_merge;
236
+ topts.dir = xcalloc(1, sizeof(*topts.dir));
237
+ topts.dir->show_ignored = 1;
238
+ topts.dir->exclude_per_dir = ".gitignore";
239
+ topts.prefix = prefix;
240
+ tree = parse_tree_indirect(old->commit->object.sha1);
241
+ init_tree_desc(&trees[0], tree->buffer, tree->size);
242
+ tree = parse_tree_indirect(new->commit->object.sha1);
243
+ init_tree_desc(&trees[1], tree->buffer, tree->size);
244
+ ret = unpack_trees(2, trees, &topts);
245
+ }
246
+ if (ret) {
247
+ /*
248
+ * Unpack couldn't do a trivial merge; either
249
+ * give up or do a real merge, depending on
250
+ * whether the merge flag was used.
251
+ */
252
+ struct tree *result;
253
+ struct tree *work;
254
+ if (!opts->merge)
255
+ return 1;
256
+ parse_commit(old->commit);
257
+
258
+ /* Do more real merge */
259
+
260
+ /*
261
+ * We update the index fully, then write the
262
+ * tree from the index, then merge the new
263
+ * branch with the current tree, with the old
264
+ * branch as the base. Then we reset the index
265
+ * (but not the working tree) to the new
266
+ * branch, leaving the working tree as the
267
+ * merged version, but skipping unmerged
268
+ * entries in the index.
269
+ */
270
+
271
+ add_files_to_cache(0, NULL, NULL);
272
+ work = write_tree_from_memory();
273
+
274
+ ret = reset_to_new(new->commit->tree, opts->quiet);
275
+ if (ret)
276
+ return ret;
277
+ merge_trees(new->commit->tree, work, old->commit->tree,
278
+ new->name, "local", &result);
279
+ reset_clean_to_new(new->commit->tree, opts->quiet);
280
+ }
281
+ }
282
+
283
+ if (write_cache(newfd, active_cache, active_nr) ||
284
+ commit_locked_index(lock_file))
285
+ die("unable to write new index file");
286
+
287
+ if (!opts->force)
288
+ show_local_changes(&new->commit->object);
289
+
290
+ return 0;
291
+}
292
+
293
+static void update_refs_for_switch(struct checkout_opts *opts,
294
+ struct branch_info *old,
295
+ struct branch_info *new)
296
+{
297
+ struct strbuf msg;
298
+ const char *old_desc;
299
+ if (opts->new_branch) {
300
+ create_branch(old->name, opts->new_branch, new->name, 0,
301
+ opts->new_branch_log, opts->track);
302
+ new->name = opts->new_branch;
303
+ setup_branch_path(new);
304
+ }
305
+
306
+ strbuf_init(&msg, 0);
307
+ old_desc = old->name;
308
+ if (!old_desc)
309
+ old_desc = sha1_to_hex(old->commit->object.sha1);
310
+ strbuf_addf(&msg, "checkout: moving from %s to %s",
311
+ old_desc, new->name);
312
+
313
+ if (new->path) {
314
+ create_symref("HEAD", new->path, msg.buf);
315
+ if (!opts->quiet) {
316
+ if (old->path && !strcmp(new->path, old->path))
317
+ fprintf(stderr, "Already on \"%s\"\n",
318
+ new->name);
319
+ else
320
+ fprintf(stderr, "Switched to%s branch \"%s\"\n",
321
+ opts->new_branch ? " a new" : "",
322
+ new->name);
323
+ }
324
+ } else if (strcmp(new->name, "HEAD")) {
325
+ update_ref(msg.buf, "HEAD", new->commit->object.sha1, NULL,
326
+ REF_NODEREF, DIE_ON_ERR);
327
+ if (!opts->quiet) {
328
+ if (old->path)
329
+ fprintf(stderr, "Note: moving to \"%s\" which isn't a local branch\nIf you want to create a new branch from this checkout, you may do so\n(now or later) by using -b with the checkout command again. Example:\n git checkout -b <new_branch_name>\n", new->name);
330
+ describe_detached_head("HEAD is now at", new->commit);
331
+ }
332
+ }
333
+ remove_branch_state();
334
+ strbuf_release(&msg);
335
+}
336
+
337
+static int switch_branches(struct checkout_opts *opts,
338
+ struct branch_info *new, const char *prefix)
339
+{
340
+ int ret = 0;
341
+ struct branch_info old;
342
+ unsigned char rev[20];
343
+ int flag;
344
+ memset(&old, 0, sizeof(old));
345
+ old.path = resolve_ref("HEAD", rev, 0, &flag);
346
+ old.commit = lookup_commit_reference_gently(rev, 1);
347
+ if (!(flag & REF_ISSYMREF))
348
+ old.path = NULL;
349
+
350
+ if (old.path && !prefixcmp(old.path, "refs/heads/"))
351
+ old.name = old.path + strlen("refs/heads/");
352
+
353
+ if (!new->name) {
354
+ new->name = "HEAD";
355
+ new->commit = old.commit;
356
+ if (!new->commit)
357
+ die("You are on a branch yet to be born");
358
+ parse_commit(new->commit);
359
+ }
360
+
361
+ /*
362
+ * If the new thing isn't a branch and isn't HEAD and we're
363
+ * not starting a new branch, and we want messages, and we
364
+ * weren't on a branch, and we're moving to a new commit,
365
+ * describe the old commit.
366
+ */
367
+ if (!new->path && strcmp(new->name, "HEAD") && !opts->new_branch &&
368
+ !opts->quiet && !old.path && new->commit != old.commit)
369
+ describe_detached_head("Previous HEAD position was", old.commit);
370
+
371
+ if (!old.commit) {
372
+ if (!opts->quiet) {
373
+ fprintf(stderr, "warning: You appear to be on a branch yet to be born.\n");
374
+ fprintf(stderr, "warning: Forcing checkout of %s.\n", new->name);
375
+ }
376
+ opts->force = 1;
377
+ }
378
+
379
+ ret = merge_working_tree(opts, &old, new, prefix);
380
+ if (ret)
381
+ return ret;
382
+
383
+ update_refs_for_switch(opts, &old, new);
384
+
385
+ return post_checkout_hook(old.commit, new->commit, 1);
386
+}
387
+
388
+static int branch_track = 0;
389
+
390
+static int git_checkout_config(const char *var, const char *value)
391
+{
392
+ if (!strcmp(var, "branch.autosetupmerge"))
393
+ branch_track = git_config_bool(var, value);
394
+
395
+ return git_default_config(var, value);
396
+}
397
+
398
+int cmd_checkout(int argc, const char **argv, const char *prefix)
399
+{
400
+ struct checkout_opts opts;
401
+ unsigned char rev[20];
402
+ const char *arg;
403
+ struct branch_info new;
404
+ struct tree *source_tree = NULL;
405
+ struct option options[] = {
406
+ OPT__QUIET(&opts.quiet),
407
+ OPT_STRING('b', NULL, &opts.new_branch, "new branch", "branch"),
408
+ OPT_BOOLEAN('l', NULL, &opts.new_branch_log, "log for new branch"),
409
+ OPT_BOOLEAN( 0 , "track", &opts.track, "track"),
410
+ OPT_BOOLEAN('f', NULL, &opts.force, "force"),
411
+ OPT_BOOLEAN('m', NULL, &opts.merge, "merge"),
412
+ };
413
+
414
+ memset(&opts, 0, sizeof(opts));
415
+ memset(&new, 0, sizeof(new));
416
+
417
+ git_config(git_checkout_config);
418
+
419
+ opts.track = branch_track;
420
+
421
+ argc = parse_options(argc, argv, options, checkout_usage, 0);
422
+ if (argc) {
423
+ arg = argv[0];
424
+ if (get_sha1(arg, rev))
425
+ ;
426
+ else if ((new.commit = lookup_commit_reference_gently(rev, 1))) {
427
+ new.name = arg;
428
+ setup_branch_path(&new);
429
+ if (resolve_ref(new.path, rev, 1, NULL))
430
+ new.commit = lookup_commit_reference(rev);
431
+ else
432
+ new.path = NULL;
433
+ parse_commit(new.commit);
434
+ source_tree = new.commit->tree;
435
+ argv++;
436
+ argc--;
437
+ } else if ((source_tree = parse_tree_indirect(rev))) {
438
+ argv++;
439
+ argc--;
440
+ }
441
+ }
442
+
443
+ if (argc && !strcmp(argv[0], "--")) {
444
+ argv++;
445
+ argc--;
446
+ }
447
+
448
+ if (!opts.new_branch && (opts.track != branch_track))
449
+ die("git checkout: --track and --no-track require -b");
450
+
451
+ if (opts.force && opts.merge)
452
+ die("git checkout: -f and -m are incompatible");
453
+
454
+ if (argc) {
455
+ const char **pathspec = get_pathspec(prefix, argv);
456
+ /* Checkout paths */
457
+ if (opts.new_branch || opts.force || opts.merge) {
458
+ if (argc == 1) {
459
+ die("git checkout: updating paths is incompatible with switching branches/forcing\nDid you intend to checkout '%s' which can not be resolved as commit?", argv[0]);
460
+ } else {
461
+ die("git checkout: updating paths is incompatible with switching branches/forcing");
462
+ }
463
+ }
464
+
465
+ if (source_tree)
466
+ read_tree_some(source_tree, pathspec);
467
+ else
468
+ read_cache();
469
+ return checkout_paths(pathspec);
470
+ }
471
+
472
+ if (new.name && !new.commit) {
473
+ die("Cannot switch branch to a non-commit.");
474
+ }
475
+
476
+ return switch_branches(&opts, &new, prefix);
477
+}
builtin.h
+1
@@ -19,6 +19,7 @@ extern int cmd_blame(int argc, const char **argv, const char *prefix);
19
extern int cmd_branch(int argc, const char **argv, const char *prefix);
20
extern int cmd_bundle(int argc, const char **argv, const char *prefix);
21
extern int cmd_cat_file(int argc, const char **argv, const char *prefix);
22
+extern int cmd_checkout(int argc, const char **argv, const char *prefix);
23
extern int cmd_checkout_index(int argc, const char **argv, const char *prefix);
24
extern int cmd_check_attr(int argc, const char **argv, const char *prefix);
25
extern int cmd_check_ref_format(int argc, const char **argv, const char *prefix);
contrib/examples/git-checkout.sh
renamed
git.c
+1
@@ -287,6 +287,7 @@ static void handle_internal_command(int argc, const char **argv)
287
{ "branch", cmd_branch, RUN_SETUP },
288
{ "bundle", cmd_bundle },
289
{ "cat-file", cmd_cat_file, RUN_SETUP },
290
+ { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
291
{ "checkout-index", cmd_checkout_index,
292
RUN_SETUP | NEED_WORK_TREE},
293
{ "check-ref-format", cmd_check_ref_format },
t/t7201-co.sh
-7
@@ -103,13 +103,6 @@ test_expect_success "checkout -m with dirty tree" '
103
test "$(git symbolic-ref HEAD)" = "refs/heads/side" &&
104
105
(cat >expect.messages <<EOF
106
-Merging side with local
107
-Merging:
108
-ab76817 Side M one, D two, A three
109
-virtual local
110
-found 1 common ancestor(s):
111
-7329388 Initial A one, A two
112
-Auto-merged one
106
M one
107
EOF
108
) &&