checkout: Fix "initial checkout" detection

Earlier commit 5521883 (checkout: do not lose staged removal, 2008-09-07) tightened the rule to prevent switching branches from losing local changes, so that staged removal of paths can be protected, while attempting to keep a loophole to still allow a special case of switching out of an un-checked-out state. However, the loophole was made a bit too tight, and did not allow switching from one branch (in an un-checked-out state) to check out another branch. The change to builtin-checkout.c in this commit loosens it to allow this, by not insisting the original commit and the new commit to be the same. It also introduces a new function, is_index_unborn (and an associated macro, is_cache_unborn), to check if the repository is truly in an un-checked-out state more reliably, by making sure that $GIT_INDEX_FILE did not exist when populating the in-core index structure. A few places the earlier commit 5521883 added the check for the initial checkout condition are updated to use this function. Signed-off-by: Junio C Hamano <gitster@pobox.com>

Junio C Hamano committed Nov 12, 2008 at 11:52 UTC fa7b3c2f752a10a5dca9989d4a1c4b93ffa7f943

4 files changed +9 -3

builtin-checkout.c

+1 -2

@@ -269,8 +269,7 @@ static int merge_working_tree(struct checkout_opts *opts,

269 }

270

271 /* 2-way merge to the new branch */

272 - topts.initial_checkout = (!active_nr &&

273 - (old->commit == new->commit));

272 + topts.initial_checkout = is_cache_unborn();

273 topts.update = 1;

274 topts.merge = 1;

275 topts.gently = opts->merge;

builtin-read-tree.c

+1 -1

@@ -206,7 +206,7 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)

206 break;

207 case 2:

208 opts.fn = twoway_merge;

209 - opts.initial_checkout = !active_nr;

209 + opts.initial_checkout = is_cache_unborn();

210 break;

211 case 3:

212 default:

cache.h

@@ -255,6 +255,7 @@ static inline void remove_name_hash(struct cache_entry *ce)

255

256 #define read_cache() read_index(&the_index)

257 #define read_cache_from(path) read_index_from(&the_index, (path))

258 +#define is_cache_unborn() is_index_unborn(&the_index)

259 #define read_cache_unmerged() read_index_unmerged(&the_index)

260 #define write_cache(newfd, cache, entries) write_index(&the_index, (newfd))

261 #define discard_cache() discard_index(&the_index)

@@ -360,6 +361,7 @@ extern int init_db(const char *template_dir, unsigned int flags);

361 /* Initialize and use the cache information */

362 extern int read_index(struct index_state *);

363 extern int read_index_from(struct index_state *, const char *path);

364 +extern int is_index_unborn(struct index_state *);

365 extern int read_index_unmerged(struct index_state *);

366 extern int write_index(const struct index_state *, int newfd);

367 extern int discard_index(struct index_state *);

read-cache.c

@@ -1239,6 +1239,11 @@ unmap:

1239 die("index file corrupt");

1240 }

1241

1242 +int is_index_unborn(struct index_state *istate)

1243 +{

1244 + return (!istate->cache_nr && !istate->alloc && !istate->timestamp);

1245 +}

1246 +

1247 int discard_index(struct index_state *istate)

1248 {

1249 istate->cache_nr = 0;