@matheusbsbs / matheus-bagliano / commits / 874cf2a604

stash: apply stash using 'merge_ort_nonrecursive()'

Update 'stash' to use 'merge_ort_nonrecursive()' to apply a stash to the current working tree. When 'git stash apply' was converted from its shell script implementation to a builtin in 8a0fc8d19d (stash: convert apply to builtin, 2019-02-25), 'merge_recursive_generic()' was used to merge a stash into the working tree as part of 'git stash (apply|pop)'. However, with the single merge base used in 'do_apply_stash()', the commit wrapping done by 'merge_recursive_generic()' is not only unnecessary, but misleading (the *real* merge base is labeled "constructed merge base"). Therefore, a non-recursive merge of the working tree, stashed tree, and stash base tree is more appropriate. There are two options for a non-recursive merge-then-update-worktree function: 'merge_trees()' and 'merge_ort_nonrecursive()'. Use 'merge_ort_nonrecursive()' to align with the default merge strategy used by 'git merge' (6a5fb96672 (Change default merge backend from recursive to ort, 2021-08-04)) and, because merge-ort does not operate in-place on the index, avoid unnecessary index expansion. Update tests in 't1092' verifying index expansion for 'git stash' accordingly. Signed-off-by: Victoria Dye <vdye@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Victoria Dye committed May 10, 2022 at 23:32 UTC 874cf2a6044462ddba7162730557354a107c3a6d

2 files changed +26 -8

builtin/stash.c

+24 -6

@@ -7,6 +7,7 @@

7 #include "cache-tree.h"

8 #include "unpack-trees.h"

9 #include "merge-recursive.h"

10 +#include "merge-ort-wrappers.h"

11 #include "strvec.h"

12 #include "run-command.h"

13 #include "dir.h"

@@ -492,13 +493,13 @@ static void unstage_changes_unless_new(struct object_id *orig_tree)

493 static int do_apply_stash(const char *prefix, struct stash_info *info,

494 int index, int quiet)

495 {

495 - int ret;

496 + int clean, ret;

497 int has_index = index;

498 struct merge_options o;

499 struct object_id c_tree;

500 struct object_id index_tree;

500 - struct commit *result;

501 - const struct object_id *bases[1];

501 + struct tree *head, *merge, *merge_base;

502 + struct lock_file lock = LOCK_INIT;

503

504 read_cache_preload(NULL);

505 if (refresh_and_write_cache(REFRESH_QUIET, 0, 0))

@@ -541,6 +542,7 @@ static int do_apply_stash(const char *prefix, struct stash_info *info,

542

543 o.branch1 = "Updated upstream";

544 o.branch2 = "Stashed changes";

545 + o.ancestor = "Stash base";

546

547 if (oideq(&info->b_tree, &c_tree))

548 o.branch1 = "Version stash was based on";

@@ -551,10 +553,26 @@ static int do_apply_stash(const char *prefix, struct stash_info *info,

553 if (o.verbosity >= 3)

554 printf_ln(_("Merging %s with %s"), o.branch1, o.branch2);

555

554 - bases[0] = &info->b_tree;

556 + head = lookup_tree(o.repo, &c_tree);

557 + merge = lookup_tree(o.repo, &info->w_tree);

558 + merge_base = lookup_tree(o.repo, &info->b_tree);

559 +

560 + repo_hold_locked_index(o.repo, &lock, LOCK_DIE_ON_ERROR);

561 + clean = merge_ort_nonrecursive(&o, head, merge, merge_base);

562 +

563 + /*

564 + * If 'clean' >= 0, reverse the value for 'ret' so 'ret' is 0 when the

565 + * merge was clean, and nonzero if the merge was unclean or encountered

566 + * an error.

567 + */

568 + ret = clean >= 0 ? !clean : clean;

569 +

570 + if (ret < 0)

571 + rollback_lock_file(&lock);

572 + else if (write_locked_index(o.repo->index, &lock,

573 + COMMIT_LOCK | SKIP_IF_UNCHANGED))

574 + ret = error(_("could not write index"));

575

556 - ret = merge_recursive_generic(&o, &c_tree, &info->w_tree, 1, bases,

557 - &result);

576 if (ret) {

577 rerere(0);

578

t/t1092-sparse-checkout-compatibility.sh

+2 -2

@@ -1385,7 +1385,7 @@ test_expect_success 'sparse-index is not expanded: stash' '

1385 ensure_not_expanded stash &&

1386 ensure_not_expanded stash list &&

1387 ensure_not_expanded stash show stash@{0} &&

1388 - ! ensure_not_expanded stash apply stash@{0} &&

1388 + ensure_not_expanded stash apply stash@{0} &&

1389 ensure_not_expanded stash drop stash@{0} &&

1390

1391 echo >>sparse-index/deep/new &&

@@ -1399,7 +1399,7 @@ test_expect_success 'sparse-index is not expanded: stash' '

1399 oid=$(git -C sparse-index stash create) &&

1400 ensure_not_expanded stash store -m "test" $oid &&

1401 ensure_not_expanded reset --hard &&

1402 - ! ensure_not_expanded stash pop

1402 + ensure_not_expanded stash pop

1403 '

1404

1405 test_expect_success 'sparse index is not expanded: diff' '