@matheusbsbs / matheus-bagliano / commits / 7497039241

read-tree: narrow scope of index expansion for '--prefix'

When 'git read-tree' is provided with a prefix, expand the index only if the prefix is equivalent to a sparse directory or contained within one. If the index is not expanded in these cases, 'ce_in_traverse_path' will indicate that the relevant sparse directory is not in the prefix/traverse path, skipping past it and not unpacking the appropriate tree(s). If the prefix is in-cone, its sparse subdirectories (if any) will be traversed correctly without index expansion. The behavior of 'git read-tree' with prefixes 1) inside of cone, 2) equal to a sparse directory, and 3) inside a sparse directory are all tested as part of the 't/t1092-sparse-checkout-compatibility.sh' test 'read-tree --prefix', ensuring that the sparse index case works the way it did prior to this change as well as matching non-sparse index sparse-checkout. Helped-by: Elijah Newren <newren@gmail.com> Signed-off-by: Victoria Dye <vdye@github.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Victoria Dye committed Mar 1, 2022 at 20:24 UTC 749703924121b9eb2750b4313b2c769113c8b310
3 files changed +46 -3
builtin/read-tree.c
+1 -2
index 0a52cab775..ec6d038242 100644 --- a/builtin/read-tree.c +++ b/builtin/read-tree.c @@ -217,8 +217,7 @@ int cmd_read_tree(int argc, const char **argv, const char *cmd_prefix) if (opts.merge && !opts.index_only) setup_work_tree(); - /* TODO: audit sparse index behavior in unpack_trees */ - if (opts.skip_sparse_checkout || opts.prefix) + if (opts.skip_sparse_checkout) ensure_full_index(&the_index); if (opts.merge) {
t/t1092-sparse-checkout-compatibility.sh
+7 -1
index 86241b01a5..d98558f323 100755 --- a/t/t1092-sparse-checkout-compatibility.sh +++ b/t/t1092-sparse-checkout-compatibility.sh @@ -1417,7 +1417,13 @@ test_expect_success 'sparse index is not expanded: read-tree' ' do ensure_not_expanded read-tree -mu $MERGE_TREES && ensure_not_expanded reset --hard || return 1 - done + done && + + rm -rf sparse-index/deep/deeper2 && + ensure_not_expanded add . && + ensure_not_expanded commit -m "test" && + + ensure_not_expanded read-tree --prefix=deep/deeper2 -u deepest ' test_expect_success 'ls-files' '
unpack-trees.c
+38
index 360844bda3..f3667d85ec 100644 --- a/unpack-trees.c +++ b/unpack-trees.c @@ -1693,6 +1693,41 @@ static void populate_from_existing_patterns(struct unpack_trees_options *o, o->pl = pl; } +static void update_sparsity_for_prefix(const char *prefix, + struct index_state *istate) +{ + int prefix_len = strlen(prefix); + struct strbuf ce_prefix = STRBUF_INIT; + + if (!istate->sparse_index) + return; + + while (prefix_len > 0 && prefix[prefix_len - 1] == '/') + prefix_len--; + + if (prefix_len <= 0) + BUG("Invalid prefix passed to update_sparsity_for_prefix"); + + strbuf_grow(&ce_prefix, prefix_len + 1); + strbuf_add(&ce_prefix, prefix, prefix_len); + strbuf_addch(&ce_prefix, '/'); + + /* + * If the prefix points to a sparse directory or a path inside a sparse + * directory, the index should be expanded. This is accomplished in one + * of two ways: + * - if the prefix is inside a sparse directory, it will be expanded by + * the 'ensure_full_index(...)' call in 'index_name_pos(...)'. + * - if the prefix matches an existing sparse directory entry, + * 'index_name_pos(...)' will return its index position, triggering + * the 'ensure_full_index(...)' below. + */ + if (!path_in_cone_mode_sparse_checkout(ce_prefix.buf, istate) && + index_name_pos(istate, ce_prefix.buf, ce_prefix.len) >= 0) + ensure_full_index(istate); + + strbuf_release(&ce_prefix); +} static int verify_absent(const struct cache_entry *, enum unpack_trees_error_types, @@ -1739,6 +1774,9 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options setup_standard_excludes(o->dir); } + if (o->prefix) + update_sparsity_for_prefix(o->prefix, o->src_index); + if (!core_apply_sparse_checkout || !o->update) o->skip_sparse_checkout = 1; if (!o->skip_sparse_checkout && !o->pl) {