From: Victoria Dye <vdye@xxxxxxxxxx>
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@xxxxxxxxx>
Signed-off-by: Victoria Dye <vdye@xxxxxxxxxx>
---
builtin/read-tree.c | 3 +-
t/t1092-sparse-checkout-compatibility.sh | 8 ++++-
unpack-trees.c | 38 ++++++++++++++++++++++++
3 files changed, 46 insertions(+), 3 deletions(-)
diff --git a/builtin/read-tree.c b/builtin/read-tree.c
index 0a52cab7752..ec6d038242a 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) {
diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index 86241b01a59..d98558f3238 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' '
diff --git a/unpack-trees.c b/unpack-trees.c
index 360844bda3a..f3667d85ec5 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) {
--
gitgitgadget
