reset: make --mixed sparse-aware
Remove the `ensure_full_index` guard on `read_from_tree` and update `git reset --mixed` to ensure it can use sparse directory index entries wherever possible. Sparse directory entries are reset using `diff_tree_oid`, which requires `change` and `add_remove` functions to process the internal contents of the sparse directory. The `recursive` diff option handles cases in which `reset --mixed` must diff/merge files that are nested multiple levels deep in a sparse directory. The use of pathspecs with `git reset --mixed` introduces scenarios in which internal contents of sparse directories may be matched by the pathspec. In order to reset *all* files in the repo that may match the pathspec, the following conditions on the pathspec require index expansion before performing the reset: * "magic" pathspecs * wildcard pathspecs that do not match only in-cone files or entire sparse directories * literal pathspecs matching something outside the sparse checkout definition 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
Nov 29, 2021 at 15:52 UTC
4d1cfc1351ffec47bba1318e9cd1ed13c5182951
2 files changed
+102
-2
builtin/reset.c
+85
-2
@@ -148,7 +148,9 @@ static void update_index_from_diff(struct diff_queue_struct *q,
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* If the file 1) corresponds to an existing index entry with
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* skip-worktree set, or 2) does not exist in the index but is
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* outside the sparse checkout definition, add a skip-worktree bit
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- * to the new index entry.
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+ * to the new index entry. Note that a sparse index will be expanded
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+ * if this entry is outside the sparse cone - this is necessary
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+ * to properly construct the reset sparse directory.
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*/
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pos = cache_name_pos(one->path, strlen(one->path));
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if ((pos >= 0 && ce_skip_worktree(active_cache[pos])) ||
@@ -166,6 +168,82 @@ static void update_index_from_diff(struct diff_queue_struct *q,
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}
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}
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+static int pathspec_needs_expanded_index(const struct pathspec *pathspec)
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+{
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+ unsigned int i, pos;
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+ int res = 0;
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+ char *skip_worktree_seen = NULL;
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+
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+ /*
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+ * When using a magic pathspec, assume for the sake of simplicity that
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+ * the index needs to be expanded to match all matchable files.
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+ */
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+ if (pathspec->magic)
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+ return 1;
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+
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+ for (i = 0; i < pathspec->nr; i++) {
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+ struct pathspec_item item = pathspec->items[i];
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+
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+ /*
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+ * If the pathspec item has a wildcard, the index should be expanded
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+ * if the pathspec has the possibility of matching a subset of entries inside
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+ * of a sparse directory (but not the entire directory).
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+ *
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+ * If the pathspec item is a literal path, the index only needs to be expanded
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+ * if a) the pathspec isn't in the sparse checkout cone (to make sure we don't
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+ * expand for in-cone files) and b) it doesn't match any sparse directories
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+ * (since we can reset whole sparse directories without expanding them).
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+ */
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+ if (item.nowildcard_len < item.len) {
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+ /*
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+ * Special case: if the pattern is a path inside the cone
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+ * followed by only wildcards, the pattern cannot match
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+ * partial sparse directories, so we don't expand the index.
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+ */
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+ if (path_in_cone_mode_sparse_checkout(item.original, &the_index) &&
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+ strspn(item.original + item.nowildcard_len, "*") == item.len - item.nowildcard_len)
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+ continue;
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+
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+ for (pos = 0; pos < active_nr; pos++) {
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+ struct cache_entry *ce = active_cache[pos];
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+
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+ if (!S_ISSPARSEDIR(ce->ce_mode))
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+ continue;
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+
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+ /*
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+ * If the pre-wildcard length is longer than the sparse
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+ * directory name and the sparse directory is the first
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+ * component of the pathspec, need to expand the index.
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+ */
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+ if (item.nowildcard_len > ce_namelen(ce) &&
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+ !strncmp(item.original, ce->name, ce_namelen(ce))) {
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+ res = 1;
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+ break;
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+ }
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+
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+ /*
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+ * If the pre-wildcard length is shorter than the sparse
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+ * directory and the pathspec does not match the whole
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+ * directory, need to expand the index.
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+ */
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+ if (!strncmp(item.original, ce->name, item.nowildcard_len) &&
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+ wildmatch(item.original, ce->name, 0)) {
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+ res = 1;
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+ break;
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+ }
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+ }
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+ } else if (!path_in_cone_mode_sparse_checkout(item.original, &the_index) &&
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+ !matches_skip_worktree(pathspec, i, &skip_worktree_seen))
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+ res = 1;
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+
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+ if (res > 0)
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+ break;
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+ }
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+
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+ free(skip_worktree_seen);
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+ return res;
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+}
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+
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static int read_from_tree(const struct pathspec *pathspec,
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struct object_id *tree_oid,
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int intent_to_add)
@@ -178,9 +256,14 @@ static int read_from_tree(const struct pathspec *pathspec,
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opt.format_callback = update_index_from_diff;
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opt.format_callback_data = &intent_to_add;
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opt.flags.override_submodule_config = 1;
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+ opt.flags.recursive = 1;
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opt.repo = the_repository;
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+ opt.change = diff_change;
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+ opt.add_remove = diff_addremove;
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+
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+ if (pathspec->nr && the_index.sparse_index && pathspec_needs_expanded_index(pathspec))
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+ ensure_full_index(&the_index);
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- ensure_full_index(&the_index);
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if (do_diff_cache(tree_oid, &opt))
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return 1;
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diffcore_std(&opt);
t/t1092-sparse-checkout-compatibility.sh
+17
@@ -795,11 +795,28 @@ test_expect_success 'sparse-index is not expanded' '
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ensure_not_expanded reset --hard $ref || return 1
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done &&
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+ ensure_not_expanded reset --mixed base &&
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ensure_not_expanded reset --hard update-deep &&
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ensure_not_expanded reset --keep base &&
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ensure_not_expanded reset --merge update-deep &&
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ensure_not_expanded reset --hard &&
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+ ensure_not_expanded reset base -- deep/a &&
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+ ensure_not_expanded reset base -- nonexistent-file &&
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+ ensure_not_expanded reset deepest -- deep &&
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+
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+ # Although folder1 is outside the sparse definition, it exists as a
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+ # directory entry in the index, so the pathspec will not force the
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+ # index to be expanded.
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+ ensure_not_expanded reset deepest -- folder1 &&
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+ ensure_not_expanded reset deepest -- folder1/ &&
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+
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+ # Wildcard identifies only in-cone files, no index expansion
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+ ensure_not_expanded reset deepest -- deep/\* &&
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+
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+ # Wildcard identifies only full sparse directories, no index expansion
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+ ensure_not_expanded reset deepest -- folder\* &&
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+
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ensure_not_expanded checkout -f update-deep &&
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test_config -C sparse-index pull.twohead ort &&
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(