read-tree: make three-way merge sparse-aware
Enable use of 'merged_sparse_dir' in 'threeway_merge'. As with two-way merge, the contents of each conflicted sparse directory are merged without referencing the index, avoiding sparse index expansion. As with two-way merge, the 't/t1092-sparse-checkout-compatibility.sh' test 'read-tree --merge with edit/edit conflicts in sparse directories' confirms that three-way merges with edit/edit changes (both with and without conflicts) inside a sparse directory result in the correct index state or error message. To ensure the index is not unnecessarily expanded, add three-way merge cases to 'sparse index is not expanded: read-tree'. 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
f27c170f645e6b8ed642c49c503964893ee26a4f
3 files changed
+29
-14
builtin/read-tree.c
-5
@@ -234,11 +234,6 @@ int cmd_read_tree(int argc, const char **argv, const char *cmd_prefix)
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break;
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case 3:
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default:
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- /*
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- * TODO: update threeway_merge to handle edit/edit conflicts in
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- * sparse directories.
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- */
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- ensure_full_index(&the_index);
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opts.fn = threeway_merge;
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break;
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}
t/t1092-sparse-checkout-compatibility.sh
+3
-1
@@ -1413,7 +1413,9 @@ test_expect_success 'sparse index is not expanded: read-tree' '
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init_repos &&
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ensure_not_expanded checkout -b test-branch update-folder1 &&
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- for MERGE_TREES in "base update-folder2" \
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+ for MERGE_TREES in "base HEAD update-folder2" \
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+ "base HEAD rename-base" \
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+ "base update-folder2" \
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"base rename-base" \
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"update-folder2"
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do
unpack-trees.c
+26
-8
@@ -2643,16 +2643,24 @@ int threeway_merge(const struct cache_entry * const *stages,
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*/
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/* #14, #14ALT, #2ALT */
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if (remote && !df_conflict_head && head_match && !remote_match) {
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- if (index && !same(index, remote) && !same(index, head))
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- return reject_merge(index, o);
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+ if (index && !same(index, remote) && !same(index, head)) {
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+ if (S_ISSPARSEDIR(index->ce_mode))
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+ return merged_sparse_dir(stages, 4, o);
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+ else
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+ return reject_merge(index, o);
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+ }
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return merged_entry(remote, index, o);
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}
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/*
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* If we have an entry in the index cache, then we want to
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* make sure that it matches head.
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*/
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- if (index && !same(index, head))
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- return reject_merge(index, o);
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+ if (index && !same(index, head)) {
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+ if (S_ISSPARSEDIR(index->ce_mode))
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+ return merged_sparse_dir(stages, 4, o);
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+ else
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+ return reject_merge(index, o);
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+ }
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if (head) {
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/* #5ALT, #15 */
@@ -2714,11 +2722,21 @@ int threeway_merge(const struct cache_entry * const *stages,
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}
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- /* Below are "no merge" cases, which require that the index be
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- * up-to-date to avoid the files getting overwritten with
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- * conflict resolution files.
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- */
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+ /* Handle "no merge" cases (see t/t1000-read-tree-m-3way.sh) */
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if (index) {
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+ /*
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+ * If we've reached the "no merge" cases and we're merging
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+ * a sparse directory, we may have an "edit/edit" conflict that
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+ * can be resolved by individually merging directory contents.
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+ */
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+ if (S_ISSPARSEDIR(index->ce_mode))
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+ return merged_sparse_dir(stages, 4, o);
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+
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+ /*
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+ * If we're not merging a sparse directory, ensure the index is
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+ * up-to-date to avoid files getting overwritten with conflict
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+ * resolution files
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+ */
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if (verify_uptodate(index, o))
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return -1;
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}