submodule: sparse-index should not collapse links

A submodule is stored as a "Git link" that actually points to a commit
within a submodule. Submodules are populated or not depending on
submodule configuration, not sparse-checkout. To ensure that the
sparse-index feature integrates correctly with submodules, we should not
collapse a directory if there is a Git link within its range.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/sparse-index.c b/sparse-index.c
index 619ff7c..7631f7b 100644 (file)
--- a/sparse-index.c
+++ b/sparse-index.c
@@ -52,6 +52,7 @@ static int convert_to_sparse_rec(struct index_state *istate,
                struct cache_entry *ce = istate->cache[i];
 
                if (ce_stage(ce) ||
+                   S_ISGITLINK(ce->ce_mode) ||
                    !(ce->ce_flags & CE_SKIP_WORKTREE))
                        can_convert = 0;
        }

diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index 1e888d1..cba5f89 100755 (executable)
--- a/t/t1092-sparse-checkout-compatibility.sh
+++ b/t/t1092-sparse-checkout-compatibility.sh
@@ -376,4 +376,21 @@ test_expect_success 'clean' '
        test_sparse_match test_path_is_dir folder1
 '
 
+test_expect_success 'submodule handling' '
+       init_repos &&
+
+       test_all_match mkdir modules &&
+       test_all_match touch modules/a &&
+       test_all_match git add modules &&
+       test_all_match git commit -m "add modules directory" &&
+
+       run_on_all git submodule add "$(pwd)/initial-repo" modules/sub &&
+       test_all_match git commit -m "add submodule" &&
+
+       # having a submodule prevents "modules" from collapse
+       test-tool -C sparse-index read-cache --table >cache &&
+       grep "100644 blob .*    modules/a" cache &&
+       grep "160000 commit $(git -C initial-repo rev-parse HEAD)       modules/sub" cache
+'
+
 test_done