update-index: integrate with sparse index

Enable use of the sparse index with `update-index`. Most variations of
`update-index` work without explicitly expanding the index or making any
other updates in or outside of `update-index.c`.

The one usage requiring additional changes is `--cacheinfo`; if a file
inside a sparse directory was specified, the index would not be expanded
until after the cache tree is invalidated, leading to a mismatch between the
index and cache tree. This scenario is handled by rearranging
`add_index_entry_with_check`, allowing `index_name_stage_pos` to expand the
index *before* attempting to invalidate the relevant cache tree path,
avoiding cache tree/index corruption.

Signed-off-by: Victoria Dye <vdye@github.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/update-index.c b/builtin/update-index.c
index 187203e8bb53cbeaf80d2f4b89c04134a2a5c95f..605cc693bbd106c5e784f21e958199f7e0cc713d 100644 (file)
--- a/builtin/update-index.c
+++ b/builtin/update-index.c
@@ -1077,6 +1077,9 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 
        git_config(git_default_config, NULL);
 
+       prepare_repo_settings(r);
+       the_repository->settings.command_requires_full_index = 0;
+
        /* we will diagnose later if it turns out that we need to update it */
        newfd = hold_locked_index(&lock_file, 0);
        if (newfd < 0)

diff --git a/read-cache.c b/read-cache.c
index cbe73f14e5e7efc63b20e80a2702fb5c0dea9a5d..b4600e954b6c817e198a7ebf7f53c9a10ca61faa 100644 (file)
--- a/read-cache.c
+++ b/read-cache.c
@@ -1339,9 +1339,6 @@ static int add_index_entry_with_check(struct index_state *istate, struct cache_e
        int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
        int new_only = option & ADD_CACHE_NEW_ONLY;
 
-       if (!(option & ADD_CACHE_KEEP_CACHE_TREE))
-               cache_tree_invalidate_path(istate, ce->name);
-
        /*
         * If this entry's path sorts after the last entry in the index,
         * we can avoid searching for it.
@@ -1352,6 +1349,13 @@ static int add_index_entry_with_check(struct index_state *istate, struct cache_e
        else
                pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce), EXPAND_SPARSE);
 
+       /*
+        * Cache tree path should be invalidated only after index_name_stage_pos,
+        * in case it expands a sparse index.
+        */
+       if (!(option & ADD_CACHE_KEEP_CACHE_TREE))
+               cache_tree_invalidate_path(istate, ce->name);
+
        /* existing match? Just replace it. */
        if (pos >= 0) {
                if (!new_only)

diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
index 91f849f541e22f1d777b4d395b224b5dbcd7f8c7..fceaba7101d9ad11f57bbe327371d37d3d190acb 100755 (executable)
--- a/t/t1092-sparse-checkout-compatibility.sh
+++ b/t/t1092-sparse-checkout-compatibility.sh
@@ -1253,6 +1253,21 @@ test_expect_success 'sparse index is not expanded: diff' '
        ensure_not_expanded diff --cached
 '
 
+test_expect_success 'sparse index is not expanded: update-index' '
+       init_repos &&
+
+       deep_a_oid=$(git -C full-checkout rev-parse update-deep:deep/a) &&
+       ensure_not_expanded update-index --cacheinfo 100644 $deep_a_oid deep/a &&
+
+       echo "test" >sparse-index/README.md &&
+       echo "test2" >sparse-index/a &&
+       rm -f sparse-index/deep/a &&
+
+       ensure_not_expanded update-index --add README.md &&
+       ensure_not_expanded update-index a &&
+       ensure_not_expanded update-index --remove deep/a
+'
+
 test_expect_success 'sparse index is not expanded: blame' '
        init_repos &&