Re: [PATCH v7 15/16] wt-status: expand added sparse directory entries

>
> From: Derrick Stolee <dstolee@microsoft.com>
>
> It is difficult, but possible, to get into a state where we intend to
> add a directory that is outside of the sparse-checkout definition. Add a
> test to t1092-sparse-checkout-compatibility.sh that demonstrates this
> using a combination of 'git reset --mixed' and 'git checkout --orphan'.
>
> This test failed before because the output of 'git status
> --porcelain=v2' would not match on the lines for folder1/:
>
> * The sparse-checkout repo (with a full index) would output each path
>   name that is intended to be added.
>
> * The sparse-index repo would only output that "folder1/" is staged for
>   addition.
>
> The status should report the full list of files to be added, and so this
> sparse-directory entry should be expanded to a full list when reaching
> it inside the wt_status_collect_changes_initial() method. Use
> read_tree_at() to assist.
>
> Somehow, this loop over the cache entries was not guarded by
> ensure_full_index() as intended.
>
> Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
> ---
>  t/t1092-sparse-checkout-compatibility.sh | 33 +++++++++++++++
>  wt-status.c                              | 51 ++++++++++++++++++++++++
>  2 files changed, 84 insertions(+)
>
> diff --git a/t/t1092-sparse-checkout-compatibility.sh b/t/t1092-sparse-checkout-compatibility.sh
> index fed0440bafe..df217a2d10b 100755
> --- a/t/t1092-sparse-checkout-compatibility.sh
> +++ b/t/t1092-sparse-checkout-compatibility.sh
> @@ -545,4 +545,37 @@ test_expect_success 'sparse-index is not expanded' '
>         test_region ! index ensure_full_index trace2.txt
>  '
>
> +test_expect_success 'reset mixed and checkout orphan' '
> +       init_repos &&
> +
> +       test_all_match git checkout rename-out-to-in &&
> +
> +       # Sparse checkouts do not agree with full checkouts about
> +       # how to report a directory/file conflict during a reset.
> +       # This command would fail with test_all_match because the
> +       # full checkout reports "T folder1/0/1" while a sparse
> +       # checkout reports "D folder1/0/1". This matches because
> +       # the sparse checkouts skip "adding" the other side of
> +       # the conflict.

> +       test_sparse_match git reset --mixed HEAD~1 &&
> +       test_sparse_match test-tool read-cache --table --expand &&
> +       test_sparse_match git status --porcelain=v2 &&
> +
> +       # At this point, sparse-checkouts behave differently
> +       # from the full-checkout.
> +       test_sparse_match git checkout --orphan new-branch &&
> +       test_sparse_match test-tool read-cache --table --expand &&
> +       test_sparse_match git status --porcelain=v2
> +'
> +
> +test_expect_success 'add everything with deep new file' '
> +       init_repos &&
> +
> +       run_on_sparse git sparse-checkout set deep/deeper1/deepest &&
> +
> +       run_on_all touch deep/deeper1/x &&
> +       test_all_match git add . &&
> +       test_all_match git status --porcelain=v2
> +'
> +
>  test_done
> diff --git a/wt-status.c b/wt-status.c
> index 96db3e74962..0317baef87e 100644
> --- a/wt-status.c
> +++ b/wt-status.c
> @@ -657,6 +657,36 @@ static void wt_status_collect_changes_index(struct wt_status *s)
>         clear_pathspec(&rev.prune_data);
>  }
>
> +static int add_file_to_list(const struct object_id *oid,
> +                           struct strbuf *base, const char *path,
> +                           unsigned int mode, void *context)
> +{
> +       struct string_list_item *it;
> +       struct wt_status_change_data *d;
> +       struct wt_status *s = context;
> +       struct strbuf full_name = STRBUF_INIT;
> +
> +       if (S_ISDIR(mode))
> +               return READ_TREE_RECURSIVE;
> +
> +       strbuf_add(&full_name, base->buf, base->len);
> +       strbuf_addstr(&full_name, path);
> +       it = string_list_insert(&s->change, full_name.buf);
> +       d = it->util;
> +       if (!d) {
> +               CALLOC_ARRAY(d, 1);
> +               it->util = d;
> +       }
> +
> +       d->index_status = DIFF_STATUS_ADDED;
> +       /* Leave {mode,oid}_head zero for adds. */
> +       d->mode_index = mode;
> +       oidcpy(&d->oid_index, oid);
> +       s->committable = 1;
> +       strbuf_release(&full_name);
> +       return 0;
> +}
> +
>  static void wt_status_collect_changes_initial(struct wt_status *s)
>  {
>         struct index_state *istate = s->repo->index;
> @@ -671,6 +701,27 @@ static void wt_status_collect_changes_initial(struct wt_status *s)
>                         continue;
>                 if (ce_intent_to_add(ce))
>                         continue;
> +               if (S_ISSPARSEDIR(ce->ce_mode)) {
> +                       /*
> +                        * This is a sparse directory entry, so we want to collect all
> +                        * of the added files within the tree. This requires recursively
> +                        * expanding the trees to find the elements that are new in this
> +                        * tree and marking them with DIFF_STATUS_ADDED.
> +                        */
> +                       struct strbuf base = STRBUF_INIT;
> +                       struct pathspec ps = { 0 };
> +                       struct tree *tree = lookup_tree(istate->repo, &ce->oid);
> +
> +                       ps.recursive = 1;
> +                       ps.has_wildcard = 1;
> +                       ps.max_depth = -1;
> +
> +                       strbuf_add(&base, ce->name, ce->ce_namelen);
> +                       read_tree_at(istate->repo, tree, &base, &ps,
> +                                    add_file_to_list, s);
> +                       continue;
> +               }
> +
>                 it = string_list_insert(&s->change, ce->name);
>                 d = it->util;
>                 if (!d) {
> --
> gitgitgadget