Merge branch 'ds/sparse-colon-path' into next

"git show :<path>" learned to work better with the sparse-index
feature.

* ds/sparse-colon-path:
  rev-parse: integrate with sparse index
  object-name: diagnose trees in index properly
  object-name: reject trees found in the index
  show: integrate with the sparse index
  t1092: add compatibility tests for 'git show'

builtin/log.c

@@ -669,6 +669,11 @@ int cmd_show(int argc, const char **argv, const char *prefix)
 	init_log_defaults();
 	git_config(git_log_config, NULL);
 
+	if (the_repository->gitdir) {
+		prepare_repo_settings(the_repository);
+		the_repository->settings.command_requires_full_index = 0;
+	}
+
 	memset(&match_all, 0, sizeof(match_all));
 	repo_init_revisions(the_repository, &rev, prefix);
 	git_config(grep_config, &rev.grep_filter);

builtin/rev-parse.c

@@ -723,6 +723,9 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
 			prefix = setup_git_directory();
 			git_config(git_default_config, NULL);
 			did_repo_setup = 1;
+
+			prepare_repo_settings(the_repository);
+			the_repository->settings.command_requires_full_index = 0;
 		}
 
 		if (!strcmp(arg, "--")) {

object-name.c

@@ -1832,7 +1832,8 @@ static void diagnose_invalid_index_path(struct repository *r,
 		pos = -pos - 1;
 	if (pos < istate->cache_nr) {
 		ce = istate->cache[pos];
-		if (ce_namelen(ce) == namelen &&
+		if (!S_ISSPARSEDIR(ce->ce_mode) &&
+		    ce_namelen(ce) == namelen &&
 		    !memcmp(ce->name, filename, namelen))
 			die(_("path '%s' is in the index, but not at stage %d\n"
 			    "hint: Did you mean ':%d:%s'?"),
@@ -1848,7 +1849,8 @@ static void diagnose_invalid_index_path(struct repository *r,
 		pos = -pos - 1;
 	if (pos < istate->cache_nr) {
 		ce = istate->cache[pos];
-		if (ce_namelen(ce) == fullname.len &&
+		if (!S_ISSPARSEDIR(ce->ce_mode) &&
+		    ce_namelen(ce) == fullname.len &&
 		    !memcmp(ce->name, fullname.buf, fullname.len))
 			die(_("path '%s' is in the index, but not '%s'\n"
 			    "hint: Did you mean ':%d:%s' aka ':%d:./%s'?"),
@@ -1881,6 +1883,20 @@ static char *resolve_relative_path(struct repository *r, const char *rel)
 			   rel);
 }
 
+static int reject_tree_in_index(struct repository *repo,
+				int only_to_die,
+				const struct cache_entry *ce,
+				int stage,
+				const char *prefix,
+				const char *cp)
+{
+	if (!S_ISSPARSEDIR(ce->ce_mode))
+		return 0;
+	if (only_to_die)
+		diagnose_invalid_index_path(repo, stage, prefix, cp);
+	return -1;
+}
+
 static enum get_oid_result get_oid_with_context_1(struct repository *repo,
 				  const char *name,
 				  unsigned flags,
@@ -1955,9 +1971,12 @@ static enum get_oid_result get_oid_with_context_1(struct repository *repo,
 			    memcmp(ce->name, cp, namelen))
 				break;
 			if (ce_stage(ce) == stage) {
+				free(new_path);
+				if (reject_tree_in_index(repo, only_to_die, ce,
+							 stage, prefix, cp))
+					return -1;
 				oidcpy(oid, &ce->oid);
 				oc->mode = ce->ce_mode;
-				free(new_path);
 				return 0;
 			}
 			pos++;

t/t1092-sparse-checkout-compatibility.sh

@@ -1200,6 +1200,33 @@ test_expect_success 'clean' '
 	test_sparse_match test_path_is_dir folder1
 '
 
+for builtin in show rev-parse
+do
+	test_expect_success "$builtin (cached blobs/trees)" "
+		init_repos &&
+
+		test_all_match git $builtin :a &&
+		test_all_match git $builtin :deep/a &&
+		test_sparse_match git $builtin :folder1/a &&
+
+		# The error message differs depending on whether
+		# the directory exists in the worktree.
+		test_all_match test_must_fail git $builtin :deep/ &&
+		test_must_fail git -C full-checkout $builtin :folder1/ &&
+		test_sparse_match test_must_fail git $builtin :folder1/ &&
+
+		# Change the sparse cone for an extra case:
+		run_on_sparse git sparse-checkout set deep/deeper1 &&
+
+		# deep/deeper2 is a sparse directory in the sparse index.
+		test_sparse_match test_must_fail git $builtin :deep/deeper2/ &&
+
+		# deep/deeper2/deepest is not in the sparse index, but
+		# will trigger an index expansion.
+		test_sparse_match test_must_fail git $builtin :deep/deeper2/deepest/
+	"
+done
+
 test_expect_success 'submodule handling' '
 	init_repos &&
 
@@ -1448,6 +1475,15 @@ test_expect_success 'sparse index is not expanded: diff' '
 	ensure_not_expanded diff --cached
 '
 
+test_expect_success 'sparse index is not expanded: show and rev-parse' '
+	init_repos &&
+
+	ensure_not_expanded show :a &&
+	ensure_not_expanded show :deep/a &&
+	ensure_not_expanded rev-parse :a &&
+	ensure_not_expanded rev-parse :deep/a
+'
+
 test_expect_success 'sparse index is not expanded: update-index' '
 	init_repos &&