environment: move access to "core.sparseCheckout" into repo settings

The `core.sparseCheckout` config value is stored in the global
variable `core_apply_sparse_checkout`. This may cause issues in
the case where one is handling multiple different repositories in a
Git single process with different values for that config key.
The global state also blocks the goal of libifying Git.

Refactor the code to store it in `sparse_checkout` in
`struct repo-settings` and update the callers

Note that in `builtin/sparse-checkout.c`, `struct repository` parameter
in `sparse_checkout_list()` is used to avoid the use of `the_repository`
and `update_cone_mode()` is also adapted to accept `struct repository`.

Based-on-patch-by: Ayush Chandekar <ayu.chandekar@gmail.com>
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Usman Akinyemi <usmanakinyemi202@gmail.com>
Signed-off-by: Olamide Caleb Bello <belkid98@gmail.com>

Author: cloobTech

builtin/backfill.c

@@ -139,7 +139,7 @@ int cmd_backfill(int argc, const char **argv, const char *prefix, struct reposit
 	repo_config(repo, git_default_config, NULL);
 
 	if (ctx.sparse < 0)
-		ctx.sparse = core_apply_sparse_checkout;
+		ctx.sparse = repo->settings.sparse_checkout;
 
 	result = do_backfill(&ctx);
 	backfill_context_clear(&ctx);

builtin/clone.c

@@ -623,7 +623,7 @@ static int git_sparse_checkout_init(const char *repo)
 	 * We must apply the setting in the current process
 	 * for the later checkout to use the sparse-checkout file.
 	 */
-	core_apply_sparse_checkout = 1;
+	the_repository->settings.sparse_checkout = 1;
 
 	cmd.git_cmd = 1;
 	if (run_command(&cmd)) {

builtin/mv.c

@@ -572,7 +572,7 @@ int cmd_mv(int argc,
 		rename_index_entry_at(the_repository->index, pos, dst);
 
 		if (ignore_sparse &&
-		    core_apply_sparse_checkout &&
+		    the_repository->settings.sparse_checkout &&
 		    core_sparse_checkout_cone) {
 			/*
 			 * NEEDSWORK: we are *not* paying attention to

builtin/sparse-checkout.c

@@ -53,7 +53,7 @@ static char const * const builtin_sparse_checkout_list_usage[] = {
 };
 
 static int sparse_checkout_list(int argc, const char **argv, const char *prefix,
-				struct repository *repo UNUSED)
+				struct repository *repo)
 {
 	static struct option builtin_sparse_checkout_list_options[] = {
 		OPT_END(),
@@ -63,7 +63,7 @@ static int sparse_checkout_list(int argc, const char **argv, const char *prefix,
 	int res;
 
 	setup_work_tree();
-	if (!core_apply_sparse_checkout)
+	if (!repo->settings.sparse_checkout)
 		die(_("this worktree is not sparse"));
 
 	argc = parse_options(argc, argv, prefix,
@@ -398,13 +398,13 @@ static int set_config(struct repository *repo,
 	return 0;
 }
 
-static enum sparse_checkout_mode update_cone_mode(int *cone_mode) {
+static enum sparse_checkout_mode update_cone_mode(struct repository *repo, int *cone_mode) {
 	/* If not specified, use previous definition of cone mode */
-	if (*cone_mode == -1 && core_apply_sparse_checkout)
+	if (*cone_mode == -1 && repo->settings.sparse_checkout)
 		*cone_mode = core_sparse_checkout_cone;
 
 	/* Set cone/non-cone mode appropriately */
-	core_apply_sparse_checkout = 1;
+	repo->settings.sparse_checkout = 1;
 	if (*cone_mode == 1 || *cone_mode == -1) {
 		core_sparse_checkout_cone = 1;
 		return MODE_CONE_PATTERNS;
@@ -418,9 +418,9 @@ static int update_modes(struct repository *repo, int *cone_mode, int *sparse_ind
 	int mode, record_mode;
 
 	/* Determine if we need to record the mode; ensure sparse checkout on */
-	record_mode = (*cone_mode != -1) || !core_apply_sparse_checkout;
+	record_mode = (*cone_mode != -1) || !repo->settings.sparse_checkout;
 
-	mode = update_cone_mode(cone_mode);
+	mode = update_cone_mode(repo, cone_mode);
 	if (record_mode && set_config(repo, mode))
 		return 1;
 
@@ -699,9 +699,9 @@ static int modify_pattern_list(struct repository *repo,
 		break;
 	}
 
-	if (!core_apply_sparse_checkout) {
+	if (!repo->settings.sparse_checkout) {
 		set_config(repo, MODE_ALL_PATTERNS);
-		core_apply_sparse_checkout = 1;
+		repo->settings.sparse_checkout = 1;
 		changed_config = 1;
 	}
 
@@ -798,7 +798,7 @@ static int sparse_checkout_add(int argc, const char **argv, const char *prefix,
 	int ret;
 
 	setup_work_tree();
-	if (!core_apply_sparse_checkout)
+	if (!repo->settings.sparse_checkout)
 		die(_("no sparse-checkout to add to"));
 
 	repo_read_index(repo);
@@ -907,7 +907,7 @@ static int sparse_checkout_reapply(int argc, const char **argv,
 	};
 
 	setup_work_tree();
-	if (!core_apply_sparse_checkout)
+	if (!repo->settings.sparse_checkout)
 		die(_("must be in a sparse-checkout to reapply sparsity patterns"));
 
 	reapply_opts.cone_mode = -1;
@@ -969,7 +969,7 @@ static int sparse_checkout_clean(int argc, const char **argv,
 	};
 
 	setup_work_tree();
-	if (!core_apply_sparse_checkout)
+	if (!repo->settings.sparse_checkout)
 		die(_("must be in a sparse-checkout to clean directories"));
 	if (!core_sparse_checkout_cone)
 		die(_("must be in a cone-mode sparse-checkout to clean directories"));
@@ -1061,7 +1061,7 @@ static int sparse_checkout_disable(int argc, const char **argv,
 	hashmap_init(&pl.recursive_hashmap, pl_hashmap_cmp, NULL, 0);
 	hashmap_init(&pl.parent_hashmap, pl_hashmap_cmp, NULL, 0);
 	pl.use_cone_patterns = 0;
-	core_apply_sparse_checkout = 1;
+	repo->settings.sparse_checkout = 1;
 
 	add_pattern("/*", empty_base, 0, &pl, 0);
 
@@ -1144,7 +1144,7 @@ static int sparse_checkout_check_rules(int argc, const char **argv, const char *
 	if (check_rules_opts.rules_file && check_rules_opts.cone_mode < 0)
 		check_rules_opts.cone_mode = 1;
 
-	update_cone_mode(&check_rules_opts.cone_mode);
+	update_cone_mode(repo, &check_rules_opts.cone_mode);
 	pl.use_cone_patterns = core_sparse_checkout_cone;
 	if (check_rules_opts.rules_file) {
 		fp = xfopen(check_rules_opts.rules_file, "r");

builtin/worktree.c

@@ -536,7 +536,7 @@ static int add_worktree(const char *path, const char *refname,
 	 * If the current worktree has sparse-checkout enabled, then copy
 	 * the sparse-checkout patterns from the current worktree.
 	 */
-	if (core_apply_sparse_checkout)
+	if (the_repository->settings.sparse_checkout)
 		copy_sparse_checkout(sb_repo.buf);
 
 	/*

dir.c

@@ -1551,7 +1551,7 @@ enum pattern_match_result path_matches_pattern_list(
 
 int init_sparse_checkout_patterns(struct index_state *istate)
 {
-	if (!core_apply_sparse_checkout)
+	if (!istate->repo->settings.sparse_checkout)
 		return 1;
 	if (istate->sparse_checkout_patterns)
 		return 0;

environment.c

@@ -75,7 +75,6 @@ enum push_default_type push_default = PUSH_DEFAULT_UNSPECIFIED;
 #endif
 enum object_creation_mode object_creation_mode = OBJECT_CREATION_MODE;
 int grafts_keep_true_parents;
-int core_apply_sparse_checkout;
 int core_sparse_checkout_cone;
 int sparse_expect_files_outside_of_patterns;
 int precomposed_unicode = -1; /* see probe_utf8_pathname_composition() */
@@ -544,11 +543,6 @@ static int git_default_core_config(const char *var, const char *value,
 		return 0;
 	}
 
-	if (!strcmp(var, "core.sparsecheckout")) {
-		core_apply_sparse_checkout = git_config_bool(var, value);
-		return 0;
-	}
-
 	if (!strcmp(var, "core.sparsecheckoutcone")) {
 		core_sparse_checkout_cone = git_config_bool(var, value);
 		return 0;

environment.h

@@ -162,7 +162,6 @@ extern int precomposed_unicode;
 extern int protect_hfs;
 extern int protect_ntfs;
 
-extern int core_apply_sparse_checkout;
 extern int core_sparse_checkout_cone;
 extern int sparse_expect_files_outside_of_patterns;
 

repo-settings.c

@@ -84,6 +84,7 @@ void prepare_repo_settings(struct repository *r)
 		      &r->settings.pack_use_bitmap_boundary_traversal,
 		      r->settings.pack_use_bitmap_boundary_traversal);
 	repo_cfg_bool(r, "core.usereplacerefs", &r->settings.read_replace_refs, 1);
+	repo_cfg_bool(r, "core.sparsecheckout", &r->settings.sparse_checkout, 0);
 
 	/*
 	 * The GIT_TEST_MULTI_PACK_INDEX variable is special in that

repo-settings.h

@@ -39,6 +39,7 @@ struct repo_settings {
 
 	int shared_repository;
 	int shared_repository_initialized;
+	int sparse_checkout;
 
 	/*
 	 * Does this repository have core.useReplaceRefs=true (on by