environment: move access to "core.sparsecheckout" into repo_settings

The setting "core.sparsecheckout" is stored in the global
`core_apply_sparse_checkout` and is populated in config.c. Refactor the
code to store it in the variable `sparse_checkout` in the struct
`repo_settings`.

Call `prepare_repo_settings()` where necessary to ensure the `struct
repo_settings` is initialized before use:
- In "builtin/backfill.c", "builtin/mv.c" and "builtin/clone.c" call
  `prepare_repo_settings()` since their respective `cmd_*()` functions
  did not call it earlier.
- In "dir.c", the function using 'settings.sparse_checkout' is invoked
  in multiple files that do not call `prepare_repo_settings()`, hence
  add a call directly to that function.
- In "sparse-checkout.c", add a call to `prepare_repo_settings()` inside
  `is_sparse_index_allowed()`, as it is used widely and relies on the
  setting.
- In "wt-status.c", call `prepare_repo_settings()` before accessing
  the setting because the function using it is commonly used.

Avoid reduntant calls to `prepare_repo_settings()` where it is already
present:
- In "builtin/worktree.c", it is already invoked in `cmd_worktree()`
  before the setting is accessed.
- In "unpack-tress.c", the function accessing the setting already calls
  it.

This also allows us to remove the definition `#define
USE_THE_REPOSITORY_VARIABLE` from the file 'builtin/backfill.c'.

This change is part of an ongoing effort to eliminate global variables,
improve modularity and help libify the codebase.

Mentored-by: Christian Couder <[email protected]>
Mentored-by: Ghanshyam Thakkar <[email protected]>
Signed-off-by: Ayush Chandekar <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: ayu-ch

builtin/backfill.c

@@ -1,6 +1,3 @@
-/* We need this macro to access core_apply_sparse_checkout */
-#define USE_THE_REPOSITORY_VARIABLE
-
 #include "builtin.h"
 #include "git-compat-util.h"
 #include "config.h"
@@ -137,9 +134,9 @@ int cmd_backfill(int argc, const char **argv, const char *prefix, struct reposit
 			     0);
 
 	repo_config(repo, git_default_config, NULL);
-
+	prepare_repo_settings(repo);
 	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

@@ -617,11 +617,12 @@ static int git_sparse_checkout_init(const char *repo)
 	int result = 0;
 	strvec_pushl(&cmd.args, "-C", repo, "sparse-checkout", "set", NULL);
 
+	prepare_repo_settings(the_repository);
 	/*
 	 * 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/grep.c

@@ -481,7 +481,7 @@ static int grep_submodule(struct grep_opt *opt,
 	 *	"forget" the sparse-index feature switch. As a result, the index
 	 *	of these submodules are expanded unexpectedly.
 	 *
-	 * 2. "core_apply_sparse_checkout"
+	 * 2. "settings.sparse_checkout"
 	 *	When running `grep` in the superproject, this setting is
 	 *	populated using the superproject's configs. However, once
 	 *	initialized, this config is globally accessible and is read by

builtin/mv.c

@@ -570,9 +570,9 @@ int cmd_mv(int argc,
 						       &st,
 						       0);
 		rename_index_entry_at(the_repository->index, pos, dst);
-
+		prepare_repo_settings(the_repository);
 		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

@@ -62,7 +62,7 @@ static int sparse_checkout_list(int argc, const char **argv, const char *prefix,
 	int res;
 
 	setup_work_tree();
-	if (!core_apply_sparse_checkout)
+	if (!the_repository->settings.sparse_checkout)
 		die(_("this worktree is not sparse"));
 
 	argc = parse_options(argc, argv, prefix,
@@ -397,11 +397,11 @@ static int set_config(enum sparse_checkout_mode mode)
 
 static enum sparse_checkout_mode update_cone_mode(int *cone_mode) {
 	/* If not specified, use previous definition of cone mode */
-	if (*cone_mode == -1 && core_apply_sparse_checkout)
+	if (*cone_mode == -1 && the_repository->settings.sparse_checkout)
 		*cone_mode = core_sparse_checkout_cone;
 
 	/* Set cone/non-cone mode appropriately */
-	core_apply_sparse_checkout = 1;
+	the_repository->settings.sparse_checkout = 1;
 	if (*cone_mode == 1 || *cone_mode == -1) {
 		core_sparse_checkout_cone = 1;
 		return MODE_CONE_PATTERNS;
@@ -415,7 +415,7 @@ static int update_modes(int *cone_mode, int *sparse_index)
 	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) || !the_repository->settings.sparse_checkout;
 
 	mode = update_cone_mode(cone_mode);
 	if (record_mode && set_config(mode))
@@ -695,9 +695,9 @@ static int modify_pattern_list(struct strvec *args, int use_stdin,
 		break;
 	}
 
-	if (!core_apply_sparse_checkout) {
+	if (!the_repository->settings.sparse_checkout) {
 		set_config(MODE_ALL_PATTERNS);
-		core_apply_sparse_checkout = 1;
+		the_repository->settings.sparse_checkout = 1;
 		changed_config = 1;
 	}
 
@@ -793,7 +793,7 @@ static int sparse_checkout_add(int argc, const char **argv, const char *prefix,
 	int ret;
 
 	setup_work_tree();
-	if (!core_apply_sparse_checkout)
+	if (!the_repository->settings.sparse_checkout)
 		die(_("no sparse-checkout to add to"));
 
 	repo_read_index(the_repository);
@@ -902,7 +902,7 @@ static int sparse_checkout_reapply(int argc, const char **argv,
 	};
 
 	setup_work_tree();
-	if (!core_apply_sparse_checkout)
+	if (!the_repository->settings.sparse_checkout)
 		die(_("must be in a sparse-checkout to reapply sparsity patterns"));
 
 	reapply_opts.cone_mode = -1;
@@ -935,7 +935,7 @@ static int sparse_checkout_disable(int argc, const char **argv,
 	struct pattern_list pl;
 
 	/*
-	 * We do not exit early if !core_apply_sparse_checkout; due to the
+	 * We do not exit early if !sparse_checkout; due to the
 	 * ability for users to manually muck things up between
 	 *   direct editing of .git/info/sparse-checkout
 	 *   running read-tree -m u HEAD or update-index --skip-worktree
@@ -961,11 +961,10 @@ 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;
+	the_repository->settings.sparse_checkout = 1;
 
 	add_pattern("/*", empty_base, 0, &pl, 0);
 
-	prepare_repo_settings(the_repository);
 	the_repository->settings.sparse_index = 0;
 
 	if (update_working_directory(&pl))

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);
 
 	/*

config.c

@@ -1612,11 +1612,6 @@ 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;

dir.c

@@ -1503,7 +1503,8 @@ enum pattern_match_result path_matches_pattern_list(
 
 int init_sparse_checkout_patterns(struct index_state *istate)
 {
-	if (!core_apply_sparse_checkout)
+	prepare_repo_settings(istate->repo);
+	if (!istate->repo->settings.sparse_checkout)
 		return 1;
 	if (istate->sparse_checkout_patterns)
 		return 0;

environment.c

@@ -64,7 +64,6 @@ 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 merge_log_config = -1;

environment.h

@@ -160,7 +160,6 @@ 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;