repo-settings: parse core.untrackedCache

The core.untrackedCache config setting is slightly complicated,
so clarify its use and centralize its parsing into the repo
settings.

The default value is "keep" (returned as -1), which persists the
untracked cache if it exists.

If the value is set as "false" (returned as 0), then remove the
untracked cache if it exists.

If the value is set as "true" (returned as 1), then write the
untracked cache and persist it.

Instead of relying on magic values of -1, 0, and 1, split these
options into an enum. This allows the use of "-1" as a
default value. After parsing the config options, if the value is
unset we can initialize it to UNTRACKED_CACHE_KEEP.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/update-index.c

@@ -966,6 +966,7 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 	struct parse_opt_ctx_t ctx;
 	strbuf_getline_fn getline_fn;
 	int parseopt_state = PARSE_OPT_UNKNOWN;
+	struct repository *r = the_repository;
 	struct option options[] = {
 		OPT_BIT('q', NULL, &refresh_args.flags,
 			N_("continue refresh even when index needs update"),
@@ -1180,11 +1181,12 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 		remove_split_index(&the_index);
 	}
 
+	prepare_repo_settings(r);
 	switch (untracked_cache) {
 	case UC_UNSPECIFIED:
 		break;
 	case UC_DISABLE:
-		if (git_config_get_untracked_cache() == 1)
+		if (r->settings.core_untracked_cache == UNTRACKED_CACHE_WRITE)
 			warning(_("core.untrackedCache is set to true; "
 				  "remove or change it, if you really want to "
 				  "disable the untracked cache"));
@@ -1196,7 +1198,7 @@ int cmd_update_index(int argc, const char **argv, const char *prefix)
 		return !test_if_untracked_cache_is_supported();
 	case UC_ENABLE:
 	case UC_FORCE:
-		if (git_config_get_untracked_cache() == 0)
+		if (r->settings.core_untracked_cache == UNTRACKED_CACHE_REMOVE)
 			warning(_("core.untrackedCache is set to false; "
 				  "remove or change it, if you really want to "
 				  "enable the untracked cache"));

config.c

@@ -2277,30 +2277,6 @@ int git_config_get_expiry_in_days(const char *key, timestamp_t *expiry, timestam
 	return -1; /* thing exists but cannot be parsed */
 }
 
-int git_config_get_untracked_cache(void)
-{
-	int val = -1;
-	const char *v;
-
-	/* Hack for test programs like test-dump-untracked-cache */
-	if (ignore_untracked_cache_config)
-		return -1;
-
-	if (!git_config_get_maybe_bool("core.untrackedcache", &val))
-		return val;
-
-	if (!git_config_get_value("core.untrackedcache", &v)) {
-		if (!strcasecmp(v, "keep"))
-			return -1;
-
-		error(_("unknown core.untrackedCache value '%s'; "
-			"using 'keep' default value"), v);
-		return -1;
-	}
-
-	return -1; /* default value */
-}
-
 int git_config_get_split_index(void)
 {
 	int val;

read-cache.c

@@ -1845,18 +1845,17 @@ static void check_ce_order(struct index_state *istate)
 
 static void tweak_untracked_cache(struct index_state *istate)
 {
-	switch (git_config_get_untracked_cache()) {
-	case -1: /* keep: do nothing */
-		break;
-	case 0: /* false */
+	struct repository *r = the_repository;
+
+	prepare_repo_settings(r);
+
+	if (r->settings.core_untracked_cache  == UNTRACKED_CACHE_REMOVE) {
 		remove_untracked_cache(istate);
-		break;
-	case 1: /* true */
-		add_untracked_cache(istate);
-		break;
-	default: /* unknown value: do nothing */
-		break;
+		return;
 	}
+
+	if (r->settings.core_untracked_cache == UNTRACKED_CACHE_WRITE)
+		add_untracked_cache(istate);
 }
 
 static void tweak_split_index(struct index_state *istate)

repo-settings.c

@@ -7,6 +7,7 @@
 void prepare_repo_settings(struct repository *r)
 {
 	int value;
+	char *strval;
 
 	if (r->settings.initialized)
 		return;
@@ -23,7 +24,25 @@ void prepare_repo_settings(struct repository *r)
 
 	if (!repo_config_get_bool(r, "index.version", &value))
 		r->settings.index_version = value;
+	if (!repo_config_get_maybe_bool(r, "core.untrackedcache", &value)) {
+		if (value == 0)
+			r->settings.core_untracked_cache = UNTRACKED_CACHE_REMOVE;
+		else
+			r->settings.core_untracked_cache = UNTRACKED_CACHE_WRITE;
+	} else if (!repo_config_get_string(r, "core.untrackedcache", &strval)) {
+		if (!strcasecmp(strval, "keep"))
+			r->settings.core_untracked_cache = UNTRACKED_CACHE_KEEP;
+
+		free(strval);
+	}
+
 
 	if (!repo_config_get_bool(r, "pack.usesparse", &value))
 		r->settings.pack_use_sparse = value;
+
+	/* Hack for test programs like test-dump-untracked-cache */
+	if (ignore_untracked_cache_config)
+		r->settings.core_untracked_cache = UNTRACKED_CACHE_KEEP;
+	else
+		UPDATE_DEFAULT_BOOL(r->settings.core_untracked_cache, UNTRACKED_CACHE_KEEP);
 }

repository.h

@@ -11,6 +11,13 @@ struct pathspec;
 struct raw_object_store;
 struct submodule_cache;
 
+enum untracked_cache_setting {
+	UNTRACKED_CACHE_UNSET = -1,
+	UNTRACKED_CACHE_REMOVE = 0,
+	UNTRACKED_CACHE_KEEP = 1,
+	UNTRACKED_CACHE_WRITE = 2
+};
+
 struct repo_settings {
 	int initialized;
 
@@ -18,6 +25,7 @@ struct repo_settings {
 	int gc_write_commit_graph;
 
 	int index_version;
+	enum untracked_cache_setting core_untracked_cache;
 
 	int pack_use_sparse;
 };