fetch: lift up parsing of "fetch.output" config variable

Parsing the display format happens inside of `display_state_init()`. As
we only need to check for a simple config entry, this is a natural
location to put this code as it means that display-state logic is neatly
contained in a single location.

We're about to introduce a new "porcelain" output format though that is
intended to be parseable by machines, for example inside of a script.
This format can be enabled by passing the `--porcelain` switch to
git-fetch(1). As a consequence, we'll have to add a second callsite that
influences the output format, which will become awkward to handle.

Refactor the code such that callers are expected to pass the display
format that is to be used into `display_state_init()`. This allows us to
lift up the code into the main function, where we can then hook it into
command line options parser in a follow-up commit.

Signed-off-by: Patrick Steinhardt <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: pks-t

builtin/fetch.c

@@ -106,8 +106,14 @@ static int fetch_write_commit_graph = -1;
 static int stdin_refspecs = 0;
 static int negotiate_only;
 
+struct fetch_config {
+	enum display_format display_format;
+};
+
 static int git_fetch_config(const char *k, const char *v, void *cb)
 {
+	struct fetch_config *fetch_config = cb;
+
 	if (!strcmp(k, "fetch.prune")) {
 		fetch_prune_config = git_config_bool(k, v);
 		return 0;
@@ -146,6 +152,18 @@ static int git_fetch_config(const char *k, const char *v, void *cb)
 		return 0;
 	}
 
+	if (!strcmp(k, "fetch.output")) {
+		if (!v)
+			return config_error_nonbool(k);
+		else if (!strcasecmp(v, "full"))
+			fetch_config->display_format = DISPLAY_FORMAT_FULL;
+		else if (!strcasecmp(v, "compact"))
+			fetch_config->display_format = DISPLAY_FORMAT_COMPACT;
+		else
+			die(_("invalid value for '%s': '%s'"),
+			    "fetch.output", v);
+	}
+
 	return git_default_config(k, v, cb);
 }
 
@@ -802,14 +820,13 @@ static int refcol_width(const struct ref *ref_map, int compact_format)
 }
 
 static void display_state_init(struct display_state *display_state, struct ref *ref_map,
-			       const char *raw_url)
+			       const char *raw_url, enum display_format format)
 {
-	const char *format = "full";
 	int i;
 
 	memset(display_state, 0, sizeof(*display_state));
-
 	strbuf_init(&display_state->buf, 0);
+	display_state->format = format;
 
 	if (raw_url)
 		display_state->url = transport_anonymize_url(raw_url);
@@ -826,15 +843,6 @@ static void display_state_init(struct display_state *display_state, struct ref *
 	if (verbosity < 0)
 		return;
 
-	git_config_get_string_tmp("fetch.output", &format);
-	if (!strcasecmp(format, "full"))
-		display_state->format = DISPLAY_FORMAT_FULL;
-	else if (!strcasecmp(format, "compact"))
-		display_state->format = DISPLAY_FORMAT_COMPACT;
-	else
-		die(_("invalid value for '%s': '%s'"),
-		    "fetch.output", format);
-
 	switch (display_state->format) {
 	case DISPLAY_FORMAT_FULL:
 	case DISPLAY_FORMAT_COMPACT:
@@ -1608,7 +1616,8 @@ static int backfill_tags(struct display_state *display_state,
 }
 
 static int do_fetch(struct transport *transport,
-		    struct refspec *rs)
+		    struct refspec *rs,
+		    enum display_format display_format)
 {
 	struct ref_transaction *transaction = NULL;
 	struct ref *ref_map = NULL;
@@ -1694,7 +1703,7 @@ static int do_fetch(struct transport *transport,
 	if (retcode)
 		goto cleanup;
 
-	display_state_init(&display_state, ref_map, transport->url);
+	display_state_init(&display_state, ref_map, transport->url, display_format);
 
 	if (atomic_fetch) {
 		transaction = ref_transaction_begin(&err);
@@ -2077,7 +2086,8 @@ static inline void fetch_one_setup_partial(struct remote *remote)
 }
 
 static int fetch_one(struct remote *remote, int argc, const char **argv,
-		     int prune_tags_ok, int use_stdin_refspecs)
+		     int prune_tags_ok, int use_stdin_refspecs,
+		     enum display_format display_format)
 {
 	struct refspec rs = REFSPEC_INIT_FETCH;
 	int i;
@@ -2144,7 +2154,7 @@ static int fetch_one(struct remote *remote, int argc, const char **argv,
 	sigchain_push_common(unlock_pack_on_signal);
 	atexit(unlock_pack_atexit);
 	sigchain_push(SIGPIPE, SIG_IGN);
-	exit_code = do_fetch(gtransport, &rs);
+	exit_code = do_fetch(gtransport, &rs, display_format);
 	sigchain_pop(SIGPIPE);
 	refspec_clear(&rs);
 	transport_disconnect(gtransport);
@@ -2154,6 +2164,9 @@ static int fetch_one(struct remote *remote, int argc, const char **argv,
 
 int cmd_fetch(int argc, const char **argv, const char *prefix)
 {
+	struct fetch_config config = {
+		.display_format = DISPLAY_FORMAT_FULL,
+	};
 	int i;
 	const char *bundle_uri;
 	struct string_list list = STRING_LIST_INIT_DUP;
@@ -2173,7 +2186,7 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 		free(anon);
 	}
 
-	git_config(git_fetch_config, NULL);
+	git_config(git_fetch_config, &config);
 	if (the_repository->gitdir) {
 		prepare_repo_settings(the_repository);
 		the_repository->settings.command_requires_full_index = 0;
@@ -2310,7 +2323,8 @@ int cmd_fetch(int argc, const char **argv, const char *prefix)
 	} else if (remote) {
 		if (filter_options.choice || repo_has_promisor_remote(the_repository))
 			fetch_one_setup_partial(remote);
-		result = fetch_one(remote, argc, argv, prune_tags_ok, stdin_refspecs);
+		result = fetch_one(remote, argc, argv, prune_tags_ok, stdin_refspecs,
+				   config.display_format);
 	} else {
 		int max_children = max_jobs;