fetch-pack: use a separate flag for fetch in deepening mode

The shallow repo could be deepened or shortened when then user gives
--depth. But in future that won't be the only way to deepen/shorten a
repo. Stop relying on args->depth in this mode. Future deepening
methods can simply set this flag on instead of updating all these if
expressions.

The new name "deepen" was chosen after the command to define shallow
boundary in pack protocol. New commands also follow this tradition.

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

fetch-pack.c

diff --git a/fetch-pack.c b/fetch-pack.c
index 08caf1d..a14d24a 100644
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -197,7 +197,7 @@
 
 static void consume_shallow_list(struct fetch_pack_args *args, int fd)
 {
-	if (args->stateless_rpc && args->depth > 0) {
+	if (args->stateless_rpc && args->deepen) {
 		/* If we sent a depth we will get back "duplicate"
 		 * shallow and unshallow commands every time there
 		 * is a block of have lines exchanged.
@@ -348,7 +348,7 @@
 	packet_buf_flush(&req_buf);
 	state_len = req_buf.len;
 
-	if (args->depth > 0) {
+	if (args->deepen) {
 		char *line;
 		const char *arg;
 		unsigned char sha1[20];
@@ -557,7 +557,7 @@
 		}
 
 		if (!keep && args->fetch_all &&
-		    (!args->depth || !starts_with(ref->name, "refs/tags/")))
+		    (!args->deepen || !starts_with(ref->name, "refs/tags/")))
 			keep = 1;
 
 		if (keep) {
@@ -627,7 +627,7 @@
 		}
 	}
 
-	if (!args->depth) {
+	if (!args->deepen) {
 		for_each_ref(mark_complete_oid, NULL);
 		for_each_alternate_ref(mark_alternate_complete, NULL);
 		commit_list_sort_by_date(&complete);
@@ -812,6 +812,8 @@
 
 	if ((args->depth > 0 || is_repository_shallow()) && !server_supports("shallow"))
 		die(_("Server does not support shallow clients"));
+	if (args->depth > 0)
+		args->deepen = 1;
 	if (server_supports("multi_ack_detailed")) {
 		print_verbose(args, _("Server supports multi_ack_detailed"));
 		multi_ack = 2;
@@ -872,7 +874,7 @@
 
 	if (args->stateless_rpc)
 		packet_flush(fd[1]);
-	if (args->depth > 0)
+	if (args->deepen)
 		setup_alternate_shallow(&shallow_lock, &alternate_shallow_file,
 					NULL);
 	else if (si->nr_ours || si->nr_theirs)
@@ -939,7 +941,7 @@
 	int *status;
 	int i;
 
-	if (args->depth > 0 && alternate_shallow_file) {
+	if (args->deepen && alternate_shallow_file) {
 		if (*alternate_shallow_file == '\0') { /* --unshallow */
 			unlink_or_warn(git_path_shallow());
 			rollback_lock_file(&shallow_lock);

fetch-pack.h

diff --git a/fetch-pack.h b/fetch-pack.h
index bb7fd76..4d0adb0 100644
--- a/fetch-pack.h
+++ b/fetch-pack.h
@@ -25,6 +25,7 @@
 	unsigned self_contained_and_connected:1;
 	unsigned cloning:1;
 	unsigned update_shallow:1;
+	unsigned deepen:1;
 };
 
 /*