push: respect --no-thin

- From the beginning of push.c in 755225d, 2006-04-29, "thin" option
  was enabled by default but could be turned off with --no-thin.

- Then Shawn changed the default to 0 in favor of saving server
  resources in a4503a1, 2007-09-09. --no-thin worked great.

- One day later, in 9b28851 Daniel extracted some code from push.c to
  create transport.c. He (probably accidentally) flipped the default
  value from 0 to 1 in transport_get().

From then on --no-thin is effectively no-op because git-push still
expects the default value to be false and only calls
transport_set_option() when "thin" variable in push.c is true (which
is unnecessary). Correct the code to respect --no-thin by calling
transport_set_option() in both cases.

receive-pack learns about --reject-thin-pack-for-testing option,
which only is for testing purposes, hence no document update.

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

builtin/push.c

@@ -15,7 +15,7 @@ static const char * const push_usage[] = {
 	NULL,
 };
 
-static int thin;
+static int thin = 1;
 static int deleterefs;
 static const char *receivepack;
 static int verbosity;
@@ -313,8 +313,7 @@ static int push_with_options(struct transport *transport, int flags)
 	if (receivepack)
 		transport_set_option(transport,
 				     TRANS_OPT_RECEIVEPACK, receivepack);
-	if (thin)
-		transport_set_option(transport, TRANS_OPT_THIN, "yes");
+	transport_set_option(transport, TRANS_OPT_THIN, thin ? "yes" : NULL);
 
 	if (verbosity > 0)
 		fprintf(stderr, _("Pushing to %s\n"), transport->url);

builtin/receive-pack.c

@@ -38,6 +38,7 @@ static int quiet;
 static int prefer_ofs_delta = 1;
 static int auto_update_server_info;
 static int auto_gc = 1;
+static int fix_thin = 1;
 static const char *head_name;
 static void *head_name_to_free;
 static int sent_capabilities;
@@ -869,7 +870,8 @@ static const char *unpack(int err_fd)
 		keeper[i++] = "--stdin";
 		if (fsck_objects)
 			keeper[i++] = "--strict";
-		keeper[i++] = "--fix-thin";
+		if (fix_thin)
+			keeper[i++] = "--fix-thin";
 		keeper[i++] = hdr_arg;
 		keeper[i++] = keep_arg;
 		keeper[i++] = NULL;
@@ -975,6 +977,10 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 				stateless_rpc = 1;
 				continue;
 			}
+			if (!strcmp(arg, "--reject-thin-pack-for-testing")) {
+				fix_thin = 0;
+				continue;
+			}
 
 			usage(receive_pack_usage);
 		}

t/t5516-fetch-push.sh

@@ -1172,4 +1172,21 @@ test_expect_success 'push --follow-tag only pushes relevant tags' '
 	test_cmp expect actual
 '
 
+test_expect_success 'push --no-thin must produce non-thin pack' '
+	cat >>path1 <<\EOF &&
+keep base version of path1 big enough, compared to the new changes
+later, in order to pass size heuristics in
+builtin/pack-objects.c:try_delta()
+EOF
+	git commit -am initial &&
+	git init no-thin &&
+	git --git-dir=no-thin/.git config receive.unpacklimit 0 &&
+	git push no-thin/.git refs/heads/master:refs/heads/foo &&
+	echo modified >> path1 &&
+	git commit -am modified &&
+	git repack -adf &&
+	rcvpck="git receive-pack --reject-thin-pack-for-testing" &&
+	git push --no-thin --receive-pack="$rcvpck" no-thin/.git refs/heads/master:refs/heads/foo
+'
+
 test_done