Support 'push --dry-run' for http transport If the end-user requested a dry-run push we need to pass that flag over to http-push and additionally make sure it does not actually upload any changes to the remote server. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

diff --git a/Documentation/git-http-push.txt b/Documentation/git-http-push.txt
index 9afb860..3a69b71 100644
--- a/Documentation/git-http-push.txt
+++ b/Documentation/git-http-push.txt

@@ -8,7 +8,7 @@
 
 SYNOPSIS
 --------
-'git-http-push' [--all] [--force] [--verbose] <url> <ref> [<ref>...]
+'git-http-push' [--all] [--dry-run] [--force] [--verbose] <url> <ref> [<ref>...]
 
 DESCRIPTION
 -----------
@@ -30,6 +30,9 @@
 	the remote repository can lose commits; use it with
 	care.
 
+--dry-run::
+	Do everything except actually send the updates.
+
 --verbose::
 	Report the list of objects being walked locally and the
 	list of objects successfully sent to the remote repository.

diff --git a/http-push.c b/http-push.c
index a035919..c02a3af 100644
--- a/http-push.c
+++ b/http-push.c

@@ -13,7 +13,7 @@
 #include <expat.h>
 
 static const char http_push_usage[] =
-"git-http-push [--all] [--force] [--verbose] <remote> [<head>...]\n";
+"git-http-push [--all] [--dry-run] [--force] [--verbose] <remote> [<head>...]\n";
 
 #ifndef XML_STATUS_OK
 enum XML_Status {
@@ -80,6 +80,7 @@
 static int push_verbosely;
 static int push_all;
 static int force_all;
+static int dry_run;
 
 static struct object_list *objects;
 
@@ -2302,6 +2303,10 @@
 				force_all = 1;
 				continue;
 			}
+			if (!strcmp(arg, "--dry-run")) {
+				dry_run = 1;
+				continue;
+			}
 			if (!strcmp(arg, "--verbose")) {
 				push_verbosely = 1;
 				continue;
@@ -2443,7 +2448,8 @@
 		if (strcmp(ref->name, ref->peer_ref->name))
 			fprintf(stderr, " using '%s'", ref->peer_ref->name);
 		fprintf(stderr, "\n  from %s\n  to   %s\n", old_hex, new_hex);
-
+		if (dry_run)
+			continue;
 
 		/* Lock remote branch ref */
 		ref_lock = lock_remote(ref->name, LOCK_TIME);
@@ -2511,7 +2517,8 @@
 	if (remote->has_info_refs && new_refs) {
 		if (info_ref_lock && remote->can_update_info_refs) {
 			fprintf(stderr, "Updating remote server info\n");
-			update_remote_info_refs(info_ref_lock);
+			if (!dry_run)
+				update_remote_info_refs(info_ref_lock);
 		} else {
 			fprintf(stderr, "Unable to update server info\n");
 		}

diff --git a/transport.c b/transport.c
index f34d197..400af71 100644
--- a/transport.c
+++ b/transport.c

@@ -392,6 +392,8 @@
 		argv[argc++] = "--all";
 	if (flags & TRANSPORT_PUSH_FORCE)
 		argv[argc++] = "--force";
+	if (flags & TRANSPORT_PUSH_DRY_RUN)
+		argv[argc++] = "--dry-run";
 	argv[argc++] = transport->url;
 	while (refspec_nr--)
 		argv[argc++] = *refspec++;