push: parse and set flag for "--force-if-includes"

The previous commit added the necessary machinery to implement the
"--force-if-includes" protection, when "--force-with-lease" is used
without giving exact object the remote still ought to have. Surface
the feature by adding a command line option and a configuration
variable to enable it.

 - Add a flag: "TRANSPORT_PUSH_FORCE_IF_INCLUDES" to indicate that the
   new option was passed from the command line of via configuration
   settings; update command line and configuration parsers to set the
   new flag accordingly.

 - Introduce a new configuration option "push.useForceIfIncludes", which
   is equivalent to setting "--force-if-includes" in the command line.

 - Update "remote-curl" to recognize and pass this option to "send-pack"
   when enabled.

 - Update "advise" to catch the reject reason "REJECT_REF_NEEDS_UPDATE",
   set when the ref status is "REF_STATUS_REJECT_REMOTE_UPDATED" and
   (optionally) print a help message when the push fails.

 - The new option is a "no-op" in the following scenarios:
    * When used without "--force-with-lease".
    * When used with "--force-with-lease", and if the expected commit
      on the remote side is specified as an argument.

Signed-off-by: Srinidhi Kaushik <shrinidhi.kaushik@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/remote-curl.c b/remote-curl.c
index 32cc4a0c55..0290b04891 100644
--- a/remote-curl.c
+++ b/remote-curl.c
@@ -44,7 +44,8 @@ struct options {
 		from_promisor : 1,
 
 		atomic : 1,
-		object_format : 1;
+		object_format : 1,
+		force_if_includes : 1;
 	const struct git_hash_algo *hash_algo;
 };
 static struct options options;
@@ -131,6 +132,14 @@ static int set_option(const char *name, const char *value)
 		string_list_append(&cas_options, val.buf);
 		strbuf_release(&val);
 		return 0;
+	} else if (!strcmp(name, TRANS_OPT_FORCE_IF_INCLUDES)) {
+		if (!strcmp(value, "true"))
+			options.force_if_includes = 1;
+		else if (!strcmp(value, "false"))
+			options.force_if_includes = 0;
+		else
+			return -1;
+		return 0;
 	} else if (!strcmp(name, "cloning")) {
 		if (!strcmp(value, "true"))
 			options.cloning = 1;
@@ -1318,6 +1327,9 @@ static int push_git(struct discovery *heads, int nr_spec, const char **specs)
 		strvec_push(&args, cas_option->string);
 	strvec_push(&args, url.buf);
 
+	if (options.force_if_includes)
+		strvec_push(&args, "--force-if-includes");
+
 	strvec_push(&args, "--stdin");
 	for (i = 0; i < nr_spec; i++)
 		packet_buf_write(&preamble, "%s\n", specs[i]);