branch: add --unset-upstream option

We have ways of setting the upstream information, but if we want to
unset it, we need to resort to modifying the configuration manually.

Teach branch an --unset-upstream option that unsets this information.

Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 18 insertions, 3 deletions

diff --git a/builtin/branch.c b/builtin/branch.c
index 3c978eb18..557995d97 100644
--- a/builtin/branch.c
+++ b/builtin/branch.c
@@ -712,7 +712,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	int delete = 0, rename = 0, force_create = 0, list = 0;
 	int verbose = 0, abbrev = -1, detached = 0;
 	int reflog = 0, edit_description = 0;
-	int quiet = 0;
+	int quiet = 0, unset_upstream = 0;
 	const char *new_upstream = NULL;
 	enum branch_track track;
 	int kinds = REF_LOCAL_BRANCH;
@@ -728,6 +728,7 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		OPT_SET_INT( 0, "set-upstream",  &track, "change upstream info",
 			BRANCH_TRACK_OVERRIDE),
 		OPT_STRING('u', "set-upstream-to", &new_upstream, "upstream", "change the upstream info"),
+		OPT_BOOLEAN(0, "unset-upstream", &unset_upstream, "Unset the upstream info"),
 		OPT__COLOR(&branch_use_color, "use colored output"),
 		OPT_SET_INT('r', "remotes",     &kinds, "act on remote-tracking branches",
 			REF_REMOTE_BRANCH),
@@ -796,10 +797,10 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 	argc = parse_options(argc, argv, prefix, options, builtin_branch_usage,
 			     0);
 
-	if (!delete && !rename && !edit_description && !new_upstream && argc == 0)
+	if (!delete && !rename && !edit_description && !new_upstream && !unset_upstream && argc == 0)
 		list = 1;
 
-	if (!!delete + !!rename + !!force_create + !!list + !!new_upstream > 1)
+	if (!!delete + !!rename + !!force_create + !!list + !!new_upstream + !!unset_upstream > 1)
 		usage_with_options(builtin_branch_usage, options);
 
 	if (abbrev == -1)
@@ -865,6 +866,20 @@ int cmd_branch(int argc, const char **argv, const char *prefix)
 		 * info and making sure new_upstream is correct
 		 */
 		create_branch(head, branch->name, new_upstream, 0, 0, 0, quiet, BRANCH_TRACK_OVERRIDE);
+	} else if (unset_upstream) {
+		struct branch *branch = branch_get(argv[0]);
+		struct strbuf buf = STRBUF_INIT;
+
+		if (!branch_has_merge_config(branch)) {
+			die(_("Branch '%s' has no upstream information"), branch->name);
+		}
+
+		strbuf_addf(&buf, "branch.%s.remote", branch->name);
+		git_config_set_multivar(buf.buf, NULL, NULL, 1);
+		strbuf_reset(&buf);
+		strbuf_addf(&buf, "branch.%s.merge", branch->name);
+		git_config_set_multivar(buf.buf, NULL, NULL, 1);
+		strbuf_release(&buf);
 	} else if (argc > 0 && argc <= 2) {
 		if (kinds != REF_LOCAL_BRANCH)
 			die(_("-a and -r options to 'git branch' do not make sense with a branch name"));