Leave a branch spelled like an option out of the switcher

Such a name is refused as a head before git could read it as an
option, and the fallback branch already skips it, so the switcher
offered a choice that led only to an error page.

2 files changed, 11 insertions, 0 deletions

diff --git a/source/ui-shared.c b/source/ui-shared.c
index 147472e..3970c58 100644
--- a/source/ui-shared.c
+++ b/source/ui-shared.c
@@ -480,6 +480,10 @@ static int print_branch_option(const struct reference *ref, void *data)
 	// The switcher runs on every page, so it is bounded like the refs list.
 	if (ctx.cfg.max_ref_count && opt->count >= ctx.cfg.max_ref_count)
 		return -1;
+	// A name spelled like an option is refused as a head, so offering it
+	// would only lead to an error page.
+	if (name[0] == '-')
+		return 0;
 	opt->count++;
 	html_option(name, name, opt->selected);
 	return 0;
diff --git a/tests/t0303-robustness.sh b/tests/t0303-robustness.sh
index 5bdb060..55a83c3 100755
--- a/tests/t0303-robustness.sh
+++ b/tests/t0303-robustness.sh
@@ -382,6 +382,13 @@ test_expect_success 'the fallback branch skips a name spelled like an option' '
 	grep "^Status: 200" tmp
 '
 
+# Such a branch is refused as a head, so the switcher must not offer a
+# choice that can only lead to an error page.
+test_expect_success 'the branch switcher leaves out a name spelled like an option' '
+	grep "<option value=.master." tmp &&
+	! grep "<option value=.-first." tmp
+'
+
 test_expect_success 'a blank line in the mimetype file is skipped' '
 	(
 		cd repos/rob &&