[Notts Police] Allow staff to manage available states

For FD-4703

perllib/FixMyStreet/Cobrand/NottinghamshirePolice.pm

@@ -190,4 +190,36 @@ sub example_places {
     return [ 'NG2 3DZ', 'Meadows Way, Nottingham' ];
 }
 
+=head2 available_permissions
+
+Add the manage_states permission to the list of available permissions.
+
+=cut
+
+sub available_permissions {
+    my $self = shift;
+    my $perms = $self->next::method();
+    $perms->{Problems}->{manage_states} = "Add/remove states";
+    return $perms;
+}
+
+=head2 admin_pages
+
+Users with the manage_states permission can access the states admin page.
+
+=cut
+
+sub admin_pages {
+    my $self = shift;
+    my $pages = $self->next::method();
+
+    if ( $self->{c}->user->has_body_permission_to('manage_states') ) {
+        $pages->{states} = [ _('States'), 102 ];
+    };
+
+    return $pages;
+}
+
+
+
 1;

t/cobrand/nottinghamshirepolice.t

@@ -94,6 +94,25 @@ FixMyStreet::override_config {
         $report->discard_changes;
         is $report->get_extra_metadata('sent_to_council'), 'Gedling Borough Council';
     };
+
+    subtest 'check new permission is available' => sub {
+        $mech->log_in_ok($staff->email);
+        $staff->user_body_permissions->create({ body => $notts_police, permission_type => 'user_edit' });
+        $staff->user_body_permissions->create({ body => $notts_police, permission_type => 'user_manage_permissions' });
+
+        $mech->get("/admin/users/" . $staff->id);
+        $mech->content_contains('Add/remove states');
+    };
+
+    subtest 'check states page behind permission' => sub {
+        $mech->log_in_ok($staff->email);
+
+        $mech->get("/admin/states");
+        is $mech->status, 404, "Staff user can't access states page without permission";
+
+        $staff->user_body_permissions->create({ body => $notts_police, permission_type => 'manage_states' });
+        $mech->get_ok("/admin/states");
+    };
 };
 
 subtest 'Permissions for report updates' => sub {