closes #1883, no upgrade script #successkid

public/src/forum/admin/groups.js

@@ -80,7 +80,7 @@ define('forum/admin/groups', ['forum/admin/iconSelect'], function(iconSelect) {
 				socket.emit('admin.groups.get', groupName, function(err, groupObj) {
 					var formEl = detailsModal.find('form');
 
-					formEl.find('#change-group-name').val(groupObj.name);
+					formEl.find('#change-group-name').val(groupObj.name).prop('readonly', groupObj.system);
 					formEl.find('#change-group-desc').val(groupObj.description);
 					formEl.find('#change-group-user-title').val(groupObj.userTitle);
 					formEl.find('#group-icon').attr('class', 'fa fa-2x ' + groupObj.icon).attr('value', groupObj.icon);

src/groups.js

@@ -244,10 +244,79 @@
 				icon: values.icon || '',
 				labelColor: values.labelColor || '#000000',
 				hidden: values.hidden || '0'
-			}, callback);
+			}, function(err) {
+				if (err) {
+					return callback(err);
+				}
+
+				renameGroup(groupName, values.name, callback);
+			});
 		});
 	};
 
+	function renameGroup(oldName, newName, callback) {
+		if (oldName === newName || newName.length === 0) {
+			return callback();
+		}
+
+		db.getObject('group:' + oldName, function(err, group) {
+			if (err || !group) {
+				return callback(err);
+			}
+
+			if (parseInt(group.system, 10) === 1 || parseInt(group.hidden, 10) === 1) {
+				return callback();
+			}
+
+			Groups.exists(newName, function(err, exists) {
+				if (err || exists) {
+					return callback(err || new Error('[[error:group-already-exists]]'));
+				}
+
+				async.series([
+					function(next) {
+						db.setObjectField('group:' + oldName, 'name', newName, next);
+					},
+					function(next) {
+						db.getSetMembers('groups', function(err, groups) {
+							if (err) {
+								return next(err);
+							}
+							async.each(groups, function(group, next) {
+								renameGroupMember('group:' + group + ':members', oldName, newName, next);
+							}, next);
+						});
+					},
+					function(next) {
+						db.rename('group:' + oldName, 'group:' + newName, next);
+					},
+					function(next) {
+						db.rename('group:' + oldName + ':members', 'group:' + newName + ':members', next);
+					},
+					function(next) {
+						renameGroupMember('groups', oldName, newName, next);
+					}
+				], callback);
+			});
+		});
+	}
+
+	function renameGroupMember(group, oldName, newName, callback) {
+		db.isSetMember(group, oldName, function(err, isMember) {
+			if (err || !isMember) {
+				return callback(err);
+			}
+			async.series([
+				function (next) {
+					db.setRemove(group, oldName, next);
+				},
+				function (next) {
+					db.setAdd(group, newName, next);
+				}
+			], callback);
+		});
+	}
+
 	Groups.destroy = function(groupName, callback) {
 		async.parallel([
 			function(next) {