[CMake] CMake list and Single square brackets

[t m]

Hello All,

Can anyone explain me why in the 3rd call of message function the
following code will return 1 instead of 2

cmake_minimum_required( VERSION 2.6 )

set (_list)
set (_list "foo;bar")# 2 items
list (LENGTH _list _len)
message (STATUS "_len=${_len}")# 2

set (_list)
set (_list "foo[];bar")#2 items
list (LENGTH _list _len)
message (STATUS "_len=${_len}")# 2

set (_list)
list(APPEND _list "foo]" "bar")#2 items
list (LENGTH _list _len)
message (STATUS "_len=${_len}")#1

Can I miss something in the documentation or this is a bug ?

regards, Tomek.