Sandbox version

Code Result
((braces/sandbox)) (())
((braces/sandbox |Templatename)) ((Templatename))
((braces/sandbox |Templatename|item1|item2|item3)) ((Templatename|item1|item2|item3))
((braces/sandbox|code=on |Templatename|item1)) ((Templatename|item1))
((braces/sandbox |Templatename|item1((=))ABC|item2((=))DEF)) ((Templatename|item1=ABC|item2=DEF))
((braces/sandbox|code=on |Templatename|item1=ABC|item2=DEF)) ((Templatename))

Main template

Code Result
((braces)) (())
((braces |Templatename)) ((Templatename))
((braces |Templatename|item1|item2|item3)) ((Templatename|item1|item2|item3))
((braces|code=on |Templatename|item1)) ((Templatename|item1))
((braces |Templatename|item1((=))ABC|item2((=))DEF)) ((Templatename|item1=ABC|item2=DEF))
((braces|code=on |Templatename|item1=ABC|item2=DEF)) ((Templatename))