is $b, 'y', 'array: pop correctly';
check { unshift @a, 'z'; () }
{ set => 1, (len => 1) x !VMG_COMPAT_ARRAY_UNSHIFT_NOLEN_VOID },
'unshift (void)';
is $b, 'y', 'array: pop correctly';
check { unshift @a, 'z'; () }
{ set => 1, (len => 1) x !VMG_COMPAT_ARRAY_UNSHIFT_NOLEN_VOID },
'unshift (void)';