TypeError: Cannot read property 'length' of undefined

[christianbundy]

I see this pretty often on Travis.

/home/travis/build/ssbc/ssb-tribes/node_modules/envelope-js/util/derive-secret.js:17
    if (info.some(i => i.length === 0)) {
                         ^

TypeError: Cannot read property 'length' of undefined
    at /home/travis/build/ssbc/ssb-tribes/node_modules/envelope-js/util/derive-secret.js:17:26
    at Array.some (<anonymous>)
    at derive (/home/travis/build/ssbc/ssb-tribes/node_modules/envelope-js/util/derive-secret.js:17:14)
    at box (/home/travis/build/ssbc/ssb-tribes/node_modules/envelope-js/box.js:15:20)
    at groupCreate (/home/travis/build/ssbc/ssb-tribes/method/group/init.js:34:22)
    at Timeout._onTimeout (/home/travis/build/ssbc/ssb-tribes/method/index.js:21:54)
    at listOnTimeout (internal/timers.js:549:17)
    at processTimers (internal/timers.js:492:7)