Truffle Decoder's second parameter of dependent contracts should be optional

Calling this:

const decoder = await Decoder.forContractInstance(truffleContractInstance);

Produces a cryptic error:

TypeError: Cannot read property 'includes' of undefined
    at index.js:374
    at step (index.js:261)
    at Object.next (index.js:192)
    at index.js:164
...

It is only when you pass in an empty array as the second parameter does the error go away:

const decoder = await Decoder.forContractInstance(truffleContractInstance, []);

[haltman-at]

So, looking at the two issues you submitted, the conclusion I’m coming to is that I didn’t really optimize this for convenience in this just-a-simple-contract case, where there are no external structs or enums or contract types you need to deal with, no inheritance, you’re not decoding events of unknown provenance, etc. I was really focused on the opposite case (which I realize is not exactly convenient at the moment, but I was planning to make it so eventually). But, I guess I can largely address that by the means you suggest, of making that argument optional and treating it as []. So, whew, problem avoided there.

[haltman-at]

Oh, huh, why is this still open? Closing.