Incompatibility with other implementations

[bucko13]

I've been using this library in a project of mine lsat-js which is an authentication scheme that leverages macaroons. It's been great so far, especially with the TS support.

Unfortunately, I ran into a problem when interacting with other libraries. It was discovered recently that certain macaroons were unable to be decoded by the lsat-js library that were originally encoded in and able to be decoded by other implementations.

With this sample base64 encoded macaroon:

AgESMy4xMzYuMTc4LjE1OjM0MjM4AkIAAD2b0rX78LATiVo8bKgHuurefeF5OeX2H5ZuacBIK3+RAR1PKU1oZpfCZFib4zdDoj0pOpgPmhtuzNllU+y//D0AAAYgcWFs9FIteCzpCcEPSwmXKBpcx97hyL5Yt99cbLjRHzU=

I am able to decode in this js macaroon implementation (link) which maintains compatibility with several other implementations. This was also generated and verified in a golang package.

Unfortunately, using MacaroonsBuilder.deserialize I get this error (with stack trace):

     RangeError [ERR_INVALID_OPT_VALUE]: The value "-1" is invalid for option "size"
      at Function.alloc (buffer.js:278:3)
      at Function.MacaroonsDeSerializer.readPacket (node_modules/macaroons.js/lib/MacaroonsDeSerializer.js:87:27)
      at Function.MacaroonsDeSerializer.deserializeStream (node_modules/macaroons.js/lib/MacaroonsDeSerializer.js:25:58)
      at Function.MacaroonsDeSerializer.deserialize (node_modules/macaroons.js/lib/MacaroonsDeSerializer.js:16:38)
      at Function.MacaroonsBuilder.deserialize (node_modules/macaroons.js/lib/MacaroonsBuilder.js:33:38)

I was wondering if this was a known incompatibility if maybe the split from the specs was deliberate, and if not if there was some way to patch it?

It does look like there's a comment to catch the type of situation that's happening here (see here) but it's not getting caught and the buffer is allocated with size of -1.

Thanks!

[bucko13]

Just saw this closed issue and thinking perhaps it's related:
#10

Any chance of having an option where it can be brought into compatibility?

[bucko13]

Sorry, I was digging a little more and I'm not convinced this is entirely related to the issue linked above (#10) because looking into the macaroon.js implementation that is able to deserialize the macaroon above, it appears to also work in URL safe base64 (see here) but it's possible I'm missing something.