Thanks for working on this! 🙂
I just left a small comment about leveraging NodeCrypto as well.

I've added tests but I'm not sure if I should add more tests using a PGP key which uses SHA3 internally. What do you think? If you think that I should, where do you think I should add that test?

I would add a test checking that

• a key using SHA3 internal signatures can be read using openpgp.readKey (e.g. key from #1663 (comment) )
• signing with the key (using openpgp.sign) generates a sha3 signature
• the newly generated SHA3 signature is verified (by openpgp.verify)

This could go under the unit tests for signing in test/general/openpgpjs.js.

Since SHA3 is just another hash algo, I don't think more ad-hoc tests are needed: everything is expected to work as long as the underlying hash function is correct.

Thanks for the prompt changes! Almost there, just noted a couple of minor things 🙂 (in particular, see #1680 (comment) ).

Thanks again! Looks good to me, let's see if @twiss has something to add 🙂

Thanks for working on this! It looks good to me. Just as a note, we may want to consider adding these algorithms to the preferred hash algorithms (in key/factory.js) as well, but before we do that we should do some benchmarks on which algorithms are fastest, to decide the order. So IMO we can merge this as-is and do that later :)