diamond: add canonical data

[stkent]

Closes #556. See that issue for background information. Please contribute any new comments in this PR. Thanks!

I'm far from a property-based testing expert, so my explanation in the test data comment is likely clumsy. Please feel free to explain how to refine it!

I attempted to follow the proposed canonical data spec from #602. If you spot any deviations from the proposal, please let me know and I can correct them. cc @rbasso for his expertise and validation 😄

[rbasso]

I didn't followed the discussion about the tests' contents, so I'm reviewing just the format.

I attempted to follow the proposed canonical data spec from #602. If you spot any deviations from the proposal, please let me know and I can correct them. cc @rbasso for his expertise and validation 😄

I just validated the canonical-data.json file here, so it is formally correct.

[stkent]

@rbasso thanks! 👍 @ spec!

[ErikSchierboom]

@stkent Do you want to modify the canonical-data of this PR (e.g. due to the discussion in #614), or shall we merge it?

[stkent]

@ErikSchierboom sorry, I don't quite follow; what was the modification you had in mind? Thanks!

[ErikSchierboom]

@stkent Oh sorry, I meant the bit about "print". There was some discussion if "print" was a good name, as it might imply that we were printing to the console instead of returning a string.

[stkent]

Ah, I'm with you now. Yes, let's change that - easy fix at this point. Incoming!

[stkent]

@ErikSchierboom I updated print to rows, but I'm open to other suggestions if that's not clear enough. (I'm thinking that with an updated description and the expected output as context, it should be ok?)

[ErikSchierboom]

@stkent I think rows is a good choice. 👍