Allow rejection of NaN and Inf float values on encode and decode.

[benluddy]

Description

Implements #512 to allow users to error rather than encode or decode NaN and Inf floating-point values.

PR Was Proposed and Welcomed in Currently Open Issue

• This PR was proposed and welcomed by maintainer(s) in issue #___
• Closes or Updates Issue feature: Options to reject floating-point NaN and Inf values on encode and decode #512

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[fxamacker]

@benluddy Thanks for opening this PR! It makes sense to add options to reject NaN and infinity for some use cases.

Encoding looks great!

For decoding, we can probably handle decoding options similar to way it is done for TagsMode and IndefLengthMode:

• Handle new decoding options in wellformedl() instead of decoding functions, so codec can reject CBOR data early without allocating decoded objects. It would also simplify decoding function because wellformed() is called before parseToValue().

• Use the same naming convention (e.g. TagsMode has options TagsAllowed and TagsForbidden).

Thoughts?

[benluddy]

Thoughts?

Sounds great. I had been thinking to myself, "what if a user needs to distinguish between ill-formed input and well-formed input that is rejected by the application's protocol." Now I realize that that case can be served just fine by a second call to Wellformed using a permissive decode mode on error cases.

I'll implement your recommendations today.

[benluddy]

I'll implement your recommendations today.

Done. Please take another look when you have a chance.

[fxamacker]

Thanks for updating this PR! I left some comments about checking CBOR type before converting to float.

[benluddy]

D'oh! Thank you. Added test cases to catch that and fixed.

[fxamacker]

Nice! 👍 Thanks for updating this PR!