added eq, partialeq trait for operator equality comparison

[thesuhas]

Hi,

I have a use case where I would need to compare different Operator enum instances in wasmparser to see if they are the same one. It helps me traverse a .wat file and identify if a particular Operator that I am at is the desired one.

I've added the Eq and PartialEq trait to Operator and all its dependencies to enable this in a clean and easy way.

[alexcrichton]

Thanks! The one type I'd hesitate on though is the BinaryReader type, Could that be removed instead? If that only affects BrTable could the BrTable type have a manual Eq implementation?

[thesuhas]

I can do that! To implement Eq for BrTable, how would I compare the BinaryReader? Additionally, I would assume you would not want PartialEq derived for the BinaryReader as well?

[alexcrichton]

Ideally two different readers would be semantically compared, so you'd for example use .targets() and equate the two. That being said it'd have to deal with errors and is kinda mess. In lieu of that I'd recommend equating .remaining_bytes() or basically the slice contents of the reader

[thesuhas]

I've done that! Used remaining_buffer() to compare the slices of the contents of the reader. Would this work?

[alexcrichton]

Looks good to me, thanks!

[thesuhas]

Could this be made into a release so that I can use it?

[alexcrichton]

Wanted to comment that I haven't forgotten this, I just wanted to sort out a few other things before a release. There's no easy way to make patch releases at this time so this involves major version bumps which requires a bit more coordination.

[alexcrichton]

Ok I've turned the crank over at #1663