Typelevel Cats based module added

[yisraelU]

A module that provides a Schema Visitor for the Show and Hash typeclasses from Typelevel Cats
Implementation as follows
The general direction for Hash, is to provide a hashcode for data based off its its data model vs a smithy4s implementation detail.
This leads to data wrappers that are not reflective of the model , to be excluded from the hash implementation
*Wherever hashes are combined , this is done using the strategies outlined in MurmurHash3

• Structs
  • This follows closely the scala implementation for hashing Products . It combines productSeed, the struct ShapeId name, and the hash of all its parts
• Unions
  • Combination of hash of label and the value
• Enumerations
  • here an Enumeration is treated as its underlying data type , if its an IntEnum as an integer otherwise a String

[yisraelU]

@Baccata
Im thinking should the Hash instance of ByteArray be implemented the way it is

_.array.hashCode

Based upon our discussions above it should be different because its wrapped in a case class

In addition should Enumeration use the case class/object formula or the hash of the underlying values , perhaps string value combined with int value

[Baccata]

Im thinking should the Hash instance of ByteArray be implemented the way it is
Based upon our discussions above it should be different because its wrapped in a case class

In this case the wrapping in a case class is an implementation detail, as opposed to something that's reflected in the metamodel.

When you wrap a piece of data in a structure at the smithy level however, the hashcode driven by the schema (which reflects that smithy-level information) ought to take the wrapping into consideration.

In addition should Enumeration use the case class/object formula or the hash of the underlying values , perhaps string value combined with int value

Good question. For enumeration, I think we should use either the hashcode of the Int value if the enum has the IntEnum hint, or the hashcode of the String value otherwise.