Mark newtype wrappers as #[serde(transparent)]#724
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hawkw
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This seems like the right thing to do to me!
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In JSON, the difference between a newtype that's transparent or not is unobservable--they both render to the same serialized output. This is not true of other serializations and--more critically--not true of other implementations of
serde::Serializer.In particular, I encountered this in oxidecomputer/progenitor#1017 where I observed that the
serde_urlencoded::Serializerfreaks out about our newtype wrappers. Perhaps this freak out is reasonable because the intended representation matches with the intention oftransparent.Consider the case where I noticed this:
struct Name(String).Namewraps a String and imposes constraints on it. It deserializes from a string and its intended serialization is a string--the newtype wrapper is purely a type for enforcing constraints when creating or manipulating the type. This hasn't bit us before, but marking these newtypes as transparent seems like the right thing to do.