The following cases do not roundtrip:

• untagged struct variant with PrettyConfig::default().struct_names(true), since
  • serde serializes an untagged struct variant as a struct (ok)
  • the struct is given the name of the enum, which we dutifully serialize (oh no), see https://github.com/serde-rs/serde/blob/ddc1ee564b33aa584e5a66817aafb27c3265b212/serde_derive/src/ser.rs#L960-L964
  • the untagged enum deserializer does NOT allow any idents, since these are interpreted as variant names, which we interpret as enums, while serde is looking for a struct (dang)
  • I have no idea how to solve this, @clouds56 do you have any ideas?
• raw value inside an untagged enum
  • raw values are serialized without any indication that they exist, as is their purpose
  • untagged enums deserialize into serde's content type, which will parse the raw value's content as normal RON
  • the raw value cannot be deserialized from deserialized ron
  • e.g. "\"hi\"" is the raw value "\"hi\"" but the serde content "hi"
  • this could only be solved with a custom content type, which is blocked Internal buffering disrupts format-specific deserialization features serde-rs/serde#1183