Unit variant of externally tagged enum cannot be deserialized from the string
token by itself. It is ContentDeserializer + serde_test::Deserializer that makes
this possible, because serde_test::Deserializer produces Content::Str() from
Token::BorrowedStr() and ContentDeserializer produces unit variant from Content::Str().
The following tokens all produces Content::String(variant):
- Token::String(variant)
- Token::Str(variant)
- Token::UnitVariant { variant, .. }
Token::BorrowedStr(variant) produces Content::Str(variant) that was the real purpose to
use it in test in #933. This actually makes this test testing `Content` rather than type itself.
Correct way to represent enum one of:
- [xxxVariant { .. }]
- [Enum { .. }, xxxVariant { variant, .. }]
- [Enum { .. }, String(variant), <variant content>]
- [Enum { .. }, Str(variant), <variant content>]
- [Enum { .. }, BorrowedStr(variant), <variant content>]
84d1c5385d