The custom one was functionally identical to the default implementation given by
the Deserialize trait. If someone has benchmarks that the custom one performs
better, we can put it back.
When a field should be skipped during deserialization, it will not use its own Default implementation
when the container structure has `#[serde(default)]` set.
There are at least two reasonable things to expect the len field to
check: the length of the fields array passed to deserialize_struct, or
the number of field tokens. Even beyond these, in some cases it can be
useful to test deserialization with a bogus len to test how the
Deserialize impl reacts to an incorrect size_hint.
This reverts commit 436cafb0a3 which was
released in serde_test 1.0.20.
Serde's `ContentDeserializer` and `ContentRefDeserializer`
cannot deserialize struct enum variant associated data when
that data is encoded as a sequence. This failure leads to
errors when decoding an enum nested in another untagged
enum. For example:
#[derive(Serialize, Deserialize)]
#[serde(untagged)]
enum Foo {
A(Bar),
}
#[derive(Serialize, Deserialize)]
enum Bar {
B{f1: String},
}
let data1 = Foo::A(Bar::B{f1: "Hello".into()});
let bytes = rmp_serde::to_vec(&data1).unwrap();
let data2 = rmp_serde::from_slice::<Foo>(&bytes).unwrap();
Deserializing fails with the error `Syntax("data did not
match any variant of untagged enum Foo")`, but the
underlying failure occurs when decoding the associated data
of `Bar::B`.
This pull request fixes the issue by allowing
`ContentDeserializer` and `ContentRefDeserializer` to
deserialize sequence-encoded struct enum variant data.
Before
```
expected Token::Str but serialized as Str(“F9168C5E-CEB2-4FAA-B6BF-329BF39FA1E4")
```
After
```
expected Token::Str(“f9168c5e-ceb2-4faa-b6bf-329bf39fa1e4”) but serialized as Str(“F9168C5E-CEB2-4FAA-B6BF-329BF39FA1E4")
```
David Tolnay