#[serde(try_from)] should error if there are any field-level attributes

[jonhoo]

The following code currently compiles:

use serde_derive::Deserialize;

#[derive(Deserialize)]
#[serde(try_from = "bool")]
struct Foo {
    #[serde(rename = "foo")]
    bar: bool,
}

impl TryFrom<bool> for Foo {
    type Error = std::convert::Infallible;
    fn try_from(bar: bool) -> Result<Self, Self::Error> {
        Ok(Foo { bar })
    }
}

However, I'd argue it should not — serde should probably complain that the #[serde(rename)] will be ignored because of the #[serde(try_from)], as otherwise the user likely made an erroneous assumption.

This may be too breaking a change to do within 1.0, but worth highlighting for the potential future.

[jonhoo]

One compromise might be to emit #[deprecated] attributes to at least get warnings about the ignore attributes.