feat(from_str): support rename attribute

[tisonkun]

This refers to #216 and #480

Synopsis

This supports:

#[derive(Debug, Eq, FromStr, PartialEq)]
enum Enum {
    #[from_str(rename = "foo")]
    Foo,
    #[from_str(rename = "bar")]
    Bar,
}

Solution

Checklist

• Documentation is updated (if required)
• Tests are added/updated (if required)
• CHANGELOG entry is added (if required)

[tisonkun]

Let me try to fix CI failures.

[tisonkun]

compiler error output diverges between stable and nightly. Not sure what we can do.

[tisonkun]

Weird. I run cargo +stable test --workspace --features full,testing-helpers locally and it doesn't fail:

rustc --version --verbose
rustc 1.92.0 (ded5c06cf 2025-12-08)
binary: rustc
commit-hash: ded5c06cf21d2b93bffd5d884aa6e96934ee4234
commit-date: 2025-12-08
host: aarch64-apple-darwin
release: 1.92.0
LLVM version: 21.1.3

[tisonkun]

cc @JelteF @tyranron