Derive Macro racros::AutoStr

#[derive(AutoStr)]
{
    // Attributes available to this derive:
    #[str]
    #[autorule]
}

Automatically add TryFrom String and ToString trait to the attached enum.

Usage:

• str: add #[str("str1")] to field will add the conversion from literal “str1” to that field
• Support using multiple str: #str("str")].
• #[autorule = "..." ], support autorules:
  • lowercase.
  • UPPERCASE.
  • camelCase.
  • PascalCase.
  • snake_case.
  • SCREAMING_CASE.

Example:

use racros::AutoStr;

#[derive(AutoStr, Debug)]
enum MyEnum {
    #[str("e1", "E1")]
    E1,
    #[str("e2")]
    E2,
    #[str("e3", "ee")]
    E3,
}

#[derive(AutoStr, Debug)]
enum MyEnum2 {
    E21,
    #[str("e1", "e2")]
    E22(MyEnum),
}

#[derive(AutoStr, Debug)]
#[autorule = "lowercase"]
enum MyEnum3 {
    #[str("E31")]
    E31,
    E32TesT,
    #[str("e2")]
    E33Test(MyEnum2),
}

#[derive(AutoStr, Debug)]
enum MyEnum4 {
    E41(MyEnum),
    E42(MyEnum2),
}

assert!(matches!(MyEnum::try_from("e1"), Ok(MyEnum::E1)));
assert!(matches!(MyEnum::try_from("E1"), Ok(MyEnum::E1)));
assert!(matches!(MyEnum::try_from("e2"), Ok(MyEnum::E2)));
assert!(matches!(MyEnum::try_from("ee"), Ok(MyEnum::E3)));
assert!(matches!(MyEnum::try_from("e4"), Err(_)));

assert!(matches!(MyEnum2::try_from("E21"), Ok(MyEnum2::E21)));
assert!(matches!(
    MyEnum2::try_from("e1"),
    Ok(MyEnum2::E22(MyEnum::E1))
));
assert!(matches!(
    MyEnum2::try_from("e2"),
    Ok(MyEnum2::E22(MyEnum::E2))
));

assert!(matches!(MyEnum3::try_from("E31"), Ok(MyEnum3::E31)));
assert!(matches!(MyEnum3::try_from("e32test"), Ok(MyEnum3::E32TesT)));
assert!(matches!(
    MyEnum3::try_from("e2"),
    Ok(MyEnum3::E33Test(MyEnum2::E22(MyEnum::E2)))
));

assert_eq!(MyEnum::E1.to_string(), "e1");
assert_eq!(MyEnum2::E21.to_string(), "E21");
assert_eq!(MyEnum2::E22(MyEnum::E1).to_string(), "e1");
assert_eq!(MyEnum3::E31.to_string(), "E31");
assert_eq!(MyEnum3::E32TesT.to_string(), "e32test");
assert_eq!(MyEnum3::E33Test(MyEnum2::E22(MyEnum::E3)).to_string(), "e3");
assert!(matches!(
    MyEnum4::try_from("E1"),
    Ok(MyEnum4::E41(MyEnum::E1))
));

assert_eq!(
    MyEnum4::try_from("e1").unwrap_err(),
    "#[str(...)] attribute not set and fallback guess is ambiguous: both MyEnum and MyEnum2 can accept this convert from \"e1\""
);

assert_eq!(
    MyEnum4::try_from("e11").unwrap_err(),
    "failed to convert to MyEnum4 :invalid value \"e11\""
);