educe 0.7.1

This crate offers procedural macros designed to facilitate the swift implementation of Rust's built-in traits.
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use quote::ToTokens;
use syn::{Expr, Lit, LitStr, Meta, MetaNameValue, Path};

// These helpers parse path parameters such as `method(my_function)` or `method = "my_function"`.
#[inline]
pub(crate) fn meta_name_value_2_path(name_value: &MetaNameValue) -> syn::Result<Path> {
    match &name_value.value {
        Expr::Lit(lit) => {
            if let Lit::Str(lit) = &lit.lit {
                return lit.parse();
            }
        },
        Expr::Path(path) => return Ok(path.path.clone()),
        _ => (),
    }

    Err(syn::Error::new_spanned(
        &name_value.value,
        format!("expected `{path} = Path`", path = path_to_string(&name_value.path)),
    ))
}

#[inline]
pub(crate) fn meta_2_path(meta: &Meta) -> syn::Result<Path> {
    match &meta {
        Meta::NameValue(name_value) => meta_name_value_2_path(name_value),
        Meta::List(list) => {
            if let Ok(lit) = list.parse_args::<LitStr>() {
                lit.parse()
            } else {
                list.parse_args()
            }
        },
        Meta::Path(path) => Err(syn::Error::new_spanned(
            path,
            format!("expected `{path} = Path` or `{path}(Path)`", path = path_to_string(path)),
        )),
    }
}

#[inline]
pub(crate) fn path_to_string(path: &Path) -> String {
    path.into_token_stream().to_string().replace(' ', "")
}