bon-macros 2.3.0

This is a proc-macro crate that is supposed to be a private implementation detail of the `bon` crate
Documentation 
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use crate::builder;
use crate::normalization::{ExpandCfg, ExpansionOutput};
use crate::util::prelude::*;

pub(crate) fn generate(params: TokenStream2, item: TokenStream2) -> TokenStream2 {
    try_generate(params, item.clone())
        .unwrap_or_else(|err| crate::error::error_into_token_stream(err, item))
}

pub(crate) fn try_generate(params: TokenStream2, item: TokenStream2) -> Result<TokenStream2> {
    let item: syn::Item = syn::parse2(item)?;
    let macro_path = syn::parse_quote!(::bon::bon);

    let ctx = ExpandCfg {
        macro_path,
        params,
        item,
    };

    let (_params, item) = match ctx.expand_cfg()? {
        ExpansionOutput::Expanded { params, item } => (params, item),
        ExpansionOutput::Recurse(output) => return Ok(output),
    };

    match item {
        syn::Item::Impl(item_impl) => builder::item_impl::generate(item_impl),
        _ => bail!(
            &item,
            "`#[bon]` attribute is expected to be placed on an `impl` block \
             but it was placed on other syntax instead"
        ),
    }
}