holy 0.2.1

Holy is a proc-macro library that provides helper macros.
Documentation 
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use proc_macro::TokenStream;
use quote::quote;
use syn::{Data, DeriveInput, Field, Fields};

use crate::utils::{determine_visibility, should_skip};

pub fn impl_getters_macro(ast: &DeriveInput) -> Result<TokenStream, syn::Error> {
    let name = &ast.ident;
    let (impl_generics, ty_generics, where_clause) = ast.generics.split_for_impl();

    let getters = match &ast.data {
        Data::Struct(data) => match &data.fields {
            Fields::Named(fields) => fields
                .named
                .iter()
                .filter(|f| !should_skip(&f.attrs))
                .map(generate_getter)
                .collect::<Result<Vec<_>, syn::Error>>()?,
            _ => {
                return Err(syn::Error::new_spanned(
                    ast,
                    "Getters macro only supports structs with named fields",
                ));
            }
        },
        _ => {
            return Err(syn::Error::new_spanned(
                ast,
                "Getters macro only supports structs",
            ));
        }
    };

    let expanded = quote! {
        impl #impl_generics #name #ty_generics #where_clause {
            #(#getters)*
        }
    };

    Ok(TokenStream::from(expanded))
}

fn generate_getter(field: &Field) -> Result<proc_macro2::TokenStream, syn::Error> {
    let field_name = &field.ident;
    let field_type = &field.ty;
    let vis = &field.vis;
    let getter_vis = determine_visibility(vis, &field.attrs)?;

    let getter = quote! {
        #getter_vis fn #field_name(&self) -> &#field_type {
            &self.#field_name
        }
    };

    Ok(getter)
}