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#![recursion_limit = "1024"]
extern crate proc_macro;
#[macro_use] extern crate quote;
use proc_macro::TokenStream;
use syn::Result;
trait CustomDerive: Sized {
fn parse(input: syn::DeriveInput, tokens: proc_macro2::TokenStream) -> Result<Self>;
fn emit(self) -> Result<proc_macro2::TokenStream>;
}
fn run_custom_derive<T>(input: TokenStream) -> TokenStream
where
T: CustomDerive,
{
let input: proc_macro2::TokenStream = input.into();
let tokens = input.clone();
let token_stream = match syn::parse2(input)
.and_then(|input| <T as CustomDerive>::parse(input, tokens))
.and_then(<T as CustomDerive>::emit)
{
Ok(token_stream) => token_stream,
Err(err) => err.to_compile_error(),
};
token_stream.into()
}
trait ResultExt<T> {
fn spanning(self, spanned: impl quote::ToTokens) -> Result<T>;
}
impl<T, E> ResultExt<T> for std::result::Result<T, E>
where
E: std::fmt::Display,
{
fn spanning(self, spanned: impl quote::ToTokens) -> Result<T> {
self.map_err(|err| syn::Error::new_spanned(spanned, err))
}
}
mod custom_resource;
use custom_resource::CustomResource;
#[proc_macro_derive(CustomResource, attributes(kube))]
pub fn derive_custom_resource(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
run_custom_derive::<CustomResource>(input)
}