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extern crate proc_macro;
#[cfg(not(feature = "unstable"))]
use proc_macro_hack::proc_macro_hack;
use proc_macro2::TokenStream;
use quote::quote;
use syn::{Lit, LitByteStr, LitStr};
use unindent::*;
#[cfg_attr(feature = "unstable", proc_macro)]
#[cfg_attr(not(feature = "unstable"), proc_macro_hack)]
pub fn indoc(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
let source = TokenStream::from(input);
let len = source.clone().into_iter().count();
if len != 1 {
panic!(
"argument must be a single string literal, but got {} tokens",
len
);
}
let lit = match syn::parse2::<Lit>(source) {
Ok(lit) => lit,
Err(_) => {
panic!("argument must be a single string literal");
}
};
let lit = match lit {
Lit::Str(lit) => {
let v = unindent(&lit.value());
Lit::Str(LitStr::new(&v, lit.span()))
}
Lit::ByteStr(lit) => {
let v = unindent_bytes(&lit.value());
Lit::ByteStr(LitByteStr::new(&v, lit.span()))
}
_ => {
panic!("argument must be a single string literal");
}
};
proc_macro::TokenStream::from(quote!(#lit))
}