47 lines
1.5 KiB
Rust

use std::num::NonZeroU8;
use proc_macro2::TokenStream;
use quote::{format_ident, quote, ToTokens};
use syn::{parse::Parse, Error, LitFloat};
#[derive(Clone)]
pub struct MatrixVersionLiteral {
pub(crate) major: NonZeroU8,
pub(crate) minor: u8,
}
impl Parse for MatrixVersionLiteral {
fn parse(input: syn::parse::ParseStream<'_>) -> syn::Result<Self> {
let fl: LitFloat = input.parse()?;
if !fl.suffix().is_empty() {
return Err(Error::new_spanned(
fl,
"matrix version has to be only two positive numbers separated by a `.`",
));
}
let ver_vec: Vec<String> = fl.to_string().split('.').map(&str::to_owned).collect();
let ver: [String; 2] = ver_vec.try_into().map_err(|_| {
Error::new_spanned(&fl, "did not contain only both an X and Y value like X.Y")
})?;
let major: NonZeroU8 = ver[0].parse().map_err(|e| {
Error::new_spanned(&fl, format!("major number failed to parse as >0 number: {e}"))
})?;
let minor: u8 = ver[1]
.parse()
.map_err(|e| Error::new_spanned(&fl, format!("minor number failed to parse: {e}")))?;
Ok(Self { major, minor })
}
}
impl ToTokens for MatrixVersionLiteral {
fn to_tokens(&self, tokens: &mut TokenStream) {
let variant = format_ident!("V{}_{}", u8::from(self.major), self.minor);
tokens.extend(quote! { ::ruma_common::api::MatrixVersion::#variant });
}
}