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use quote::ToTokens;
use std::cell::RefCell;
use std::fmt::Display;
use std::thread;
use syn;
#[derive(Default)]
pub struct Ctxt {
errors: RefCell<Option<Vec<syn::Error>>>,
}
impl Ctxt {
pub fn new() -> Self {
Ctxt {
errors: RefCell::new(Some(Vec::new())),
}
}
pub fn error_spanned_by<A: ToTokens, T: Display>(&self, obj: A, msg: T) {
self.errors
.borrow_mut()
.as_mut()
.unwrap()
.push(syn::Error::new_spanned(obj.into_token_stream(), msg));
}
pub fn syn_error(&self, err: syn::Error) {
self.errors.borrow_mut().as_mut().unwrap().push(err);
}
pub fn check(self) -> Result<(), Vec<syn::Error>> {
let errors = self.errors.borrow_mut().take().unwrap();
match errors.len() {
0 => Ok(()),
_ => Err(errors),
}
}
}
impl Drop for Ctxt {
fn drop(&mut self) {
if !thread::panicking() && self.errors.borrow().is_some() {
panic!("forgot to check for errors");
}
}
}