rust/tests/ui/proc-macro/auxiliary/modify-ast.rs

48 lines
1.4 KiB
Rust

//@ force-host
//@ no-prefer-dynamic
#![crate_type = "proc-macro"]
extern crate proc_macro;
use proc_macro::*;
#[proc_macro_attribute]
pub fn assert1(_a: TokenStream, b: TokenStream) -> TokenStream {
assert_eq(b.clone(), "pub fn foo() {}".parse().unwrap());
b
}
#[proc_macro_derive(Foo, attributes(foo))]
pub fn assert2(a: TokenStream) -> TokenStream {
assert_eq(a, "pub struct MyStructc { _a: i32, }".parse().unwrap());
TokenStream::new()
}
fn assert_eq(a: TokenStream, b: TokenStream) {
let mut a = a.into_iter();
let mut b = b.into_iter();
for (a, b) in a.by_ref().zip(&mut b) {
match (a, b) {
(TokenTree::Group(a), TokenTree::Group(b)) => {
assert_eq!(a.delimiter(), b.delimiter());
assert_eq(a.stream(), b.stream());
}
(TokenTree::Punct(a), TokenTree::Punct(b)) => {
assert_eq!(a.as_char(), b.as_char());
assert_eq!(a.spacing(), b.spacing());
}
(TokenTree::Literal(a), TokenTree::Literal(b)) => {
assert_eq!(a.to_string(), b.to_string());
}
(TokenTree::Ident(a), TokenTree::Ident(b)) => {
assert_eq!(a.to_string(), b.to_string());
}
(a, b) => panic!("{:?} != {:?}", a, b),
}
}
assert!(a.next().is_none());
assert!(b.next().is_none());
}