93 lines
2.6 KiB
Rust
93 lines
2.6 KiB
Rust
#![allow(clippy::non_ascii_literal)]
|
|
|
|
use proc_macro2::{Delimiter, Group, Punct, Spacing, TokenStream, TokenTree};
|
|
use syn::parse::discouraged::Speculative as _;
|
|
use syn::parse::{Parse, ParseStream, Parser, Result};
|
|
use syn::{parenthesized, Token};
|
|
|
|
#[test]
|
|
#[should_panic(expected = "Fork was not derived from the advancing parse stream")]
|
|
fn smuggled_speculative_cursor_between_sources() {
|
|
struct BreakRules;
|
|
impl Parse for BreakRules {
|
|
fn parse(input1: ParseStream) -> Result<Self> {
|
|
let nested = |input2: ParseStream| {
|
|
input1.advance_to(input2);
|
|
Ok(Self)
|
|
};
|
|
nested.parse_str("")
|
|
}
|
|
}
|
|
|
|
syn::parse_str::<BreakRules>("").unwrap();
|
|
}
|
|
|
|
#[test]
|
|
#[should_panic(expected = "Fork was not derived from the advancing parse stream")]
|
|
fn smuggled_speculative_cursor_between_brackets() {
|
|
struct BreakRules;
|
|
impl Parse for BreakRules {
|
|
fn parse(input: ParseStream) -> Result<Self> {
|
|
let a;
|
|
let b;
|
|
parenthesized!(a in input);
|
|
parenthesized!(b in input);
|
|
a.advance_to(&b);
|
|
Ok(Self)
|
|
}
|
|
}
|
|
|
|
syn::parse_str::<BreakRules>("()()").unwrap();
|
|
}
|
|
|
|
#[test]
|
|
#[should_panic(expected = "Fork was not derived from the advancing parse stream")]
|
|
fn smuggled_speculative_cursor_into_brackets() {
|
|
struct BreakRules;
|
|
impl Parse for BreakRules {
|
|
fn parse(input: ParseStream) -> Result<Self> {
|
|
let a;
|
|
parenthesized!(a in input);
|
|
input.advance_to(&a);
|
|
Ok(Self)
|
|
}
|
|
}
|
|
|
|
syn::parse_str::<BreakRules>("()").unwrap();
|
|
}
|
|
|
|
#[test]
|
|
fn trailing_empty_none_group() {
|
|
fn parse(input: ParseStream) -> Result<()> {
|
|
input.parse::<Token![+]>()?;
|
|
|
|
let content;
|
|
parenthesized!(content in input);
|
|
content.parse::<Token![+]>()?;
|
|
|
|
Ok(())
|
|
}
|
|
|
|
// `+ ( + <Ø Ø> ) <Ø <Ø Ø> Ø>`
|
|
let tokens = TokenStream::from_iter(vec![
|
|
TokenTree::Punct(Punct::new('+', Spacing::Alone)),
|
|
TokenTree::Group(Group::new(
|
|
Delimiter::Parenthesis,
|
|
TokenStream::from_iter(vec![
|
|
TokenTree::Punct(Punct::new('+', Spacing::Alone)),
|
|
TokenTree::Group(Group::new(Delimiter::None, TokenStream::new())),
|
|
]),
|
|
)),
|
|
TokenTree::Group(Group::new(Delimiter::None, TokenStream::new())),
|
|
TokenTree::Group(Group::new(
|
|
Delimiter::None,
|
|
TokenStream::from_iter(vec![TokenTree::Group(Group::new(
|
|
Delimiter::None,
|
|
TokenStream::new(),
|
|
))]),
|
|
)),
|
|
]);
|
|
|
|
parse.parse2(tokens).unwrap();
|
|
}
|