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#[macro_use]
mod macros;
use proc_macro2::{Delimiter, Group, Literal, Punct, Spacing, TokenStream, TokenTree};
use std::iter::FromIterator;
use syn::Expr;
#[test]
fn test_grouping() {
let tokens: TokenStream = TokenStream::from_iter(vec![
TokenTree::Literal(Literal::i32_suffixed(1)),
TokenTree::Punct(Punct::new('+', Spacing::Alone)),
TokenTree::Group(Group::new(
Delimiter::None,
TokenStream::from_iter(vec![
TokenTree::Literal(Literal::i32_suffixed(2)),
TokenTree::Punct(Punct::new('+', Spacing::Alone)),
TokenTree::Literal(Literal::i32_suffixed(3)),
]),
)),
TokenTree::Punct(Punct::new('*', Spacing::Alone)),
TokenTree::Literal(Literal::i32_suffixed(4)),
]);
assert_eq!(tokens.to_string(), "1i32 + 2i32 + 3i32 * 4i32");
snapshot!(tokens as Expr, @r###"
Expr::Binary {
left: Expr::Lit {
lit: 1i32,
},
op: Add,
right: Expr::Binary {
left: Expr::Group {
expr: Expr::Binary {
left: Expr::Lit {
lit: 2i32,
},
op: Add,
right: Expr::Lit {
lit: 3i32,
},
},
},
op: Mul,
right: Expr::Lit {
lit: 4i32,
},
},
}
"###);
}
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