1#![allow(clippy::from_iter_instead_of_collect)] 2 3use proc_macro2::{Delimiter, Group, Ident, Span, TokenStream, TokenTree}; 4use std::iter; 5 6#[test] 7fn test_fmt_group() { 8 let ident = Ident::new("x", Span::call_site()); 9 let inner = TokenStream::from_iter(iter::once(TokenTree::Ident(ident))); 10 let parens_empty = Group::new(Delimiter::Parenthesis, TokenStream::new()); 11 let parens_nonempty = Group::new(Delimiter::Parenthesis, inner.clone()); 12 let brackets_empty = Group::new(Delimiter::Bracket, TokenStream::new()); 13 let brackets_nonempty = Group::new(Delimiter::Bracket, inner.clone()); 14 let braces_empty = Group::new(Delimiter::Brace, TokenStream::new()); 15 let braces_nonempty = Group::new(Delimiter::Brace, inner.clone()); 16 let none_empty = Group::new(Delimiter::None, TokenStream::new()); 17 let none_nonempty = Group::new(Delimiter::None, inner); 18 19 // Matches libproc_macro. 20 assert_eq!("()", parens_empty.to_string()); 21 assert_eq!("(x)", parens_nonempty.to_string()); 22 assert_eq!("[]", brackets_empty.to_string()); 23 assert_eq!("[x]", brackets_nonempty.to_string()); 24 assert_eq!("{ }", braces_empty.to_string()); 25 assert_eq!("{ x }", braces_nonempty.to_string()); 26 assert_eq!("", none_empty.to_string()); 27 assert_eq!("x", none_nonempty.to_string()); 28} 29