| #[macro_use] |
| mod macros; |
| |
| use proc_macro2::{Delimiter, Group, Ident, Punct, Spacing, Span, TokenStream, TokenTree}; |
| use quote::{quote, ToTokens}; |
| use std::iter::FromIterator; |
| use syn::{parse_quote, Expr, Type, TypePath}; |
| |
| #[test] |
| fn parse_interpolated_leading_component() { |
| // mimics the token stream corresponding to `$mod::rest` |
| let tokens = TokenStream::from_iter(vec![ |
| TokenTree::Group(Group::new(Delimiter::None, quote! { first })), |
| TokenTree::Punct(Punct::new(':', Spacing::Joint)), |
| TokenTree::Punct(Punct::new(':', Spacing::Alone)), |
| TokenTree::Ident(Ident::new("rest", Span::call_site())), |
| ]); |
| |
| snapshot!(tokens.clone() as Expr, @r###" |
| Expr::Path { |
| path: Path { |
| segments: [ |
| PathSegment { |
| ident: "first", |
| arguments: None, |
| }, |
| PathSegment { |
| ident: "rest", |
| arguments: None, |
| }, |
| ], |
| }, |
| } |
| "###); |
| |
| snapshot!(tokens as Type, @r###" |
| Type::Path { |
| path: Path { |
| segments: [ |
| PathSegment { |
| ident: "first", |
| arguments: None, |
| }, |
| PathSegment { |
| ident: "rest", |
| arguments: None, |
| }, |
| ], |
| }, |
| } |
| "###); |
| } |
| |
| #[test] |
| fn print_incomplete_qpath() { |
| // qpath with `as` token |
| let mut ty: TypePath = parse_quote!(<Self as A>::Q); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`< Self as A > :: Q`) |
| "###); |
| assert!(ty.path.segments.pop().is_some()); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`< Self as A > ::`) |
| "###); |
| assert!(ty.path.segments.pop().is_some()); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`< Self >`) |
| "###); |
| assert!(ty.path.segments.pop().is_none()); |
| |
| // qpath without `as` token |
| let mut ty: TypePath = parse_quote!(<Self>::A::B); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`< Self > :: A :: B`) |
| "###); |
| assert!(ty.path.segments.pop().is_some()); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`< Self > :: A ::`) |
| "###); |
| assert!(ty.path.segments.pop().is_some()); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`< Self > ::`) |
| "###); |
| assert!(ty.path.segments.pop().is_none()); |
| |
| // normal path |
| let mut ty: TypePath = parse_quote!(Self::A::B); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`Self :: A :: B`) |
| "###); |
| assert!(ty.path.segments.pop().is_some()); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`Self :: A ::`) |
| "###); |
| assert!(ty.path.segments.pop().is_some()); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(`Self ::`) |
| "###); |
| assert!(ty.path.segments.pop().is_some()); |
| snapshot!(ty.to_token_stream(), @r###" |
| TokenStream(``) |
| "###); |
| assert!(ty.path.segments.pop().is_none()); |
| } |