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#![allow(clippy::uninlined_format_args)]
#[macro_use]
mod macros;
use proc_macro2::{Delimiter, Group, Ident, Punct, Spacing, Span, TokenStream, TokenTree};
use quote::{quote, ToTokens};
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([
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",
},
Token![::],
PathSegment {
ident: "rest",
},
],
},
}
"###);
snapshot!(tokens as Type, @r###"
Type::Path {
path: Path {
segments: [
PathSegment {
ident: "first",
},
Token![::],
PathSegment {
ident: "rest",
},
],
},
}
"###);
}
#[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());
}
#[test]
fn parse_parenthesized_path_arguments_with_disambiguator() {
#[rustfmt::skip]
let tokens = quote!(dyn FnOnce::() -> !);
snapshot!(tokens as Type, @r###"
Type::TraitObject {
dyn_token: Some,
bounds: [
TypeParamBound::Trait(TraitBound {
path: Path {
segments: [
PathSegment {
ident: "FnOnce",
arguments: PathArguments::Parenthesized {
output: ReturnType::Type(
Type::Never,
),
},
},
],
},
}),
],
}
"###);
}