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#![allow(clippy::uninlined_format_args)]
#[macro_use]
mod macros;
use proc_macro2::{Delimiter, Group, TokenStream, TokenTree};
use quote::{quote, ToTokens as _};
use syn::parse::Parser;
use syn::punctuated::Punctuated;
use syn::{parse_quote, token, Item, Pat, PatTuple, Stmt, Token};
#[test]
fn test_pat_ident() {
match Pat::parse_single.parse2(quote!(self)).unwrap() {
Pat::Ident(_) => (),
value => panic!("expected PatIdent, got {:?}", value),
}
}
#[test]
fn test_pat_path() {
match Pat::parse_single.parse2(quote!(self::CONST)).unwrap() {
Pat::Path(_) => (),
value => panic!("expected PatPath, got {:?}", value),
}
}
#[test]
fn test_leading_vert() {
syn::parse_str::<Item>("fn f() {}").unwrap();
syn::parse_str::<Item>("fn fun1(| A: E) {}").unwrap_err();
syn::parse_str::<Item>("fn fun2(|| A: E) {}").unwrap_err();
syn::parse_str::<Stmt>("let | () = ();").unwrap_err();
syn::parse_str::<Stmt>("let (| A): E;").unwrap();
syn::parse_str::<Stmt>("let (|| A): (E);").unwrap_err();
syn::parse_str::<Stmt>("let (| A,): (E,);").unwrap();
syn::parse_str::<Stmt>("let [| A]: [E; 1];").unwrap();
syn::parse_str::<Stmt>("let [|| A]: [E; 1];").unwrap_err();
syn::parse_str::<Stmt>("let TS(| A): TS;").unwrap();
syn::parse_str::<Stmt>("let TS(|| A): TS;").unwrap_err();
syn::parse_str::<Stmt>("let NS { f: | A }: NS;").unwrap();
syn::parse_str::<Stmt>("let NS { f: || A }: NS;").unwrap_err();
}
#[test]
fn test_group() {
let group = Group::new(Delimiter::None, quote!(Some(_)));
let tokens = TokenStream::from_iter(vec![TokenTree::Group(group)]);
let pat = Pat::parse_single.parse2(tokens).unwrap();
snapshot!(pat, @r###"
Pat::TupleStruct {
path: Path {
segments: [
PathSegment {
ident: "Some",
},
],
},
elems: [
Pat::Wild,
],
}
"###);
}
#[test]
fn test_ranges() {
Pat::parse_single.parse_str("..").unwrap();
Pat::parse_single.parse_str("..hi").unwrap();
Pat::parse_single.parse_str("lo..").unwrap();
Pat::parse_single.parse_str("lo..hi").unwrap();
Pat::parse_single.parse_str("..=").unwrap_err();
Pat::parse_single.parse_str("..=hi").unwrap();
Pat::parse_single.parse_str("lo..=").unwrap_err();
Pat::parse_single.parse_str("lo..=hi").unwrap();
Pat::parse_single.parse_str("...").unwrap_err();
Pat::parse_single.parse_str("...hi").unwrap_err();
Pat::parse_single.parse_str("lo...").unwrap_err();
Pat::parse_single.parse_str("lo...hi").unwrap();
Pat::parse_single.parse_str("[lo..]").unwrap_err();
Pat::parse_single.parse_str("[..=hi]").unwrap_err();
Pat::parse_single.parse_str("[(lo..)]").unwrap();
Pat::parse_single.parse_str("[(..=hi)]").unwrap();
Pat::parse_single.parse_str("[lo..=hi]").unwrap();
Pat::parse_single.parse_str("[_, lo.., _]").unwrap_err();
Pat::parse_single.parse_str("[_, ..=hi, _]").unwrap_err();
Pat::parse_single.parse_str("[_, (lo..), _]").unwrap();
Pat::parse_single.parse_str("[_, (..=hi), _]").unwrap();
Pat::parse_single.parse_str("[_, lo..=hi, _]").unwrap();
}
#[test]
fn test_tuple_comma() {
let mut expr = PatTuple {
attrs: Vec::new(),
paren_token: token::Paren::default(),
elems: Punctuated::new(),
};
snapshot!(expr.to_token_stream() as Pat, @"Pat::Tuple");
expr.elems.push_value(parse_quote!(_));
// Must not parse to Pat::Paren
snapshot!(expr.to_token_stream() as Pat, @r###"
Pat::Tuple {
elems: [
Pat::Wild,
Token![,],
],
}
"###);
expr.elems.push_punct(<Token![,]>::default());
snapshot!(expr.to_token_stream() as Pat, @r###"
Pat::Tuple {
elems: [
Pat::Wild,
Token![,],
],
}
"###);
expr.elems.push_value(parse_quote!(_));
snapshot!(expr.to_token_stream() as Pat, @r###"
Pat::Tuple {
elems: [
Pat::Wild,
Token![,],
Pat::Wild,
],
}
"###);
expr.elems.push_punct(<Token![,]>::default());
snapshot!(expr.to_token_stream() as Pat, @r###"
Pat::Tuple {
elems: [
Pat::Wild,
Token![,],
Pat::Wild,
Token![,],
],
}
"###);
}