Update code to use syn 2.0 parser

Cargo.toml

@@ -27,12 +27,12 @@ name = "fibonacci"
 harness = false
 
 [dev-dependencies]
-trybuild = "1.0.56"
+trybuild = "1.0.79"
 criterion = { version = "0.4.0", features = ["html_reports"] }
-fnv = "1.0"
+fnv = "1.0.7"
 
 [dependencies]
-syn = { version = "1.0", features = ["full"] }
+syn = { version = "2.0", features = ["full"] }
 quote = "1.0"
 proc-macro2 = "1.0"
 proc-macro-error = "1.0"

src/lib.rs

@@ -1192,7 +1192,7 @@ fn is_datalog_var(expr: &Expr) -> Option<Ident> {
 /// are bound by that pattern.
 fn pat_datalog_vars(pat: &Pat, datalog_vars: &mut HashSet<String>) {
     match pat {
-        Pat::Box(pb) => pat_datalog_vars(&pb.pat, datalog_vars),
+        Pat::Const(_) => (),
         Pat::Ident(pi) => {
             datalog_vars.insert(pi.ident.to_string());
             if let Some((_, ref p)) = pi.subpat {
@@ -1202,6 +1202,7 @@ fn pat_datalog_vars(pat: &Pat, datalog_vars: &mut HashSet<String>) {
         Pat::Lit(_) => (),
         Pat::Macro(pm) => abort!(pm.span(), "Macros not allowed in let bindings."),
         Pat::Or(_) => (),
+        Pat::Paren(pp) => pat_datalog_vars(&pp.pat, datalog_vars),
         Pat::Path(_) => (),
         Pat::Range(_) => (),
         Pat::Reference(pr) => pat_datalog_vars(&pr.pat, datalog_vars),
@@ -1222,7 +1223,7 @@ fn pat_datalog_vars(pat: &Pat, datalog_vars: &mut HashSet<String>) {
             }
         }
         Pat::TupleStruct(pts) => {
-            for e in &pts.pat.elems {
+            for e in &pts.elems {
                 pat_datalog_vars(e, datalog_vars);
             }
         }

src/parse.rs

@@ -88,7 +88,7 @@ impl Parse for Relation {
             name: input.parse()?,
             generics: input.parse()?,
             paren_token: parenthesized!(content in input),
-            fields: content.parse_terminated(Field::parse_unnamed)?,
+            fields: content.parse_terminated(Field::parse_unnamed, Token![,])?,
             semi_token: input.parse()?,
         })
     }
@@ -173,17 +173,20 @@ impl Parse for Fact {
             negate: input.parse()?,
             relation: input.parse()?,
             paren_token: parenthesized!(content in input),
-            fields: content.parse_terminated(|input| {
-                if input.peek(Token![_]) {
-                    Ok(FactField::Ignored(input.parse()?))
-                } else if input.peek(Token![ref]) {
-                    let ref_tok: Token![ref] = input.parse()?;
-                    let ident: Ident = input.parse()?;
-                    Ok(FactField::Ref(ref_tok, ident))
-                } else {
-                    Ok(FactField::Expr(input.parse()?))
-                }
-            })?,
+            fields: content.parse_terminated(
+                |input| {
+                    if input.peek(Token![_]) {
+                        Ok(FactField::Ignored(input.parse()?))
+                    } else if input.peek(Token![ref]) {
+                        let ref_tok: Token![ref] = input.parse()?;
+                        let ident: Ident = input.parse()?;
+                        Ok(FactField::Ref(ref_tok, ident))
+                    } else {
+                        Ok(FactField::Expr(input.parse()?))
+                    }
+                },
+                Token![,],
+            )?,
         })
     }
 }
@@ -201,7 +204,7 @@ impl Parse for For {
         #[allow(clippy::mixed_read_write_in_expression)]
         Ok(Self {
             for_token: input.parse()?,
-            pat: input.parse()?,
+            pat: Pat::parse_single(input)?,
             in_token: input.parse()?,
             expr: input.parse()?,
         })

tests/ui/bad_goal_input.stderr

@@ -1,5 +1,5 @@
 error: Relations marked as @input cannot be derived from a rule.
-  --> $DIR/bad_goal_input.rs:11:9
+  --> tests/ui/bad_goal_input.rs:11:9
    |
 11 |         In(0, 0);
    |         ^^

tests/ui/bad_visibility_of_relation.stderr

@@ -1,5 +1,5 @@
 error[E0603]: tuple struct constructor `Test` is private
-  --> $DIR/bad_visibility_of_relation.rs:21:22
+  --> tests/ui/bad_visibility_of_relation.rs:21:22
    |
 9  |         struct Test(u32);
    |                     --- a constructor is private if any of the fields is private
@@ -8,13 +8,17 @@ error[E0603]: tuple struct constructor `Test` is private
    |                      ^^^^ private tuple struct constructor
    |
 note: the tuple struct constructor `Test` is defined here
-  --> $DIR/bad_visibility_of_relation.rs:9:9
+  --> tests/ui/bad_visibility_of_relation.rs:9:9
    |
 9  |         struct Test(u32);
    |         ^^^^^^^^^^^^^^^^^
+help: consider making the field publicly accessible
+   |
+9  |         struct Test(pub u32);
+   |                     +++
 
 error[E0603]: tuple struct constructor `MoreTest` is private
-  --> $DIR/bad_visibility_of_relation.rs:22:22
+  --> tests/ui/bad_visibility_of_relation.rs:22:22
    |
 12 |         pub struct MoreTest(bool);
    |                             ---- a constructor is private if any of the fields is private
@@ -23,7 +27,11 @@ error[E0603]: tuple struct constructor `MoreTest` is private
    |                      ^^^^^^^^ private tuple struct constructor
    |
 note: the tuple struct constructor `MoreTest` is defined here
-  --> $DIR/bad_visibility_of_relation.rs:12:9
+  --> tests/ui/bad_visibility_of_relation.rs:12:9
    |
 12 |         pub struct MoreTest(bool);
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^
+help: consider making the field publicly accessible
+   |
+12 |         pub struct MoreTest(pub bool);
+   |                             +++

tests/ui/capital_letter_var.stderr

@@ -1,11 +1,11 @@
 error[E0425]: cannot find value `Not_a_variable` in this scope
- --> $DIR/capital_letter_var.rs:8:30
+ --> tests/ui/capital_letter_var.rs:8:30
   |
 8 |     Ok(Not_a_variable) <- Ok(Not_a_variable);
   |                              ^^^^^^^^^^^^^^ not found in this scope
 
 error[E0425]: cannot find value `Not_a_variable` in this scope
- --> $DIR/capital_letter_var.rs:8:8
+ --> tests/ui/capital_letter_var.rs:8:8
   |
 8 |     Ok(Not_a_variable) <- Ok(Not_a_variable);
   |        ^^^^^^^^^^^^^^ not found in this scope

tests/ui/invalid_arity.stderr

@@ -1,5 +1,5 @@
 error: Relation 'Fib' was declared with arity 2, but constructed with arity 3 here.
-  --> $DIR/invalid_arity.rs:10:9
+  --> tests/ui/invalid_arity.rs:10:9
    |
 10 |         Fib(0, 0, 2);
    |         ^^^

tests/ui/non_input_lifetime.stderr

@@ -1,5 +1,5 @@
 error: Lifetime on output relation without any input relations having a lifetime
-  --> $DIR/non_input_lifetime.rs:14:22
+  --> tests/ui/non_input_lifetime.rs:14:22
    |
 14 |         struct Output<'a>(&'a u32);
    |                      ^^^^

tests/ui/recursive_negation.stderr

@@ -1,5 +1,5 @@
 error: Negation of relation 'Ok' creates a dependency cycle and cannot be stratified.
- --> $DIR/recursive_negation.rs:8:14
+ --> tests/ui/recursive_negation.rs:8:14
   |
 8 |     Ok() <- !Ok();
   |              ^^

tests/ui/unbound_variable.stderr

@@ -1,23 +1,23 @@
 error[E0425]: cannot find value `n` in this scope
-  --> $DIR/unbound_variable.rs:13:30
+  --> tests/ui/unbound_variable.rs:13:30
    |
 13 |         Fib(n, x + y) <- Fib(n - 1, x), Fib(n - 2, y), (n <= 25);
    |                              ^ not found in this scope
 
 error[E0425]: cannot find value `n` in this scope
-  --> $DIR/unbound_variable.rs:13:45
+  --> tests/ui/unbound_variable.rs:13:45
    |
 13 |         Fib(n, x + y) <- Fib(n - 1, x), Fib(n - 2, y), (n <= 25);
    |                                             ^ help: a local variable with a similar name exists: `x`
 
 error[E0425]: cannot find value `n` in this scope
-  --> $DIR/unbound_variable.rs:13:57
+  --> tests/ui/unbound_variable.rs:13:57
    |
 13 |         Fib(n, x + y) <- Fib(n - 1, x), Fib(n - 2, y), (n <= 25);
    |                                                         ^ help: a local variable with a similar name exists: `x`
 
 error[E0425]: cannot find value `n` in this scope
-  --> $DIR/unbound_variable.rs:13:13
+  --> tests/ui/unbound_variable.rs:13:13
    |
 13 |         Fib(n, x + y) <- Fib(n - 1, x), Fib(n - 2, y), (n <= 25);
    |             ^ help: a local variable with a similar name exists: `x`

tests/ui/underscore_in_goal.stderr

@@ -1,5 +1,5 @@
 error: Cannot have _ in goal atom of rule.
- --> $DIR/underscore_in_goal.rs:7:8
+ --> tests/ui/underscore_in_goal.rs:7:8
   |
 7 |     Ok(_) <- Ok(_);
   |        ^