feat(validator): parsing and typechecking for double validators

crates/aiken-lang/src/ast.rs

@@ -322,6 +322,7 @@ pub struct Validator<T, Expr> {
     pub doc: Option<String>,
     pub end_position: usize,
     pub fun: Function<T, Expr>,
+    pub other_fun: Option<Function<T, Expr>>,
     pub location: Span,
     pub params: Vec<Arg<T>>,
 }

crates/aiken-lang/src/format.rs

@@ -504,10 +504,15 @@ impl<'comments> Formatter<'comments> {
         &mut self,
         params: &'a [UntypedArg],
         fun: &'a UntypedFunction,
+        other_fun: &'a Option<UntypedFunction>,
         end_position: usize,
     ) -> Document<'a> {
         // Fn and args
-        let head = "fn".to_doc().append(wrap_args(
+        let head = "fn"
+            .to_doc()
+            .append(" ")
+            .append(fun.name.to_doc())
+            .append(wrap_args(
                 fun.arguments.iter().map(|e| (self.fn_arg(e), false)),
             ));
 
@@ -528,11 +533,7 @@ impl<'comments> Formatter<'comments> {
         };
 
         // validator name(params)
-        let v_head = "validator"
+        let v_head = "validator".to_doc().append(if !params.is_empty() {
-            .to_doc()
-            .append(" ")
-            .append(fun.name.as_str())
-            .append(if !params.is_empty() {
             wrap_args(params.iter().map(|e| (self.fn_arg(e), false)))
         } else {
             "".to_doc()

crates/aiken-lang/src/parser.rs

@@ -242,19 +242,9 @@ pub fn type_alias_parser() -> impl Parser<Token, ast::UntypedDefinition, Error =
 }
 
 pub fn validator_parser() -> impl Parser<Token, ast::UntypedDefinition, Error = ParseError> {
-    just(Token::Validator)
+    let func_parser = just(Token::Fn)
-        .ignore_then(select! {Token::Name {name} => name}.map_with_span(|name, span| (name, span)))
+        .ignore_then(select! {Token::Name {name} => name})
         .then(
-            fn_param_parser()
-                .separated_by(just(Token::Comma))
-                .allow_trailing()
-                .delimited_by(just(Token::LeftParen), just(Token::RightParen))
-                .map_with_span(|arguments, span| (arguments, span))
-                .or_not(),
-        )
-        .then(
-            just(Token::Fn)
-                .ignore_then(
             fn_param_parser()
                 .separated_by(just(Token::Comma))
                 .allow_trailing()
@@ -268,7 +258,7 @@ pub fn validator_parser() -> impl Parser<Token, ast::UntypedDefinition, Error =
                 .delimited_by(just(Token::LeftBrace), just(Token::RightBrace)),
         )
         .map_with_span(
-                    |(((arguments, args_span), return_annotation), body), span| ast::Function {
+            |(((name, (arguments, args_span)), return_annotation), body), span| ast::Function {
                 arguments,
                 body: body.unwrap_or_else(|| expr::UntypedExpr::todo(span, None)),
                 doc: None,
@@ -280,24 +270,49 @@ pub fn validator_parser() -> impl Parser<Token, ast::UntypedDefinition, Error =
                         .unwrap_or_else(|| args_span.end),
                 },
                 end_position: span.end - 1,
-                        name: "".to_string(),
+                name,
                 public: false,
                 return_annotation,
                 return_type: (),
             },
-                )
+        );
-                .delimited_by(just(Token::LeftBrace), just(Token::RightBrace)),
-        )
-        .map_with_span(|((name, opt_extra_params), mut fun), span| {
-            fun.name = name.0;
 
-            let (params, params_span) = opt_extra_params.unwrap_or((vec![], name.1));
+    just(Token::Validator)
+        .ignore_then(
+            fn_param_parser()
+                .separated_by(just(Token::Comma))
+                .allow_trailing()
+                .delimited_by(just(Token::LeftParen), just(Token::RightParen))
+                .map_with_span(|arguments, span| (arguments, span))
+                .or_not(),
+        )
+        .then(
+            func_parser
+                .repeated()
+                .at_least(1)
+                .at_most(2)
+                .delimited_by(just(Token::LeftBrace), just(Token::RightBrace))
+                .map(IntoIterator::into_iter),
+        )
+        .map_with_span(|(opt_extra_params, mut functions), span| {
+            let (params, params_span) = opt_extra_params.unwrap_or((
+                vec![],
+                Span {
+                    start: 0,
+                    // just needs to be the word `validator` at this point
+                    end: span.start + 9,
+                },
+            ));
 
             ast::UntypedDefinition::Validator(ast::Validator {
                 doc: None,
-                fun,
+                // unwrap is safe to do here because
+                // above we use `.at_least(1)`
+                fun: functions.next().unwrap(),
+                other_fun: functions.next(),
                 location: Span {
                     start: span.start,
+                    // capture the span from the optional params
                     end: params_span.end,
                 },
                 params,

crates/aiken-lang/src/tests/check.rs

@@ -53,8 +53,8 @@ fn check_validator(
 #[test]
 fn validator_illegal_return_type() {
     let source_code = r#"
-      validator foo {
+      validator {
-        fn(d, r, c) {
+        fn foo(d, r, c) {
           1
         }
       }
@@ -69,8 +69,8 @@ fn validator_illegal_return_type() {
 #[test]
 fn validator_illegal_arity() {
     let source_code = r#"
-      validator foo {
+      validator {
-        fn(c) {
+        fn foo(c) {
           True
         }
       }
@@ -85,8 +85,8 @@ fn validator_illegal_arity() {
 #[test]
 fn validator_correct_form() {
     let source_code = r#"
-      validator foo {
+      validator {
-        fn(d, r, c) {
+        fn foo(d, r, c) {
           True
         }
       }
@@ -98,8 +98,8 @@ fn validator_correct_form() {
 #[test]
 fn validator_in_lib_warning() {
     let source_code = r#"
-      validator foo {
+      validator {
-        fn(c) {
+        fn foo(c) {
           True
         }
       }

crates/aiken-lang/src/tests/format.rs

@@ -58,16 +58,16 @@ fn test_format_if() {
 #[test]
 fn test_format_validator() {
     let src = indoc! {r#"
-      validator foo ( ) {
+      validator ( ) {
-      fn(d: Datum, r: Redeemer, ctx: ScriptContext) -> Bool {
+      fn foo (d: Datum, r: Redeemer, ctx: ScriptContext) -> Bool {
       True
       }
       }
     "#};
 
     let expected = indoc! {r#"
-      validator foo {
+      validator {
-        fn(d: Datum, r: Redeemer, ctx: ScriptContext) -> Bool {
+        fn foo(d: Datum, r: Redeemer, ctx: ScriptContext) -> Bool {
           True
         }
       }

crates/aiken-lang/src/tests/parser.rs

@@ -41,8 +41,8 @@ fn windows_newline() {
 #[test]
 fn validator() {
     let code = indoc! {r#"
-        validator foo {
+        validator {
-          fn(datum, rdmr, ctx) {
+          fn foo(datum, rdmr, ctx) {
             True
           }
         }
@@ -91,14 +91,120 @@ fn validator() {
                     name: "True".to_string(),
                 },
                 doc: None,
-                location: Span::new((), 18..38),
+                location: Span::new((), 14..38),
                 name: "foo".to_string(),
                 public: false,
                 return_annotation: None,
                 return_type: (),
                 end_position: 52,
             },
-            location: Span::new((), 0..13),
+            other_fun: None,
+            location: Span::new((), 0..9),
+            params: vec![],
+        })],
+    )
+}
+
+#[test]
+fn double_validator() {
+    let code = indoc! {r#"
+        validator {
+          fn foo(datum, rdmr, ctx) {
+            True
+          }
+
+          fn bar(rdmr, ctx) {
+            True
+          }
+        }
+    "#};
+
+    assert_definitions(
+        code,
+        vec![ast::UntypedDefinition::Validator(ast::Validator {
+            doc: None,
+            end_position: 90,
+            fun: Function {
+                arguments: vec![
+                    ast::Arg {
+                        arg_name: ast::ArgName::Named {
+                            name: "datum".to_string(),
+                            label: "datum".to_string(),
+                            location: Span::new((), 21..26),
+                        },
+                        location: Span::new((), 21..26),
+                        annotation: None,
+                        tipo: (),
+                    },
+                    ast::Arg {
+                        arg_name: ast::ArgName::Named {
+                            name: "rdmr".to_string(),
+                            label: "rdmr".to_string(),
+                            location: Span::new((), 28..32),
+                        },
+                        location: Span::new((), 28..32),
+                        annotation: None,
+                        tipo: (),
+                    },
+                    ast::Arg {
+                        arg_name: ast::ArgName::Named {
+                            name: "ctx".to_string(),
+                            label: "ctx".to_string(),
+                            location: Span::new((), 34..37),
+                        },
+                        location: Span::new((), 34..37),
+                        annotation: None,
+                        tipo: (),
+                    },
+                ],
+                body: expr::UntypedExpr::Var {
+                    location: Span::new((), 45..49),
+                    name: "True".to_string(),
+                },
+                doc: None,
+                location: Span::new((), 14..38),
+                name: "foo".to_string(),
+                public: false,
+                return_annotation: None,
+                return_type: (),
+                end_position: 52,
+            },
+            other_fun: Some(Function {
+                arguments: vec![
+                    ast::Arg {
+                        arg_name: ast::ArgName::Named {
+                            name: "rdmr".to_string(),
+                            label: "rdmr".to_string(),
+                            location: Span::new((), 64..68),
+                        },
+                        location: Span::new((), 64..68),
+                        annotation: None,
+                        tipo: (),
+                    },
+                    ast::Arg {
+                        arg_name: ast::ArgName::Named {
+                            name: "ctx".to_string(),
+                            label: "ctx".to_string(),
+                            location: Span::new((), 70..73),
+                        },
+                        location: Span::new((), 70..73),
+                        annotation: None,
+                        tipo: (),
+                    },
+                ],
+                body: expr::UntypedExpr::Var {
+                    location: Span::new((), 81..85),
+                    name: "True".to_string(),
+                },
+                doc: None,
+                location: Span::new((), 57..74),
+                name: "bar".to_string(),
+                public: false,
+                return_annotation: None,
+                return_type: (),
+                end_position: 88,
+            }),
+            location: Span::new((), 0..9),
             params: vec![],
         })],
     )

crates/aiken-lang/src/tipo/infer.rs

@@ -3,8 +3,8 @@ use std::collections::HashMap;
 use crate::{
     ast::{
         DataType, Definition, Function, Layer, ModuleConstant, ModuleKind, RecordConstructor,
-        RecordConstructorArg, Span, Tracing, TypeAlias, TypedDefinition, TypedModule,
+        RecordConstructorArg, Span, Tracing, TypeAlias, TypedDefinition, TypedFunction,
-        UntypedDefinition, UntypedModule, Use, Validator,
+        TypedModule, UntypedDefinition, UntypedModule, Use, Validator,
     },
     builtins,
     builtins::function,
@@ -255,11 +255,12 @@ fn infer_definition(
             location,
             end_position,
             mut fun,
-            mut params,
+            other_fun,
+            params,
         }) => {
             let params_length = params.len();
-            params.append(&mut fun.arguments);
+            let temp_params = params.iter().cloned().chain(fun.arguments);
-            fun.arguments = params;
+            fun.arguments = temp_params.collect();
 
             if let Definition::Fn(mut typed_fun) = infer_definition(
                 Definition::Fn(fun),
@@ -285,10 +286,51 @@ fn infer_definition(
                     });
                 }
 
+                let typed_other_fun = other_fun
+                    .map(|mut other| -> Result<TypedFunction, Error> {
+                        let params = params.into_iter().chain(other.arguments);
+                        other.arguments = params.collect();
+
+                        if let Definition::Fn(mut other_typed_fun) = infer_definition(
+                            Definition::Fn(other),
+                            module_name,
+                            hydrators,
+                            environment,
+                            tracing,
+                            kind,
+                        )? {
+                            if !other_typed_fun.return_type.is_bool() {
+                                return Err(Error::ValidatorMustReturnBool {
+                                    return_type: other_typed_fun.return_type.clone(),
+                                    location: other_typed_fun.location,
+                                });
+                            }
+
+                            other_typed_fun.arguments.drain(0..params_length);
+
+                            if other_typed_fun.arguments.len() < 2
+                                || other_typed_fun.arguments.len() > 3
+                            {
+                                return Err(Error::IncorrectValidatorArity {
+                                    count: typed_fun.arguments.len() as u32,
+                                    location: typed_fun.location,
+                                });
+                            }
+
+                            Ok(other_typed_fun)
+                        } else {
+                            unreachable!(
+                                "validator definition inferred as something other than a function?"
+                            )
+                        }
+                    })
+                    .transpose();
+
                 Ok(Definition::Validator(Validator {
                     doc,
                     end_position,
                     fun: typed_fun,
+                    other_fun: typed_other_fun?,
                     location,
                     params: typed_params,
                 }))

crates/aiken-project/src/blueprint/validator.rs

@@ -272,8 +272,8 @@ mod test {
     fn mint_basic() {
         assert_validator(
             r#"
-            validator mint {
+            validator {
-              fn(redeemer: Data, ctx: Data) {
+              fn mint(redeemer: Data, ctx: Data) {
                 True
               }
             }
@@ -302,8 +302,8 @@ mod test {
     fn mint_parameterized() {
         assert_validator(
             r#"
-            validator mint(utxo_ref: Int) {
+            validator(utxo_ref: Int) {
-              fn(redeemer: Data, ctx: Data) {
+              fn mint(redeemer: Data, ctx: Data) {
                 True
               }
             }
@@ -373,8 +373,8 @@ mod test {
                 Abort
             }
 
-            validator simplified_hydra {
+            validator {
-              fn(datum: State, redeemer: Input, ctx: Data) {
+              fn simplified_hydra(datum: State, redeemer: Input, ctx: Data) {
                 True
               }
             }
@@ -485,8 +485,8 @@ mod test {
     fn tuples() {
         assert_validator(
             r#"
-            validator tuples {
+            validator {
-              fn(datum: (Int, ByteArray), redeemer: (Int, Int, Int), ctx: Void) {
+              fn tuples(datum: (Int, ByteArray), redeemer: (Int, Int, Int), ctx: Void) {
                 True
               }
             }
@@ -560,8 +560,8 @@ mod test {
                 Infinite
             }
 
-            validator generics {
+            validator {
-              fn(redeemer: Either<ByteArray, Interval<Int>>, ctx: Void) {
+              fn generics(redeemer: Either<ByteArray, Interval<Int>>, ctx: Void) {
                 True
               }
             }
@@ -644,8 +644,8 @@ mod test {
 
             type UUID { UUID }
 
-            validator list_2_tuples_as_map {
+            validator {
-              fn(redeemer: Dict<UUID, Int>, ctx: Void) {
+              fn list_2_tuples_as_map(redeemer: Dict<UUID, Int>, ctx: Void) {
                 True
               }
             }
@@ -707,8 +707,8 @@ mod test {
 
             type UUID { UUID }
 
-            validator opaque_singleton_variants {
+            validator {
-              fn(redeemer: Dict<UUID, Int>, ctx: Void) {
+              fn opaque_singleton_variants(redeemer: Dict<UUID, Int>, ctx: Void) {
                 True
               }
             }
@@ -753,8 +753,8 @@ mod test {
                 foo: Data
             }
 
-            validator nested_data {
+            validator {
-              fn(datum: Foo, redeemer: Int, ctx: Void) {
+              fn nested_data(datum: Foo, redeemer: Int, ctx: Void) {
                 True
               }
             }
@@ -814,8 +814,8 @@ mod test {
               Mul(Expr, Expr)
             }
 
-            validator recursive_types {
+            validator {
-              fn(redeemer: Expr, ctx: Void) {
+              fn recursive_types(redeemer: Expr, ctx: Void) {
                 True
               }
             }
@@ -899,8 +899,8 @@ mod test {
                 }
             }
 
-            validator recursive_generic_types {
+            validator {
-              fn(datum: Foo, redeemer: LinkedList<Int>, ctx: Void) {
+              fn recursive_generic_types(datum: Foo, redeemer: LinkedList<Int>, ctx: Void) {
                 True
               }
             }