allow use of types as namespaces for constructing values.

Signed-off-by: KtorZ <matthias.benkort@gmail.com>

crates/aiken-lang/src/parser/chain/field_access.rs

@@ -1,7 +1,6 @@
 use super::Chain;
 use crate::{
     ast::well_known,
-    expr::UntypedExpr,
     parser::{token::Token, ParseError},
 };
 use chumsky::prelude::*;
@@ -11,25 +10,11 @@ pub(crate) fn parser() -> impl Parser<Token, Chain, Error = ParseError> {
         .ignore_then(choice((
             select! { Token::Else => well_known::VALIDATOR_ELSE.to_string() },
             select! { Token::Name { name } => name, },
+            select! { Token::UpName { name } => name, },
         )))
         .map_with_span(Chain::FieldAccess)
 }
 
-pub(crate) fn constructor() -> impl Parser<Token, UntypedExpr, Error = ParseError> {
-    select! {Token::Name { name } => name}
-        .map_with_span(|module, span| (module, span))
-        .then_ignore(just(Token::Dot))
-        .then(select! {Token::UpName { name } => name})
-        .map_with_span(|((module, m_span), name), span| UntypedExpr::FieldAccess {
-            location: span,
-            label: name,
-            container: Box::new(UntypedExpr::Var {
-                location: m_span,
-                name: module,
-            }),
-        })
-}
-
 #[cfg(test)]
 mod tests {
     use crate::assert_expr;

crates/aiken-lang/src/parser/expr/chained.rs

@@ -53,7 +53,6 @@ pub fn chain_start<'a>(
         pair(expression.clone()),
         record_update(expression.clone()),
         record(expression.clone()),
-        field_access::constructor(),
         and_or_chain(expression.clone()),
         var(),
         tuple(expression.clone()),

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

@@ -2279,7 +2279,7 @@ fn use_type_as_namespace_for_patterns() {
     let source_code = r#"
         use thing.{Foo}
 
-        pub fn bar(foo: Foo) {
+        fn bar(foo: Foo) {
           when foo is {
             Foo.A -> True
             Foo.B -> False
@@ -2335,8 +2335,6 @@ fn use_wrong_type_as_namespace_for_patterns_fails() {
           C
           D
         }
-
-
     "#;
 
     let source_code = r#"
@@ -2361,6 +2359,237 @@ fn use_wrong_type_as_namespace_for_patterns_fails() {
     );
 }
 
+#[test]
+fn use_type_as_namespace_for_constructors() {
+    let dependency = r#"
+        pub type Foo {
+          I(Int)
+          B(Bool)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo.{Foo}
+
+        test my_test() {
+          and {
+            Foo.I(42) == foo.I(42),
+            foo.B(True) == Foo.B(True),
+          }
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(matches!(result, Ok(..)), "{result:#?}");
+}
+
+#[test]
+fn use_type_as_nested_namespace_for_constructors() {
+    let dependency = r#"
+        pub type Foo {
+          I(Int)
+          B(Bool)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo
+
+        test my_test() {
+          trace foo.Foo.I(42)
+          Void
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(matches!(result, Ok(..)), "{result:#?}");
+}
+
+#[test]
+fn use_type_as_namespace_unknown_constructor() {
+    let dependency = r#"
+        pub type Foo {
+          I(Int)
+          B(Bool)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo.{Foo}
+
+        test my_test() {
+          Foo.A == Foo.I(42)
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(
+        matches!(
+            &result,
+            Err((warnings, Error::UnknownTypeConstructor { name, .. })) if name == "A" && warnings.is_empty(),
+        ),
+        "{result:#?}"
+    );
+}
+
+#[test]
+fn use_wrong_type_as_namespace() {
+    let dependency = r#"
+        pub type Foo {
+          I(Int)
+          B(Bool)
+        }
+
+        pub type Bar {
+          S(String)
+          L(List<Int>)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo.{Foo}
+
+        test my_test() {
+          trace Foo.S(@"wut")
+          Void
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(
+        matches!(
+            &result,
+            Err((warnings, Error::UnknownTypeConstructor { name, .. })) if name == "S" && warnings.is_empty(),
+        ),
+        "{result:#?}"
+    );
+}
+
+#[test]
+fn use_wrong_nested_type_as_namespace() {
+    let dependency = r#"
+        pub type Foo {
+          I(Int)
+          B(Bool)
+        }
+
+        pub type Bar {
+          S(String)
+          L(List<Int>)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo
+
+        test my_test() {
+          trace foo.Foo.S(@"wut")
+          Void
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(
+        matches!(
+            &result,
+            Err((warnings, Error::UnknownTypeConstructor { name, .. })) if name == "S" && warnings.is_empty(),
+        ),
+        "{result:#?}"
+    );
+}
+
+#[test]
+fn use_private_type_as_nested_namespace_fails() {
+    let dependency = r#"
+        type Foo {
+          I(Int)
+          B(Bool)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo
+
+        test my_test() {
+          trace foo.Foo.I(42)
+          Void
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(
+        matches!(
+            &result,
+            Err((warnings, Error::UnknownModuleType { name, .. })) if name == "Foo" && warnings.is_empty(),
+        ),
+        "{result:#?}"
+    );
+}
+
+#[test]
+fn use_opaque_type_as_namespace_for_constructors_fails() {
+    let dependency = r#"
+        pub opaque type Foo {
+          I(Int)
+          B(Bool)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo.{Foo}
+
+        test my_test() {
+          trace Foo.I(42)
+          Void
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(
+        matches!(
+            &result,
+            Err((warnings, Error::UnknownTypeConstructor { name, .. })) if name == "I" && warnings.is_empty(),
+        ),
+        "{result:#?}"
+    );
+}
+
+#[test]
+fn use_opaque_type_as_nested_namespace_for_constructors_fails() {
+    let dependency = r#"
+        pub opaque type Foo {
+          I(Int)
+          B(Bool)
+        }
+    "#;
+
+    let source_code = r#"
+        use foo
+
+        test my_test() {
+          trace foo.Foo.I(42)
+          Void
+        }
+    "#;
+
+    let result = check_with_deps(parse(source_code), vec![(parse_as(dependency, "foo"))]);
+
+    assert!(
+        matches!(
+            &result,
+            Err((warnings, Error::UnknownTypeConstructor { name, .. })) if name == "I" && warnings.is_empty(),
+        ),
+        "{result:#?}"
+    );
+}
+
 #[test]
 fn forbid_importing_or_using_opaque_constructors() {
     let dependency = r#"

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

@@ -372,6 +372,53 @@ impl<'a> Environment<'a> {
         }
     }
 
+    #[allow(clippy::result_large_err)]
+    pub fn get_fully_qualified_value_constructor(
+        &self,
+        (module_name, module_location): (&str, Span),
+        (type_name, type_location): (&str, Span),
+        (value, value_location): (&str, Span),
+    ) -> Result<&ValueConstructor, Error> {
+        let (_, module) =
+            self.imported_modules
+                .get(module_name)
+                .ok_or_else(|| Error::UnknownModule {
+                    location: module_location,
+                    name: module_name.to_string(),
+                    known_modules: self
+                        .importable_modules
+                        .keys()
+                        .map(|t| t.to_string())
+                        .collect(),
+                })?;
+
+        let constructors =
+            module
+                .types_constructors
+                .get(type_name)
+                .ok_or_else(|| Error::UnknownModuleType {
+                    location: type_location,
+                    name: type_name.to_string(),
+                    module_name: module.name.clone(),
+                    type_constructors: module.types.keys().map(|t| t.to_string()).collect(),
+                })?;
+
+        let unknown_type_constructor = || Error::UnknownTypeConstructor {
+            location: value_location,
+            name: value.to_string(),
+            constructors: constructors.clone(),
+        };
+
+        if !constructors.iter().any(|s| s.as_str() == value) {
+            return Err(unknown_type_constructor());
+        }
+
+        module
+            .values
+            .get(value)
+            .ok_or_else(unknown_type_constructor)
+    }
+
     #[allow(clippy::result_large_err)]
     pub fn get_type_constructor_mut(
         &mut self,
@@ -464,35 +511,13 @@ impl<'a> Environment<'a> {
                     types: self.known_type_names(),
                 })?;
 
-                let (_, module) =
-                    self.imported_modules
-                        .get(&parent_type.module)
-                        .ok_or_else(|| Error::UnknownModule {
-                            name: parent_type.module.to_string(),
-                            known_modules: self
-                                .importable_modules
-                                .keys()
-                                .map(|t| t.to_string())
-                                .collect(),
-                            location,
-                        })?;
-
                 self.unused_modules.remove(&parent_type.module);
 
-                let empty_vec = vec![];
-                let constructors = module.types_constructors.get(t).unwrap_or(&empty_vec);
-
-                let unknown_type_constructor = || Error::UnknownTypeConstructor {
-                    location,
-                    name: name.to_string(),
-                    constructors: constructors.clone(),
-                };
-
-                if !constructors.iter().any(|constructor| constructor == name) {
-                    return Err(unknown_type_constructor());
-                }
-
-                module.values.get(name).ok_or_else(unknown_type_constructor)
+                self.get_fully_qualified_value_constructor(
+                    (parent_type.module.as_str(), location),
+                    (t, location),
+                    (name, location.map(|start, end| (start + t.len() + 1, end))),
+                )
             }
 
             Some(Namespace::Module(m)) => {

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

@@ -1068,6 +1068,41 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
             return shortcircuit;
         }
 
+        // In case where we find an uppercase var name in a record access chain, we treat the type
+        // as a namespace and lookup the next constructor as if it were imported from the module's
+        // the type originally belong to.
+        match container {
+            UntypedExpr::Var {
+                name: ref type_name,
+                location: type_location,
+            } if TypeConstructor::might_be(type_name) => {
+                return self.infer_type_constructor_access(
+                    (type_name, type_location),
+                    (&label, access_location),
+                );
+            }
+
+            UntypedExpr::FieldAccess {
+                location: type_location,
+                label: ref type_name,
+                container: ref type_container,
+            } if TypeConstructor::might_be(type_name) => {
+                if let UntypedExpr::Var {
+                    name: ref module_name,
+                    location: module_location,
+                } = type_container.as_ref()
+                {
+                    return self.infer_inner_type_constructor_access(
+                        (module_name, *module_location),
+                        (type_name, type_location),
+                        (&label, access_location),
+                    );
+                }
+            }
+
+            _ => (),
+        };
+
         // Attempt to infer the container as a record access. If that fails, we may be shadowing the name
         // of an imported module, so attempt to infer the container as a module access.
         // TODO: Remove this cloning
@@ -1075,7 +1110,7 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
             Ok(record_access) => Ok(record_access),
 
             Err(err) => match container {
-                UntypedExpr::Var { name, location } => {
+                UntypedExpr::Var { name, location } if !TypeConstructor::might_be(&name) => {
                     let module_access =
                         self.infer_module_access(&name, label, &location, access_location);
 
@@ -1162,6 +1197,51 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
         })
     }
 
+    #[allow(clippy::result_large_err)]
+    fn infer_type_constructor_access(
+        &mut self,
+        (type_name, type_location): (&str, Span),
+        (label, label_location): (&str, Span),
+    ) -> Result<TypedExpr, Error> {
+        let parent_type = self
+            .environment
+            .module_types
+            .get(type_name)
+            .ok_or_else(|| Error::UnknownType {
+                location: type_location,
+                name: type_name.to_string(),
+                types: self.environment.known_type_names(),
+            })?;
+
+        let module_name = parent_type.module.clone();
+
+        self.infer_inner_type_constructor_access(
+            (module_name.as_str(), type_location),
+            (type_name, type_location),
+            (label, label_location),
+        )
+    }
+
+    #[allow(clippy::result_large_err)]
+    fn infer_inner_type_constructor_access(
+        &mut self,
+        (module_name, module_location): (&str, Span),
+        (type_name, type_location): (&str, Span),
+        (label, label_location): (&str, Span),
+    ) -> Result<TypedExpr, Error> {
+        self.environment.get_fully_qualified_value_constructor(
+            (module_name, module_location),
+            (type_name, type_location),
+            (label, label_location),
+        )?;
+        self.infer_module_access(
+            module_name,
+            label.to_string(),
+            &type_location,
+            label_location,
+        )
+    }
+
     #[allow(clippy::result_large_err)]
     fn infer_record_access(
         &mut self,
@@ -1169,9 +1249,8 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
         label: String,
         location: Span,
     ) -> Result<TypedExpr, Error> {
-        // Infer the type of the (presumed) record
+        // Infer the type of the (presumed) record.
         let record = self.infer(record)?;
-
         self.infer_known_record_access(record, label, location)
     }