fix(rust): resolve scalar maps and recursion

lib/codegen/fromcto/rust/rustvisitor.js

@@ -729,11 +729,8 @@ class RustVisitor {
      * @private
      */
     visitMapDeclaration(mapDeclaration, parameters) {
-        const mapKeyType = mapDeclaration.getKey().getType();
-        const mapValueType = mapDeclaration.getValue().getType();
-
-        const keyType = this.toRustType(mapKeyType);
-        const valueType = this.toRustType(mapValueType);
+        const keyType = this.toRustMapEntryType(mapDeclaration, mapDeclaration.getKey());
+        const valueType = this.toRustMapEntryType(mapDeclaration, mapDeclaration.getValue());
 
         parameters.fileWriter.writeLine(
             0,
@@ -744,6 +741,25 @@ class RustVisitor {
         return null;
     }
 
+    /**
+     * Resolves the Rust type of a map key or value, unwrapping scalars
+     * to their underlying primitive since scalars are not emitted.
+     * @param {MapDeclaration} mapDeclaration - the owning map declaration
+     * @param {Object} entry - the map key or value type
+     * @return {string} the corresponding type in Rust
+     * @private
+     */
+    toRustMapEntryType(mapDeclaration, entry) {
+        const type = entry.getType();
+        if (!ModelUtil.isPrimitiveType(type)) {
+            const declaration = mapDeclaration.getModelFile().getType(type);
+            if (declaration?.isScalarDeclaration?.()) {
+                return this.toRustType(declaration.getType());
+            }
+        }
+        return this.toRustType(type);
+    }
+
     /**
      * Visitor design pattern
      * @param {RelationshipDeclaration} relationshipDeclaration - the object being visited
@@ -755,6 +771,8 @@ class RustVisitor {
         let type = relationshipDeclaration.type;
         if (relationshipDeclaration.isArray?.()) {
             type = `Vec<${type}>`;
+        } else {
+            type = `Box<${type}>`;
         }
         if (relationshipDeclaration.isOptional?.()) {
             type = `Option<${type}>`;

test/codegen/__snapshots__/codegen.js.snap

@@ -6083,7 +6083,7 @@ pub enum TShirtSizeType {
    LARGE,
 }
 
-pub type EmployeeTShirtSizes = HashMap<SSN, TShirtSizeType>;
+pub type EmployeeTShirtSizes = HashMap<String, TShirtSizeType>;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Address {
@@ -6172,15 +6172,15 @@ pub struct Info {
 
 pub type CompanyProperties = HashMap<String, String>;
 
-pub type EmployeeLoginTimes = HashMap<String, Time>;
+pub type EmployeeLoginTimes = HashMap<String, DateTime<Utc>>;
 
-pub type EmployeeSocialSecurityNumbers = HashMap<String, SSN>;
+pub type EmployeeSocialSecurityNumbers = HashMap<String, String>;
 
-pub type NextOfKin = HashMap<KinName, KinTelephone>;
+pub type NextOfKin = HashMap<String, String>;
 
 pub type EmployeeProfiles = HashMap<String, Concept>;
 
-pub type EmployeeDirectory = HashMap<SSN, Employee>;
+pub type EmployeeDirectory = HashMap<String, Employee>;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Company {
@@ -6402,7 +6402,7 @@ pub struct Employee {
       rename = "manager",
       skip_serializing_if = "Option::is_none",
    )]
-   pub manager: Option<Manager>,
+   pub manager: Option<Box<Manager>>,
 
    #[serde(
       rename = "email",
@@ -6474,7 +6474,7 @@ pub struct Contractor {
       rename = "manager",
       skip_serializing_if = "Option::is_none",
    )]
-   pub manager: Option<Manager>,
+   pub manager: Option<Box<Manager>>,
 
    #[serde(
       rename = "email",
@@ -6582,7 +6582,7 @@ pub struct Manager {
       rename = "manager",
       skip_serializing_if = "Option::is_none",
    )]
-   pub manager: Option<Manager>,
+   pub manager: Option<Box<Manager>>,
 
    #[serde(
       rename = "email",
@@ -6663,7 +6663,7 @@ pub struct Onboarded {
    #[serde(
       rename = "employee",
    )]
-   pub employee: Employee,
+   pub employee: Box<Employee>,
 
    #[serde(
       rename = "$timestamp",
@@ -6683,7 +6683,7 @@ pub struct ChangeOfAddress {
    #[serde(
       rename = "Person",
    )]
-   pub person: Person,
+   pub person: Box<Person>,
 
    #[serde(
       rename = "newAddress",

test/codegen/fromcto/rust/rustvisitor.js

@@ -1191,7 +1191,7 @@ describe('RustVisitor', function () {
                     [1, '#[serde('],
                     [2, 'rename = "Bob",'],
                     [1, ')]'],
-                    [1, 'pub bob: Person,'],
+                    [1, 'pub bob: Box<Person>,'],
                 ]);
         });
 
@@ -1236,7 +1236,7 @@ describe('RustVisitor', function () {
                     [2, 'rename = "Bob",'],
                     [2, 'skip_serializing_if = "Option::is_none",'],
                     [1, ')]'],
-                    [1, 'pub bob: Option<Person>,'],
+                    [1, 'pub bob: Option<Box<Person>>,'],
                 ]);
         });
 
@@ -1775,6 +1775,29 @@ describe('RustVisitor', function () {
             ).calledOnce.should.be.ok;
         });
 
+        it('should unwrap scalar key and value types to their primitives', () => {
+            mockMapDeclaration.getName.returns('DirectoryMap');
+            mockMapDeclaration.getKey.returns(mockMapKey);
+            mockMapDeclaration.getValue.returns(mockMapValue);
+            mockMapKey.getType.returns('SSN');
+            mockMapValue.getType.returns('Employee');
+            mockMapDeclaration.getModelFile.returns(mockModelFile);
+            mockModelFile.getType.withArgs('SSN').returns({
+                isScalarDeclaration: () => true,
+                getType: () => 'String',
+            });
+            mockModelFile.getType.withArgs('Employee').returns({
+                isScalarDeclaration: () => false,
+            });
+
+            rustVisitor.visitMapDeclaration(mockMapDeclaration, param);
+
+            param.fileWriter.writeLine.withArgs(
+                0,
+                'pub type DirectoryMap = HashMap<String, Employee>;'
+            ).calledOnce.should.be.ok;
+        });
+
         it('should handle DateTime key types', () => {
             mockMapDeclaration.getName.returns('EventMap');
             mockMapDeclaration.getKey.returns(mockMapKey);

test/verification/cases.js

@@ -47,7 +47,6 @@ const CASES = [
             // jsonschema: 'empty Level enum produces invalid JSON Schema (enum must have >= 1 item)',
             protobuf:'Empty enum produces invalid Protobuf (enum must have >= 1 item)',
             graphql: 'map types emit invalid GraphQL SDL (key/value field syntax)',
-            rust: 'map declarations reference scalar key/value types (e.g. SSN) that the Rust visitor does not emit, so cargo check fails',
             avro: 'versioned namespaces (e.g. concerto.decorator@1.0.0) are illegal Avro identifiers (segment "0")',
             golang: 'GoLangVisitor emits bare package-name imports (e.g. import "concerto_decorator_1_0_0") instead of Go module-relative import paths, so any cross-namespace model fails go build',
         },
@@ -61,7 +60,6 @@ const CASES = [
             // jsonschema: 'ambiguous $ref for org.acme.hr@1.0.0.Person.nextOfKin',
             protobuf: 'Empty enum produces invalid Protobuf (enum must have >= 1 item) and scalar map keys (e.g. SSN) are not valid Proto3 map key types',
             graphql: 'map types emit invalid GraphQL SDL (key/value field syntax)',
-            rust: 'map declarations reference scalar key/value types (e.g. SSN, Time) that the Rust visitor does not emit, so cargo check fails',
             avro: 'versioned namespaces (e.g. concerto.decorator@1.0.0) are illegal Avro identifiers (segment "0")',
             openapi: 'JSON Schema $decorators and invalid schema nesting fail OpenAPI struct validation',
             golang: 'GoLangVisitor emits bare package-name imports (e.g. import "concerto_decorator_1_0_0") instead of Go module-relative import paths, so any cross-namespace model fails go build',