Ref description override component

modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/ModelUtils.java

@@ -1379,6 +1379,14 @@ public static Schema unaliasSchema(OpenAPI openAPI,
                 return schema;
             }
             Schema ref = allSchemas.get(simpleRef);
+
+            // override the description of the referenced component
+            if(ref != null) {
+                if(schema.getDescription() != null) {
+                    ref.setDescription(schema.getDescription());
+                }
+            }
+
             if (ref == null) {
                 if (!isRefToSchemaWithProperties(schema.get$ref())) {
                     once(LOGGER).warn("{} is not defined", schema.get$ref());

modules/openapi-generator/src/test/java/org/openapitools/codegen/typescript/TypeScriptClientCodegenTest.java

@@ -294,4 +294,33 @@ public void testUseErasableSyntaxConfig() throws IOException {
             }
         }
     }
+
+    @Test
+    public void testRefDescription() throws Exception {
+        final File output = Files.createTempDirectory("typescriptnodeclient_").toFile();
+        output.deleteOnExit();
+
+        final CodegenConfigurator configurator = new CodegenConfigurator()
+                .setGeneratorName("typescript")
+                .setInputSpec("src/test/resources/3_0/typescript/ref-description.yaml")
+                .setOutputDir(output.getAbsolutePath().replace("\\", "/"));
+
+        final ClientOptInput clientOptInput = configurator.toClientOptInput();
+        final DefaultGenerator generator = new DefaultGenerator();
+        final List<File> files = generator.opts(clientOptInput).generate();
+        files.forEach(File::deleteOnExit);
+
+        Path file = Paths.get(output + "/models/PetUpdateRequest.ts");
+        // verify ref description is found
+        TestUtils.assertFileContains(
+                file,
+                "Reference description of Date schema"
+        );
+        // verify component description is not present
+        TestUtils.assertFileNotContains(
+                file,
+                "Component description of Date schema"
+        );
+    }
+
 }

modules/openapi-generator/src/test/java/org/openapitools/codegen/utils/ModelUtilsTest.java

@@ -242,6 +242,24 @@ public void testAliasedTypeIsNotUnaliasedIfUsedForImportMapping() {
         Assert.assertEquals(stringSchema, ModelUtils.unaliasSchema(openAPI, emailSchema, new HashMap<>()));
     }
 
+    @Test
+    public void testOverrideAliasedSchemaDescription() {
+        Schema emailSchema = new Schema()
+                .$ref("#/components/schemas/Email")
+                .type("string")
+                .description("description of the reference");
+        StringSchema stringSchema = new StringSchema();
+        stringSchema.setDescription("description of Email component");
+
+        HashMap<String, String> schemaMappings = new HashMap<>();
+        schemaMappings.put("Email", "foo.bar.Email");
+
+        OpenAPI openAPI = TestUtils.createOpenAPIWithOneSchema("Email", stringSchema);
+
+        var unaliasSchema = ModelUtils.unaliasSchema(openAPI, emailSchema, schemaMappings);
+        Assert.assertEquals(unaliasSchema.getDescription(), "description of the reference");
+    }
+
     /**
      * Issue https://github.com/OpenAPITools/openapi-generator/issues/1624.
      * ModelUtils.isFreeFormObject() should not throw an NPE when passed an empty

modules/openapi-generator/src/test/resources/3_0/typescript/ref-description.yaml

@@ -0,0 +1,111 @@
+openapi: 3.1.0
+info:
+  description: test order parameters
+  version: 1.0.0
+  title: Test order parameters
+  license:
+    name: Apache-2.0
+    url: 'https://www.apache.org/licenses/LICENSE-2.0.html'
+
+paths:
+  /pets:
+    get:
+      tags:
+        - default
+      summary: Finds Pets
+      deprecated: true
+      description: Find all pets
+      operationId: findPets
+      parameters:
+        - name: type
+          in: query
+          description: type of pet
+          style: form
+          explode: false
+          schema:
+            type: string
+            default: available
+        - name: name
+          in: query
+          description: name of pet
+          required: true
+          schema:
+            type: string
+        - name: age
+          in: query
+          description: age of pet
+          schema:
+            type: number
+            format: int32
+      responses:
+        '200':
+          description: successful operation
+        '400':
+          description: Invalid status value
+
+    patch:
+      tags:
+        - default
+      summary: Update a Pet
+      description: Partially update an existing pet
+      operationId: updatePet
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/PetUpdateRequest'
+      responses:
+        '200':
+          description: Pet updated successfully
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Pet'
+        '400':
+          description: Invalid input
+        '404':
+          description: Pet not found
+
+components:
+  schemas:
+    PetUpdateRequest:
+      type: object
+      description: Payload for updating a pet
+      properties:
+        name:
+          type: string
+          description: New name for the pet
+        age:
+          type: integer
+          format: int32
+          description: Updated age
+        type:
+          type: string
+          description: Type of pet
+        date:
+          $ref: "#/components/schemas/Date"
+          description: Reference description of Date schema
+      required:
+        - name
+
+    Pet:
+      type: object
+      description: Pet object
+      properties:
+        id:
+          type: integer
+          format: int64
+        name:
+          type: string
+        age:
+          type: integer
+          format: int32
+        type:
+          type: string
+
+    Date:
+      type: string
+      format: date
+      description: Component description of Date schema
+