add test showcasing ref property siblings being lost in OpenAPI 3.1

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

@@ -1976,6 +1976,20 @@ public void testTitleProperty() {
         final Map testProperties = Collections.unmodifiableMap(openAPI.getComponents().getSchemas().get("ModelWithTitledProperties").getProperties());
 
         Assertions.assertEquals("Simple-Property-Title", codegen.fromProperty("simpleProperty", (Schema) testProperties.get("simpleProperty")).title);
+        Assertions.assertEquals("All-Of-Ref-Property-Title", codegen.fromProperty("refProperty", (Schema) testProperties.get("allOfRefProperty")).title);
+    }
+
+    @Test
+    public void testTitlePropertyOAS31refSibling() {
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_1/property-title.yaml");
+        new InlineModelResolver().flatten(openAPI);
+        final DefaultCodegen codegen = new DefaultCodegen();
+        codegen.setOpenAPI(openAPI);
+
+        final Map testProperties = Collections.unmodifiableMap(openAPI.getComponents().getSchemas().get("ModelWithTitledProperties").getProperties());
+
+        Assertions.assertEquals("Simple-Property-Title", codegen.fromProperty("simpleProperty", (Schema) testProperties.get("simpleProperty")).title);
+        Assertions.assertEquals("All-Of-Ref-Property-Title", codegen.fromProperty("refProperty", (Schema) testProperties.get("allOfRefProperty")).title);
         Assertions.assertEquals("Ref-Property-Title", codegen.fromProperty("refProperty", (Schema) testProperties.get("refProperty")).title);
     }
 
@@ -5009,4 +5023,25 @@ public void testSingleRequestParameter_hasSingleParamTrue() {
         // When & Then
         assertThat(codegenOperation.hasSingleParam).isTrue();
     }
+
+    /**
+     * Starting with OpenAPI 3.1, it is legal to have a $ref be a sibling to other properties.
+     * This test ensures that any sibling properties, "title" in this case, do not get lost while resolving the ref.
+     */
+    @Test
+    public void testSiblingPropertyWithRefInOAS31() {
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_1/property-title.yaml");
+        final DefaultCodegen codegen = new DefaultCodegen();
+        codegen.setOpenAPI(openAPI);
+        Map<String, Schema> properties = openAPI.getComponents().getSchemas().get("ModelWithTitledProperties").getProperties();
+
+        // These always worked
+        Assert.assertEquals("Simple-Property-Title",
+                codegen.fromModel("dummy", properties.get("simpleProperty")).getTitle());
+        Assert.assertEquals("All-Of-Ref-Property-Title",
+                codegen.fromModel("dummy", properties.get("allOfRefProperty")).getTitle());
+        // This is new in OpenAPI 3.1, and should work now: "title" is a sibling to the "$ref" and should not be lost
+        Assert.assertEquals("Ref-Property-Title",
+                codegen.fromModel("dummy", properties.get("refProperty")).getTitle());
+    }
 }

modules/openapi-generator/src/test/resources/3_0/property-title.yaml

@@ -19,9 +19,9 @@ components:
         simpleProperty:
           type: string
           title: Simple-Property-Title
-        refProperty:
+        allOfRefProperty:
           type: string
-          title: Ref-Property-Title
+          title: All-Of-Ref-Property-Title
           allOf:
             - $ref: '#/components/schemas/RefObject'
       type: object

modules/openapi-generator/src/test/resources/3_1/property-title.yaml

@@ -0,0 +1,33 @@
+openapi: 3.1.0
+paths:
+  /foo:
+    get:
+      responses:
+        '200':
+          description: ok
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/test'
+info:
+  title: Title on Properties
+  version: "1.0"
+components:
+  schemas:
+    ModelWithTitledProperties:
+      properties:
+        simpleProperty:
+          type: string
+          title: Simple-Property-Title
+        refProperty:
+          type: string
+          title: Ref-Property-Title
+          $ref: '#/components/schemas/RefObject'
+        allOfRefProperty:
+          type: string
+          title: All-Of-Ref-Property-Title
+          allOf:
+            - $ref: '#/components/schemas/RefObject'
+      type: object
+    RefObject:
+      type: string