From 6350d1d19167d04b5b33df391455f5e7fd9f7a4a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Felix=20K=C3=B6nig?= <de.felix.koenig@gmail.com>
Date: Mon, 19 Feb 2024 04:06:26 +0100
Subject: [PATCH] make `title` available to templates for ref properties
 (#17881)

Even though `title` is technically for the title of the API itself,
it's possible to set it for properties as well.
Right now, the `title` property is available in templates for regular properties,
but for ref-properties it gets lost right here.
This seemed rather surprising to me, so I think it's better to fix.
---
 .../openapitools/codegen/DefaultCodegen.java  |  3 ++
 .../codegen/DefaultCodegenTest.java           | 13 +++++++++
 .../test/resources/3_0/property-title.yaml    | 29 +++++++++++++++++++
 3 files changed, 45 insertions(+)
 create mode 100644 modules/openapi-generator/src/test/resources/3_0/property-title.yaml

diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
index 813a310e077..cabc8915b3d 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
@@ -4235,6 +4235,9 @@ public class DefaultCodegen implements CodegenConfig {
             if (original.getMinimum() != null) {
                 property.setMinimum(String.valueOf(original.getMinimum().doubleValue()));
             }
+            if (original.getTitle() != null) {
+                property.setTitle(original.getTitle());
+            }
         }
 
         // set the default value
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java
index 1d6a5978343..693ba0662e4 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/DefaultCodegenTest.java
@@ -1916,6 +1916,19 @@ public class DefaultCodegenTest {
         Assert.assertFalse(codegen.fromProperty("customerCode", (Schema) requestProperties.get("customerCode")).deprecated);
     }
 
+    @Test
+    public void testTitleProperty() {
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/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());
+
+        Assert.assertEquals("Simple-Property-Title", codegen.fromProperty("simpleProperty", (Schema) testProperties.get("simpleProperty")).title);
+        Assert.assertEquals("Ref-Property-Title", codegen.fromProperty("refProperty", (Schema) testProperties.get("refProperty")).title);
+    }
+
     @Test
     public void testDeprecatedRef() {
         final OpenAPI openAPI = TestUtils.parseSpec("src/test/resources/3_0/model-deprecated.yaml");
diff --git a/modules/openapi-generator/src/test/resources/3_0/property-title.yaml b/modules/openapi-generator/src/test/resources/3_0/property-title.yaml
new file mode 100644
index 00000000000..a7474f08afe
--- /dev/null
+++ b/modules/openapi-generator/src/test/resources/3_0/property-title.yaml
@@ -0,0 +1,29 @@
+openapi: 3.0.1
+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
+          allOf:
+            - $ref: '#/components/schemas/RefObject'
+      type: object
+    RefObject:
+      type: string