fix(core): nullable array types in 3.1.x specs (#19687)

* fix: nullable array types in 3.1.x

* fix: pass on on `getNullable` value

* chore: add generated marker

* chore: add generated marker

* Delete out

Author: joscha

bin/configs/typescript-consolidated-nullable.yaml

@@ -0,0 +1,4 @@
+generatorName: typescript
+outputDir: samples/client/others/typescript/builds/null-types-simple
+inputSpec: modules/openapi-generator/src/test/resources/3_1/null-types-simple.yaml
+templateDir: modules/openapi-generator/src/main/resources/typescript

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

@@ -1268,6 +1268,7 @@ private Schema processNormalize31Spec(Schema schema, Set<Schema> visitedSchemas)
                 as.setMaxItems(schema.getMaxItems());
                 as.setExtensions(schema.getExtensions());
                 as.setXml(schema.getXml());
+                as.setNullable(schema.getNullable());
                 as.setUniqueItems(schema.getUniqueItems());
                 if (schema.getItems() != null) {
                     // `items` is also a json schema

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

@@ -63,6 +63,7 @@ public class ModelUtils {
 
     private static final String URI_FORMAT = "uri";
 
+    // These types are for 3.0.x only; 3.1 also has a `null` type as well
     private static final Set<String> OPENAPI_TYPES = Set.of("array", "integer", "number", "boolean", "string", "object");
 
     private static final String generateAliasAsModelKey = "generateAliasAsModel";

modules/openapi-generator/src/test/resources/3_1/null-types-simple.yaml

@@ -0,0 +1,37 @@
+openapi: 3.1.0
+info:
+  title: ""
+  version: ""
+components:
+  schemas:
+    WithNullableType:
+      type: object
+      required:
+        # This simplifies the output
+        - arrayDataOrNull
+        - stringDataOrNull
+        - oneofOrNull
+      properties:
+        arrayDataOrNull:
+          items:
+            $ref: "#/components/schemas/SomeObject"
+          type:
+            - array
+            - 'null'
+        # This was working when this fixture was introduced,
+        # but we need to make sure we don't regress
+        stringDataOrNull:
+          type:
+            - string
+            - 'null'
+        # This was working when this fixture was introduced,
+        # but we need to make sure we don't regress
+        oneofOrNull:
+          oneOf:
+            - $ref: "#/components/schemas/SomeObject"
+            - type: 'null'
+    SomeObject:
+      type: object
+      properties:
+        data:
+          type: string

samples/client/others/typescript/.gitattributes

@@ -0,0 +1 @@
+builds/**/* linguist-generated=true