[typescript-fetch] Fix code generation for oneOf cases without discriminator (#19219)

* Add samples using `oneOf` without discriminator

* Fix typescript-fetch code gen for `oneOf` without discriminator

* Return `{}` instead of original `json`

Author: odiak

bin/configs/typescript-fetch-oneOf.yaml

@@ -0,0 +1,4 @@
+generatorName: typescript-fetch
+outputDir: samples/client/petstore/typescript-fetch/builds/oneOf
+inputSpec: modules/openapi-generator/src/test/resources/3_0/typescript-fetch/oneOf.yaml
+templateDir: modules/openapi-generator/src/main/resources/typescript-fetch

modules/openapi-generator/src/main/resources/typescript-fetch/modelOneOf.mustache

@@ -36,6 +36,8 @@ export function {{classname}}FromJSONTyped(json: any, ignoreDiscriminator: boole
         return {{{.}}}FromJSONTyped(json, true);
     }
     {{/oneOf}}
+
+    return {} as any;
 {{/discriminator}}
 }
 

modules/openapi-generator/src/test/resources/3_0/typescript-fetch/oneOf.yaml

@@ -0,0 +1,37 @@
+openapi: 3.0.0
+info:
+  version: 1.0.0
+  title: testing oneOf without discriminator
+servers:
+  - url: http://localhost:3000
+paths:
+  /test:
+    get:
+      operationId: test
+      responses:
+        200:
+          description: OK
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/TestResponse'
+components:
+  schemas:
+    TestResponse:
+      oneOf:
+        - $ref: "#/components/schemas/TestA"
+        - $ref: "#/components/schemas/TestB"
+    TestA:
+      type: object
+      properties:
+        foo:
+          type: string
+      required:
+        - foo
+    TestB:
+      type: object
+      properties:
+        bar:
+          type: string
+      required:
+        - bar

samples/client/petstore/typescript-fetch/builds/oneOf/.openapi-generator-ignore

@@ -0,0 +1,23 @@
+# OpenAPI Generator Ignore
+# Generated by openapi-generator https://github.com/openapitools/openapi-generator
+
+# Use this file to prevent files from being overwritten by the generator.
+# The patterns follow closely to .gitignore or .dockerignore.
+
+# As an example, the C# client generator defines ApiClient.cs.
+# You can make changes and tell OpenAPI Generator to ignore just this file by uncommenting the following line:
+#ApiClient.cs
+
+# You can match any string of characters against a directory, file or extension with a single asterisk (*):
+#foo/*/qux
+# The above matches foo/bar/qux and foo/baz/qux, but not foo/bar/baz/qux
+
+# You can recursively match patterns against a directory, file or extension with a double asterisk (**):
+#foo/**/qux
+# This matches foo/bar/qux, foo/baz/qux, and foo/bar/baz/qux
+
+# You can also negate patterns with an exclamation (!).
+# For example, you can ignore all files in a docs folder with the file extension .md:
+#docs/*.md
+# Then explicitly reverse the ignore rule for a single file:
+#!docs/README.md

samples/client/petstore/typescript-fetch/builds/oneOf/.openapi-generator/FILES

@@ -0,0 +1,8 @@
+apis/DefaultApi.ts
+apis/index.ts
+index.ts
+models/TestA.ts
+models/TestB.ts
+models/TestResponse.ts
+models/index.ts
+runtime.ts

samples/client/petstore/typescript-fetch/builds/oneOf/.openapi-generator/VERSION

@@ -0,0 +1 @@
+7.8.0-SNAPSHOT

samples/client/petstore/typescript-fetch/builds/oneOf/apis/DefaultApi.ts

@@ -0,0 +1,54 @@
+/* tslint:disable */
+/* eslint-disable */
+/**
+ * testing oneOf without discriminator
+ * No description provided (generated by Openapi Generator https://github.com/openapitools/openapi-generator)
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+import * as runtime from '../runtime';
+import type {
+  TestResponse,
+} from '../models/index';
+import {
+    TestResponseFromJSON,
+    TestResponseToJSON,
+} from '../models/index';
+
+/**
+ * 
+ */
+export class DefaultApi extends runtime.BaseAPI {
+
+    /**
+     */
+    async testRaw(initOverrides?: RequestInit | runtime.InitOverrideFunction): Promise<runtime.ApiResponse<TestResponse>> {
+        const queryParameters: any = {};
+
+        const headerParameters: runtime.HTTPHeaders = {};
+
+        const response = await this.request({
+            path: `/test`,
+            method: 'GET',
+            headers: headerParameters,
+            query: queryParameters,
+        }, initOverrides);
+
+        return new runtime.JSONApiResponse(response, (jsonValue) => TestResponseFromJSON(jsonValue));
+    }
+
+    /**
+     */
+    async test(initOverrides?: RequestInit | runtime.InitOverrideFunction): Promise<TestResponse> {
+        const response = await this.testRaw(initOverrides);
+        return await response.value();
+    }
+
+}

samples/client/petstore/typescript-fetch/builds/oneOf/apis/index.ts

@@ -0,0 +1,3 @@
+/* tslint:disable */
+/* eslint-disable */
+export * from './DefaultApi';

samples/client/petstore/typescript-fetch/builds/oneOf/index.ts

@@ -0,0 +1,5 @@
+/* tslint:disable */
+/* eslint-disable */
+export * from './runtime';
+export * from './apis/index';
+export * from './models/index';

samples/client/petstore/typescript-fetch/builds/oneOf/models/TestA.ts

@@ -0,0 +1,61 @@
+/* tslint:disable */
+/* eslint-disable */
+/**
+ * testing oneOf without discriminator
+ * No description provided (generated by Openapi Generator https://github.com/openapitools/openapi-generator)
+ *
+ * The version of the OpenAPI document: 1.0.0
+ * 
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+import { mapValues } from '../runtime';
+/**
+ * 
+ * @export
+ * @interface TestA
+ */
+export interface TestA {
+    /**
+     * 
+     * @type {string}
+     * @memberof TestA
+     */
+    foo: string;
+}
+
+/**
+ * Check if a given object implements the TestA interface.
+ */
+export function instanceOfTestA(value: object): value is TestA {
+    if (!('foo' in value) || value['foo'] === undefined) return false;
+    return true;
+}
+
+export function TestAFromJSON(json: any): TestA {
+    return TestAFromJSONTyped(json, false);
+}
+
+export function TestAFromJSONTyped(json: any, ignoreDiscriminator: boolean): TestA {
+    if (json == null) {
+        return json;
+    }
+    return {
+        
+        'foo': json['foo'],
+    };
+}
+
+export function TestAToJSON(value?: TestA | null): any {
+    if (value == null) {
+        return value;
+    }
+    return {
+        
+        'foo': value['foo'],
+    };
+}
+