fix(sample-gen): parameter array missing items fallback

* fixes swagger-api#7375

Author: tim-lai

src/core/plugins/samples/fn.js

@@ -500,6 +500,10 @@ export const sampleFromSchemaGeneric = (schema, config={}, exampleOverride = und
   }
 
   if(type === "array") {
+    if (!items) {
+      return
+    }
+
     let sampleArray
     if(respectXML) {
       items.xml = items.xml || schema?.xml || {}

test/e2e-cypress/static/documents/features/parameter-array-missing-items.yaml

@@ -0,0 +1,24 @@
+openapi: 3.0.0
+info:
+  title: test
+  version: "1.0.0"
+paths:
+  /example1:
+    get:
+      description: test fetching
+      parameters:
+        - in: query
+          name: basicName
+          content: 
+            application/json:
+              schema:
+                type: object
+                properties:
+                  color:
+                    oneOf:
+                      - type: array # invalid definition b/c type: array is missing 'items'
+                      - type: string
+                      - type: integer
+      responses:
+        '200':
+          description: successfull fetch

test/e2e-cypress/tests/features/parameter-array-missing-items.js

@@ -0,0 +1,10 @@
+describe("Parameter - Invalid definition with missing array 'items' (#7375)", () => {
+  it("should render gracefully with fallback to default value", () => {
+    cy.visit("/?url=/documents/features/parameter-array-missing-items.yaml")
+      .get("#operations-default-get_example1")
+      .click()
+      .get("tbody > tr > .parameters-col_description textarea")
+      .should("exist")
+      .should("contains.text", "{}")
+  })
+})