fix(sample-gen): oas3 form-data object should generate example (#7355)

src/core/plugins/oas3/components/request-body.jsx

@@ -165,14 +165,16 @@ const RequestBody = ({
               const useInitialValue = useInitialValFromSchemaSamples || useInitialValFromEnum
               
               let initialValue = ""
-              if(type === "array" && !useInitialValue) {
+              if (type === "array" && !useInitialValue) {
                 initialValue = []
-              } else if (useInitialValue) {
+              }
+              if (type === "object" || useInitialValue) {
                 // TODO: what about example or examples from requestBody could be passed as exampleOverride
                 initialValue = getSampleSchema(prop, false, {
                   includeWriteOnly: true
                 })
               }
+
               if (typeof initialValue !== "string" && type === "object") {
                initialValue = stringify(initialValue)
               }

test/e2e-cypress/static/documents/features/request-body/multipart/default-views.yaml

@@ -0,0 +1,28 @@
+openapi: 3.0.3
+info:
+  title: multipart/form-data schema object
+  version: 0.0.1
+paths:
+  /test:
+    post:
+      requestBody:
+        content:
+          multipart/form-data:
+            schema:
+              type: object
+              properties:
+                file:
+                  type: string
+                  format: binary
+                parameters:
+                  "$ref": "#/components/schemas/TestBody"
+      responses:
+        200:
+          description: ok
+components:
+  schemas:
+    TestBody:
+      type: object
+      properties:
+        stuff:
+          type: string

test/e2e-cypress/tests/features/oas3-request-body-default-views.js

@@ -0,0 +1,16 @@
+describe("OAS3 default views", () => {
+  describe("multipart/form-data", () => {
+    it("should display calculated object string, when no examples provided (#7268)", () => {
+      cy.visit(
+        "/?url=/documents/features/request-body/multipart/default-views.yaml",
+      )
+        .get("#operations-default-post_test")
+        .click()
+        // Expand Try It Out
+        .get(".try-out__btn")
+        .click()
+        .get(".parameters-col_description textarea")
+        .should("contains.text", "\"stuff\": \"string\"")
+    })
+  })
+})