fix(sample-gen): should return json literal example (#6827)

* fix(sample-gen): should return json literal example

* test(sample-gen): should return json literal example

src/core/plugins/samples/fn.js

@@ -203,7 +203,17 @@ export const sampleFromSchemaGeneric = (schema, config={}, exampleOverride = und
 
     // if json just return
     if(!respectXML) {
-      return sample
+      // return if sample does not need any parsing
+      if(typeof sample !== "string") {
+        return sample
+      }
+      // check if sample is parsable or just a plain string
+      try {
+        return JSON.parse(sample)
+      } catch(e) {
+        // sample is just plain string return it
+        return sample
+      }
     }
 
     // recover missing type

test/unit/core/utils.js

@@ -1535,6 +1535,29 @@ describe("utils", () => {
       // Then
       expect(res).toEqual(0)
     })
+
+    it("should stringify object when literal string example is provided if json content-type", () => {
+      // Given
+      const expected = "<MyObject></MyObject>"
+      const res = getSampleSchema({
+        type: "object",
+      }, "text/json", {}, expected)
+
+      // Then
+      expect(res).toEqual(JSON.stringify(expected))
+    })
+
+    it("should parse valid json literal example if json content-type", () => {
+      // Given
+      const expected = {test: 123}
+      const res = getSampleSchema({
+        type: "object",
+      }, "text/json", {}, JSON.stringify(expected))
+
+      // Then
+      const actual = JSON.parse(res)
+      expect(actual.test).toEqual(123)
+    })
   })
 
   describe("paramToIdentifier", () => {