Add support for testValue definitions in nested props only

testing.js

@@ -31,13 +31,15 @@ function getTestValues(propsSpec) {
           }
         }
       } else if (typeof prop.properties === 'object') {
-        // if properties is an object, and the `testValue` is also an object,
-        // we can recurse and assign the results directly
-        if (typeof memo[name] === 'object') {
+        // if properties is an object, we can recurse and assign the results directly
+        const hasBaseValue = typeof memo[name] === 'object'
+        const hasUndefinedBase = typeof memo[name] === 'undefined'
+        if (hasBaseValue || hasUndefinedBase) {
+          // the base object could have an undefined test value, if so, we set up an empty object
+          if (hasUndefinedBase) memo[name] = {}
           Object.assign(memo[name], getTestValues(prop.properties))
-        } else if (typeof memo[name] === 'undefined') {
-          // do nothing, there is no test value and thats ok
         } else {
+          // otherwise we should throw an error - testValues should match the properties type
           throw new Error(
             `The property "${name}" has a "properties" key, which requires an array or object type, but its "testValue" is ${JSON.stringify(
               memo[name]

testing.test.js

@@ -69,7 +69,7 @@ test('no test values used at all', () => {
       },
     },
   })
-  expect(res).toEqual({})
+  expect(res).toEqual({ base: { array: [{}], object: {} } })
 })
 
 test('errors when a multi-type array has a test value at base and in properties', () => {
@@ -140,5 +140,5 @@ test('sub-properties define test values but base property is undefined', () => {
       },
     },
   })
-  expect(res).toEqual({})
+  expect(res).toEqual({ base: { foo: 'nested' } })
 })