Fix deep key types

Author: NoelDeMartin

src/types/objects.test.ts

@@ -46,6 +46,8 @@ describe('Object types', () => {
                       | 'author.id'
                       | 'author.name'
                       | 'categories'
+                      | `categories.${number}`
+                      | `categories.${number}.id`
                       | 'deep'
                       | 'deep.one'
                       | 'deep.one.two'

src/types/objects.ts

@@ -15,7 +15,10 @@ export type DeepKeyOf<T, TRequired extends DeepRequired<T> = DeepRequired<T>> =
               [K in keyof TRequired]: TRequired[K] extends Function
                   ? never
                   : TRequired[K] extends Array<infer TItem>
-                    ? `${Exclude<K, symbol>}.${number}.${DeepKeyOf<TItem>}`
+                    ?
+                          | `${Exclude<K, symbol>}`
+                          | `${Exclude<K, symbol>}.${number}`
+                          | `${Exclude<K, symbol>}.${number}.${DeepKeyOf<TItem>}`
                     : TRequired[K] extends object
                       ?
                             | {