Add NestedKeyOf Type

core/static/bundled/utils/types.d.ts

@@ -0,0 +1,37 @@
+/**
+ * A key of an object, or of one of its descendants.
+ *
+ * Example :
+ * ```typescript
+ * interface Foo {
+ *   foo_inner: number;
+ * }
+ *
+ * interface Bar {
+ *   foo: Foo;
+ * }
+ *
+ * const foo = (key: NestedKeyOf<Bar>) {
+ *     console.log(key);
+ * }
+ *
+ * foo("foo.foo_inner");  // OK
+ * foo("foo.bar"); // FAIL
+ * ```
+ */
+export type NestedKeyOf<T extends object> = {
+  [Key in keyof T & (string | number)]: NestedKeyOfHandleValue<T[Key], `${Key}`>;
+}[keyof T & (string | number)];
+
+type NestedKeyOfInner<T extends object> = {
+  [Key in keyof T & (string | number)]: NestedKeyOfHandleValue<
+    T[Key],
+    `['${Key}']` | `.${Key}`
+  >;
+}[keyof T & (string | number)];
+
+type NestedKeyOfHandleValue<T, Text extends string> = T extends unknown[]
+  ? Text
+  : T extends object
+    ? Text | `${Text}${NestedKeyOfInner<T>}`
+    : Text;