Create module

index.ts

@@ -0,0 +1,55 @@
+/**
+ * A collection of object keys.
+ */
+export type PropertyKeys <T extends Object> = (PropertyKey & keyof T)[];
+
+/**
+ * A collection of object keys which match a type.
+ */
+export type TypedPropertyKeys <T extends Object, U> = Extract<keyof T, U>[];
+
+/**
+ * Get a collection of keys from an object.
+ * @param object
+ */
+export const getKeys = <T extends Object> (object: T): PropertyKeys<T> => {
+  if (typeof Reflect === 'object' && typeof Reflect.ownKeys === 'function')
+    return Reflect.ownKeys(object) as PropertyKeys<T>;
+
+  if (typeof Object.getOwnPropertySymbols !== 'function')
+    return Object.getOwnPropertyNames(object) as TypedPropertyKeys<T, string>;
+
+  const keys: PropertyKeys<T> = [];
+
+  return keys.concat(
+    Object.getOwnPropertyNames(object) as TypedPropertyKeys<T, string>,
+    Object.getOwnPropertySymbols(object) as TypedPropertyKeys<T, symbol>
+  );
+};
+
+/**
+ * Type definition for object property descriptors.
+ */
+export type PropertyDescriptors <T> = PropertyDescriptorMap & {
+  [P in keyof T]: TypedPropertyDescriptor<T[P]>
+};
+
+/**
+ * Get an object with all object property descriptors.
+ * @param object
+ */
+export const getDescriptors = <T extends Object> (object: T): PropertyDescriptors<T> => {
+  if (typeof Object.getOwnPropertyDescriptors === 'function')
+    return Object.getOwnPropertyDescriptors(object) as PropertyDescriptors<T>;
+
+  const descriptors = getKeys(object).reduce((descriptors, key) => {
+    const descriptor = Object.getOwnPropertyDescriptor(object, key);
+    if (descriptor)
+      descriptors[key] = descriptor;
+    return descriptors;
+  }, {} as PropertyDescriptors<T>) as PropertyDescriptors<T>;
+
+  return descriptors;
+};
+
+export default getDescriptors;