feat(pick): accept a callback for advanced picking

docs/object/pick.mdx

@@ -1,6 +1,6 @@
 ---
 title: pick
-description: Pick only the desired attributes from an object
+description: Pick only the desired properties from an object
 ---
 
 ## Basic usage
@@ -19,3 +19,18 @@ const fish = {
 
 _.pick(fish, ['name', 'source']) // => { name, source }
 ```
+
+### Predicate function
+
+The `pick` function can also accept a predicate function as the filter argument. This allows for more complex filtering logic beyond simple key inclusion or exclusion.
+
+```ts
+import * as _ from 'radashi'
+
+const source = { a: 1, b: 2, c: 3, d: 4 }
+
+_.pick(source, (value, key) => {
+  return value % 2 === 0 // Include only even values
+})
+// => { b: 2, d: 4 }
+```

src/object/pick.ts

@@ -1,20 +1,30 @@
+import { type FilteredKeys, filterKey, isArray, type KeyFilter } from 'radashi'
+
 /**
  * Pick a list of properties from an object into a new object
  */
-export function pick<T extends object, TKeys extends keyof T>(
+export function pick<T extends object, F extends KeyFilter<T, keyof T>>(
   obj: T,
-  keys: TKeys[],
-): Pick<T, TKeys> {
+  filter: F,
+): Pick<T, FilteredKeys<T, F>>
+
+export function pick<T extends object>(
+  obj: T,
+  filter: KeyFilter<T, keyof T> | null,
+) {
   if (!obj) {
-    return {} as Pick<T, TKeys>
+    return {}
+  }
+  let keys: (keyof T)[] = filter as any
+  if (isArray(filter)) {
+    filter = null
+  } else {
+    keys = Reflect.ownKeys(obj) as (keyof T)[]
   }
-  return keys.reduce(
-    (acc, key) => {
-      if (Object.hasOwnProperty.call(obj, key)) {
-        acc[key] = obj[key]
-      }
-      return acc
-    },
-    {} as Pick<T, TKeys>,
-  )
+  return keys.reduce((acc, key) => {
+    if (filterKey(obj, key, filter)) {
+      acc[key] = obj[key]
+    }
+    return acc
+  }, {} as T)
 }

tests/object/pick.test.ts

@@ -79,4 +79,11 @@ describe('pick', () => {
       a: 2,
     })
   })
+  test('works with predicate function', () => {
+    const result = _.pick({ a: 1, b: 2, c: 3, d: 4 }, value => value % 2 === 0)
+    expect(result).toEqual({
+      b: 2,
+      d: 4,
+    })
+  })
 })