From ffd79fe1ec6c59cb3684a84c15b66761aa186bf1 Mon Sep 17 00:00:00 2001
From: Alec Larson <1925840+aleclarson@users.noreply.github.com>
Date: Wed, 26 Jun 2024 13:54:42 -0400
Subject: [PATCH 1/4] feat(pick): accept a callback for advanced picking

---
 src/object/pick.ts | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/object/pick.ts b/src/object/pick.ts
index d5fbd45e..e1bab4ad 100644
--- a/src/object/pick.ts
+++ b/src/object/pick.ts
@@ -1,20 +1,20 @@
+import { type FilteredKeys, type KeyFilter, reduceKeys } from "radashi";
+
 /**
  * Pick a list of properties from an object into a new object
  */
-export function pick<T extends object, TKeys extends keyof T>(
-  obj: T,
-  keys: TKeys[],
-): Pick<T, TKeys> {
-  if (!obj) {
-    return {} as Pick<T, TKeys>
-  }
-  return keys.reduce(
-    (acc, key) => {
-      if (Object.hasOwnProperty.call(obj, key)) {
-        acc[key] = obj[key]
-      }
-      return acc
-    },
-    {} as Pick<T, TKeys>,
-  )
+export function pick<T extends object, F extends KeyFilter<T, keyof T>>(
+	obj: T,
+	filter: F,
+): Pick<T, FilteredKeys<T, F>> {
+	if (!obj) return {} as any;
+	return reduceKeys(
+		obj,
+		filter,
+		(acc, value, key) => {
+			acc[key] = value;
+			return acc;
+		},
+		{} as any,
+	);
 }

From 3df170c7da86eee71b204725c3edfa4672d017bd Mon Sep 17 00:00:00 2001
From: Alec Larson <1925840+aleclarson@users.noreply.github.com>
Date: Sun, 7 Jul 2024 19:04:51 -0400
Subject: [PATCH 2/4] stop using reduceKeys

This saves us 77 bytes.
---
 src/object/pick.ts | 38 ++++++++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 14 deletions(-)

diff --git a/src/object/pick.ts b/src/object/pick.ts
index e1bab4ad..c2bd8897 100644
--- a/src/object/pick.ts
+++ b/src/object/pick.ts
@@ -1,20 +1,30 @@
-import { type FilteredKeys, type KeyFilter, reduceKeys } from "radashi";
+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, F extends KeyFilter<T, keyof T>>(
-	obj: T,
-	filter: F,
-): Pick<T, FilteredKeys<T, F>> {
-	if (!obj) return {} as any;
-	return reduceKeys(
-		obj,
-		filter,
-		(acc, value, key) => {
-			acc[key] = value;
-			return acc;
-		},
-		{} as any,
-	);
+  obj: T,
+  filter: F,
+): Pick<T, FilteredKeys<T, F>>
+
+export function pick<T extends object>(
+  obj: T,
+  filter: KeyFilter<T, keyof T> | null,
+) {
+  if (!obj) {
+    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 (filterKey(obj, key, filter)) {
+      acc[key] = obj[key]
+    }
+    return acc
+  }, {} as T)
 }

From 34be3ef9bd45b5e8a013916698b1af179332fe90 Mon Sep 17 00:00:00 2001
From: Alec Larson <1925840+aleclarson@users.noreply.github.com>
Date: Sun, 7 Jul 2024 19:08:01 -0400
Subject: [PATCH 3/4] update `pick` docs

---
 docs/object/pick.mdx | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/docs/object/pick.mdx b/docs/object/pick.mdx
index cad2a5b3..7aed8f03 100644
--- a/docs/object/pick.mdx
+++ b/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 }
+```

From b6e11ec41f0c4cf16e125934dc79a8074032cef0 Mon Sep 17 00:00:00 2001
From: Alec Larson <1925840+aleclarson@users.noreply.github.com>
Date: Sun, 7 Jul 2024 19:10:25 -0400
Subject: [PATCH 4/4] add a test

---
 tests/object/pick.test.ts | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tests/object/pick.test.ts b/tests/object/pick.test.ts
index d4c381d7..36921354 100644
--- a/tests/object/pick.test.ts
+++ b/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,
+    })
+  })
 })