feat: support chunk

docs/.vitepress/items/array.ts

@@ -1,5 +1,6 @@
 export const arrayItems = [
   { text: 'at', link: '/array/at' },
+  { text: 'chunk', link: '/array/chunk' },
   { text: 'uniq', link: '/array/uniq' },
   { text: 'uniqBy', link: '/array/uniq-by' },
   { text: 'find', link: '/array/find' },

docs/array/chunk.md

@@ -0,0 +1,24 @@
+# chunk
+
+Chunking an `array`. The passed `size` indicates the length of the chunk.
+
+### Usage
+
+```ts
+import { chunk } from 'rattail'
+
+chunk([1, 2, 3], 2) // return [[1, 2], [3]]
+```
+
+### Arguments
+
+| Arg    | Type     | Defaults |
+| ------ | -------- | -------- |
+| `arr`  | `Array`  |          |
+| `size` | `number` | `1`      |
+
+### Return
+
+| Type    |
+| ------- |
+| `Array` |

docs/zh/array/chunk.md

@@ -0,0 +1,24 @@
+# chunk
+
+对 `数组` 进行分块。传递的 `size` 表示块的长度。
+
+### 使用
+
+```ts
+import { chunk } from 'rattail'
+
+chunk([1, 2, 3], 2) // return [[1, 2], [3]]
+```
+
+### 参数
+
+| 参数   | 类型     | 默认值 |
+| ------ | -------- | ------ |
+| `arr`  | `Array`  |        |
+| `size` | `number` | `1`    |
+
+### 返回值
+
+| 类型    |
+| ------- |
+| `Array` |

src/array.ts

@@ -1,4 +1,5 @@
 import { isArray } from './general'
+import { clamp } from './number'
 
 export function uniq<T>(arr: T[]) {
   return [...new Set(arr)]
@@ -80,3 +81,17 @@ export function shuffle<T>(arr: T[]): T[] {
   }
   return arr
 }
+
+export function chunk<T>(arr: T[], size = 1): T[][] {
+  size = clamp(size, 1, arr.length)
+
+  const result: T[][] = []
+  let index = 0
+
+  while (index < arr.length) {
+    result.push(arr.slice(index, index + size))
+    index += size
+  }
+
+  return result
+}

tests/array.spec.ts

@@ -10,6 +10,7 @@ import {
   find,
   at,
   shuffle,
+  chunk,
 } from '../src'
 
 it('uniq', () => {
@@ -84,3 +85,12 @@ it('shuffle', () => {
   const shuffled = shuffle([...arr])
   expect(shuffled.sort()).toEqual(arr)
 })
+
+it('chunk', () => {
+  expect(chunk([])).toEqual([])
+  expect(chunk([1, 2, 3, 4, 5])).toEqual([[1], [2], [3], [4], [5]])
+  expect(chunk([1, 2, 3, 4, 5], 0)).toEqual([[1], [2], [3], [4], [5]])
+  expect(chunk([1, 2, 3, 4, 5], 2)).toEqual([[1, 2], [3, 4], [5]])
+  expect(chunk([1, 2], 2)).toEqual([[1, 2]])
+  expect(chunk([1, 2], 3)).toEqual([[1, 2]])
+})