feat: lodash base findIndex, find (not implementation)

src/Algorithm/sort/radixSort/__tests__.ts

@@ -1,8 +1,8 @@
 /*
  * @Author: Rainy
  * @Date: 2019-11-14 19:25:01
- * @LastEditors: Rainy
- * @LastEditTime: 2019-12-01 12:00:19
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 11:20:52
  */
 
 import { bucketSort } from '.';
@@ -11,10 +11,19 @@ import { NumberArrayMap } from 'types';
 const input: NumberArrayMap = [3, 2, 1, 2, 3, 21, 123, 312, 123, 11];
 const input2: NumberArrayMap = [3, 2, 1, 2, 3, 21, 123, 312, 123, 12345, 2222, 111, 11];
 
+
+test('bucketSort([]) should be []', () => {
+  expect(bucketSort([])).toEqual([]);
+});
+
 test('bucketSort([], 0) should be []', () => {
   expect(bucketSort([], 0)).toEqual([]);
 });
 
+test('bucketSort([3], 1) should be [3]', () => {
+  expect(bucketSort([3])).toEqual([3]);
+});
+
 test('bucketSort([3], 1) should be [3]', () => {
   expect(bucketSort([3], 1)).toEqual([3]);
 });

src/Algorithm/sort/radixSort/index.ts

@@ -1,16 +1,16 @@
 /*
  * @Author: Rainy
  * @Date: 2019-11-14 19:25:01
- * @LastEditors: Rainy
- * @LastEditTime: 2019-12-01 11:39:39
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 11:15:28
  */
 
 import { NumberArrayMap } from 'types';
 import { insertionSort } from '../insertionSort';
 
 export function bucketSort(
   arr: NumberArrayMap,
-  bucketSize: number
+  bucketSize?: number,
 ): NumberArrayMap {
   if (arr.length === 0) {
     return arr;

src/Array/arrayMove/index.ts

@@ -1,11 +1,11 @@
 /*
  * @Author: Rainy
  * @Date: 2019-11-14 19:25:01
- * @LastEditors: Rainy
- * @LastEditTime: 2019-11-24 20:11:42
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 10:24:02
  */
 
-import { AnyArrayMap } from '../../types';
+import { AnyArrayMap } from 'types';
 
 export function arrayMove(array: AnyArrayMap, from: number, to: number): AnyArrayMap {
   array = array.slice();

src/Array/find/README.md

@@ -0,0 +1,62 @@
+> 为了不污染原生的 Array 对象, 实现通过 function 来实现
+>
+> Eg:
+
+```javascript
+// prototype
+Array.prototype.find = function(predicate, /* thisArg*/) {}
+
+// ours
+function (collection, predicate) {}
+```
+
+### 原理
+
+`find` 方法对数组中的每一项元素执行一次 `predicate` 函数, 直至有一个 `predicate` 返回 `true`. 当找到了这样一个元素后, 该方法会立即返回这个元素的值, 否则返回 `undefined`. 注意`predicate` 函数会为数组中的每个索引调用即从 0 到 `length - 1`, 而不仅仅是那些被赋值的索引, 这意味着对于稀疏数组来说, 该方法的效率要低于那些只遍历有值的索引的方法.
+
+- 把传入的 `this` 转换成 `Object`对象, 需要`null`值处理 -> `O`
+
+- 取出 `Object`的 `length` -> `len`
+
+- 判断传入 `predicate` 的是否是 `function`, 抛出异常 `TypeError exception`
+
+- 设置计数器 `k = 0`
+
+- `while k < len`
+  - `kValue = O[k]`
+  - `testResult = predicate(thisArg, kValue, k, O)` -> `Boolean`
+  - `testResult is true, return kValue`
+  - `Set k to k + 1`
+- `Return undefined`
+
+### 参数
+
+- `predicate`
+
+  在数组每一项上执行的函数, 接收 3 个参数:
+
+  - `element`
+
+    当前遍历到的元素
+
+  - `index` 可选
+
+    当前遍历到的索引
+
+  - `array` 可选
+
+    数组本身
+
+- `thisArg` 可选
+
+  执行回调时用作`this`的对象
+
+### 返回值
+
+返回数组中满足提供的测试函数的第一个元素的值. 否则返回 `undefined`
+
+### 参考
+
+[Find MDN](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Array/find)
+
+[TC39 Find](https://tc39.es/ecma262/#sec-array.prototype.find)

src/Array/find/__test__.ts

@@ -0,0 +1,12 @@
+/*
+ * @Author: Rainy
+ * @Date: 2019-11-14 19:25:01
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 10:32:42
+ */
+
+import { _find } from '.';
+
+// test('_isArray([]) should true', () => {
+//   expect(_isArray([])).toBe(true);
+// });

src/Array/find/index.ts

@@ -0,0 +1,11 @@
+/*
+ * @Author: Rainy
+ * @Date: 2019-11-14 19:25:01
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 10:31:47
+ */
+
+import { isAbsType } from 'utils/type';
+
+export function _find(collection: any, predicate: any): any {
+}

src/Array/isArray/index.ts

@@ -1,12 +1,12 @@
 /*
  * @Author: Rainy
  * @Date: 2019-11-14 19:25:01
- * @LastEditors: Rainy
- * @LastEditTime: 2019-12-02 20:16:48
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 11:09:21
  */
 
 import { isAbsType } from '../../utils/type';
 
 export function _isArray(target: any): boolean {
-    return isAbsType(target).toLowerCase() === 'array';
+  return isAbsType(target).toLowerCase() === 'array';
 }

src/lodash/.internal/__test__/__tests__.ts

@@ -0,0 +1,88 @@
+/*
+ * @Author: Rainy
+ * @Date: 2019-12-29 10:44:01
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 11:25:32
+ */
+
+import { baseFindIndex } from '../baseFindIndex';
+
+const input: any = [1, 2, 3, 3, 4, 5, 6, 7];
+
+const inputString: any = ['a', 'b', 'c'];
+
+test(`baseFindIndex(${input}, (item: any, index: number, array: any[]) => {
+    return item > 3;
+  }) should be 3`, () => {
+  expect(
+    baseFindIndex(
+      input,
+      (item: any, index: number, array: any[]) => {
+        return item > 3;
+      }
+    )).toEqual(4);
+});
+
+test(`baseFindIndex(${input}, (item: any, index: number, array: any[]) => {
+    return item > 2;
+  }) should be 2`, () => {
+  expect(
+    baseFindIndex(
+      input,
+      (item: any, index: number, array: any[]) => {
+        return item > 2;
+      }
+    )).toEqual(2);
+});
+
+test(`baseFindIndex(${input}, (item: any, index: number, array: any[]) => {
+  return item > 2;
+}, 0) should be 2`, () => {
+expect(
+  baseFindIndex(
+    input,
+    (item: any, index: number, array: any[]) => {
+      return item > 2;
+    },
+    0
+  )).toEqual(2);
+});
+
+test(`baseFindIndex(${input}, (item: any, index: number, array: any[]) => {
+  return item > 2;
+}, 4, 4) should be 4`, () => {
+expect(
+  baseFindIndex(
+    input,
+    (item: any, index: number, array: any[]) => {
+      return item > 2;
+    },
+    4,
+    4
+  )).toEqual(4);
+});
+
+test(`baseFindIndex(${inputString}, (item: any, index: number, array: any[]) => {
+    return item === 'a';
+  }) should be 0`, () => {
+  expect(
+    baseFindIndex(
+        inputString,
+      (item: any, index: number, array: any[]) => {
+        return item === 'a';
+      }
+    )).toEqual(0);
+});
+
+
+test(`baseFindIndex(${inputString}, (item: any, index: number, array: any[]) => {
+    return item === 'd';
+  }) should be 0`, () => {
+  expect(
+    baseFindIndex(
+        inputString,
+      (item: any, index: number, array: any[]) => {
+        return item === 'd';
+      }
+    )).toEqual(-1);
+});

src/lodash/.internal/baseFindIndex.ts

@@ -0,0 +1,34 @@
+/*
+ * @Author: Rainy
+ * @Date: 2019-12-29 10:29:48
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 11:31:44
+ */
+import { AnyArrayMap, WithParamsReturnAnyFunction } from '../../types';
+
+
+/**
+ * @export
+ * @param {AnyArrayMap} array
+ * @param {WithParamsReturnAnyFunction} predicate
+ * @param {number} fromIndex
+ * @param {number} fromRight
+ * @returns {number}
+ */
+export function baseFindIndex(
+    array: AnyArrayMap,
+    predicate: WithParamsReturnAnyFunction,
+    fromIndex: number = 0,
+    fromRight?: number
+): number {
+  const { length } = array;
+  let index = fromIndex + (fromRight ? 1 : -1);
+
+  while ((fromRight ? --index : ++index < length)) {
+      if (!!predicate(array[index], index, array)) {
+        return index;
+      }
+  }
+
+  return -1;
+}

src/types/index.d.ts

@@ -2,8 +2,8 @@
 /*
  * @Author: Rainy
  * @Date: 2019-11-14 19:55:36
- * @LastEditors: Rainy
- * @LastEditTime: 2019-12-01 11:57:26
+ * @LastEditors  : Rainy
+ * @LastEditTime : 2019-12-29 11:01:00
  */
 
 export class ClassType {}
@@ -33,6 +33,10 @@ export type ObjectMap<V> = {
 // Function
 export type NullFunction = () => null;
 
+export type AnyFunction = () => any;
+
+export type WithParamsReturnAnyFunction = (...arg: any) => any;
+
 export type BaseFunction = () => BaseValueType;
 
 export type MixedFunction = () => MixedValueType;