Add unit tests for examples in README, fix README examples

Author: wojtekmaj

README.md

@@ -85,7 +85,7 @@ Like `asyncFilter()`, but runs iterations non-concurrently.
 import { asyncFilterStrict } from '@wojtekmaj/async-array-utils';
 
 const indexes = [];
-await asyncFilterStrict(
+const asyncFilteredArr = await asyncFilterStrict(
   [1, 2, 3],
   async (el, index) => {
     indexes.push(index);
@@ -156,7 +156,7 @@ Like `asyncMap()`, but runs iterations non-concurrently.
 import { asyncMapStrict } from '@wojtekmaj/async-array-utils';
 
 const indexes = [];
-await asyncMapStrict(
+const asyncMappedArr = await asyncMapStrict(
   [1, 2, 3],
   async (el, index) => {
     indexes.push(index);
@@ -213,7 +213,7 @@ const largerThanZero = await asyncSomeStrict(
     return el > 0;
   },
 ); // true
-console.log(indexes); // [0, 1, 2]
+console.log(indexes); // [0]
 ```
 
 ## License

src/every.spec.js

@@ -19,6 +19,12 @@ function largerOrEqualThanZeroInRandomTime(x) {
 }
 
 describe('asyncEvery()', () => {
+  it('example from README works as described', async () => {
+    const largerThanZero = await asyncEvery([1, 2, 3], async (el) => el > 0);
+
+    expect(largerThanZero).toBe(true);
+  });
+
   it.skip('assertions below are valid for synchronous .every()', () => {
     const mapper = jest.fn().mockImplementation(largerOrEqualThanZero);
 

src/every_strict.spec.js

@@ -22,6 +22,21 @@ function largerOrEqualThanZeroInRandomTime(x) {
 }
 
 describe('asyncEvery()', () => {
+  it('example from README works as described', async () => {
+    const indexes = [];
+
+    const largerThanZero = await asyncEveryStrict(
+      [1, 2, 3],
+      async (el, index) => {
+        indexes.push(index);
+        return el > 0;
+      },
+    );
+
+    expect(largerThanZero).toBe(true);
+    expect(indexes).toEqual([0, 1, 2]);
+  });
+
   it.skip('assertions below are valid for synchronous .every()', () => {
     const mapper = jest.fn().mockImplementation(largerOrEqualThanZero);
 

src/filter.spec.js

@@ -7,6 +7,12 @@ import {
 } from '../test-utils';
 
 describe('asyncFilter()', () => {
+  it('example from README works as described', async () => {
+    const asyncFilteredArr = await asyncFilter([1, 2, 3], async (el) => el > 1);
+
+    expect(asyncFilteredArr).toEqual([2, 3]);
+  });
+
   it.skip('assertions below are valid for synchronous .filter()', () => {
     const filter = jest.fn().mockImplementation(largerThanTwo);
 

src/filter_strict.spec.js

@@ -10,6 +10,21 @@ import {
 } from '../test-utils';
 
 describe('asyncFilterStrict()', () => {
+  it('example from README works as described', async () => {
+    const indexes = [];
+
+    const asyncFilteredArr = await asyncFilterStrict(
+      [1, 2, 3],
+      async (el, index) => {
+        indexes.push(index);
+        return el > 1;
+      },
+    );
+
+    expect(asyncFilteredArr).toEqual([2, 3]);
+    expect(indexes).toEqual([0, 1, 2]);
+  });
+
   it.skip('assertions below are valid for synchronous .filter()', () => {
     const filter = jest.fn().mockImplementation(largerThanTwo);
 

src/forEach.spec.js

@@ -7,6 +7,20 @@ import {
 } from '../test-utils';
 
 describe('asyncForEach()', () => {
+  it('example from README works as described', async () => {
+    const consoleLog = jest.fn();
+
+    await asyncForEach(
+      [1, 2, 3],
+      async (el) => { consoleLog(el * 2); },
+    ); // undefined; 3 console.logs
+
+    expect(consoleLog).toHaveBeenCalledTimes(3);
+    expect(consoleLog).toHaveBeenCalledWith(2);
+    expect(consoleLog).toHaveBeenCalledWith(4);
+    expect(consoleLog).toHaveBeenCalledWith(6);
+  });
+
   it.skip('assertions below are valid for synchronous .forEach()', () => {
     const [arr, pushDuplicate] = makePushDuplicate();
     const mapper = jest.fn().mockImplementation(pushDuplicate);

src/forEach_strict.spec.js

@@ -7,6 +7,26 @@ import {
 } from '../test-utils';
 
 describe('asyncForEachStrict()', () => {
+  it('example from README works as described', async () => {
+    const consoleLog = jest.fn();
+    const indexes = [];
+
+    await asyncForEachStrict(
+      [1, 2, 3],
+      async (el, index) => {
+        indexes.push(index);
+        consoleLog(el * 2);
+      },
+    );
+
+    expect(consoleLog).toHaveBeenCalledTimes(3);
+    expect(consoleLog).toHaveBeenCalledWith(2);
+    expect(consoleLog).toHaveBeenCalledWith(4);
+    expect(consoleLog).toHaveBeenCalledWith(6);
+
+    expect(indexes).toEqual([0, 1, 2]);
+  });
+
   it.skip('assertions below are valid for synchronous .forEach()', () => {
     const [arr, pushDuplicate] = makePushDuplicate();
     const mapper = jest.fn().mockImplementation(pushDuplicate);

src/map.spec.js

@@ -8,6 +8,12 @@ import {
 } from '../test-utils';
 
 describe('asyncMap()', () => {
+  it('example from README works as described', async () => {
+    const asyncMappedArr = await asyncMap([1, 2, 3], async (el) => el * 2); // [2, 4, 6]
+
+    expect(asyncMappedArr).toEqual([2, 4, 6]);
+  });
+
   it.skip('assertions below are valid for synchronous .map()', () => {
     const mapper = jest.fn().mockImplementation(duplicate);
 

src/map_strict.spec.js

@@ -10,6 +10,21 @@ import {
 } from '../test-utils';
 
 describe('asyncMapStrict()', () => {
+  it('example from README works as described', async () => {
+    const indexes = [];
+
+    const asyncMappedArr = await asyncMapStrict(
+      [1, 2, 3],
+      async (el, index) => {
+        indexes.push(index);
+        return el * 2;
+      },
+    ); // [2, 4, 6]
+
+    expect(asyncMappedArr).toEqual([2, 4, 6]);
+    expect(indexes).toEqual([0, 1, 2]);
+  });
+
   it.skip('assertions below are valid for synchronous .map()', () => {
     const mapper = jest.fn().mockImplementation(duplicate);
 

src/reduce.spec.js

@@ -1,6 +1,16 @@
 import asyncReduce from './reduce';
 
 describe('asyncReduce()', () => {
+  it('example from README works as described', async () => {
+    const result = await asyncReduce(
+      [1, 2, 3],
+      async (tmp, cur) => tmp + cur,
+      0,
+    );
+
+    expect(result).toBe(6);
+  });
+
   it.skip('assertions below are valid for synchronous .reduce()', () => {
     const mapper = jest.fn().mockImplementation((temp, cur, idx) => [...temp, `${idx}:${cur}`]);