Update Jest configuration file.

Author: trekhleb

README.md

@@ -174,14 +174,22 @@ tree is being used.
 npm install
 ```
 
+**Run ESLint**
+
+You may want to run it to check code quality.
+
+```
+npm run lint
+```
+
 **Run all tests**
 ```
 npm test
 ```
 
 **Run tests by name**
 ```
-npm test -- -t 'LinkedList'
+npm test -- 'LinkedList'
 ```
 
 **Playground**
@@ -192,7 +200,7 @@ tests for it in `./src/playground/__test__/playground.test.js`.
 Then just simply run the following command to test if your playground code works as expected:
 
 ```
-npm test -- -t 'playground'
+npm test -- 'playground'
 ```
 
 ## Useful Information

README.zh-CN.md

@@ -147,7 +147,7 @@ npm test
 
 **按照名称执行测试**
 ```
-npm test -- -t 'LinkedList'
+npm test -- 'LinkedList'
 ```
 
 **Playground**
@@ -157,7 +157,7 @@ npm test -- -t 'LinkedList'
 然后，只需运行以下命令来测试你的 Playground 是否按无误:
 
 ```
-npm test -- -t 'playground'
+npm test -- 'playground'
 ```
 
 ## 有用的信息

README.zh-TW.md

@@ -145,7 +145,7 @@ npm test
 
 **以名稱執行該測試**
 ```
-npm test -- -t 'LinkedList'
+npm test -- 'LinkedList'
 ```
 **練習場**
 
@@ -154,7 +154,7 @@ npm test -- -t 'LinkedList'
 接著直接執行下列的指令來測試你練習的 code 是否如預期運作：
 
 ```
-npm test -- -t 'playground'
+npm test -- 'playground'
 ```
 
 ## 有用的資訊

jest.config.js

@@ -1,5 +1,23 @@
 module.exports = {
+  // The bail config option can be used here to have Jest stop running tests after
+  // the first failure.
+  bail: false,
+
+  // Indicates whether each individual test should be reported during the run.
   verbose: false,
+
+  // Indicates whether the coverage information should be collected while executing the test
   collectCoverage: false,
+
+  // The directory where Jest should output its coverage files.
   coverageDirectory: './coverage/',
+
+  // If the test path matches any of the patterns, it will be skipped.
+  testPathIgnorePatterns: ['<rootDir>/node_modules/'],
+
+  // If the file path matches any of the patterns, coverage information will be skipped.
+  coveragePathIgnorePatterns: ['<rootDir>/node_modules/'],
+
+  // The pattern Jest uses to detect test files.
+  testRegex: '(/__tests__/.*|(\\.|/)(test|spec))\\.jsx?$',
 };