var hello = 'hello';
var world = 'nodejs';

debugger;

var hello_world = hello + ' ' + world;
console.log(hello_world);

node-debug-tutorial git:(master) ✗ node debug helloword-debug.js
< debugger listening on port 5858
connecting... ok
break in helloword-debug.js:1
  1 var hello = 'hello';
  2 var world = 'nodejs';
  3 
debug> help
Commands: run (r), cont (c), next (n), step (s), out (o), backtrace (bt), setBreakpoint (sb), clearBreakpoint (cb),
watch, unwatch, watchers, repl, restart, kill, list, scripts, breakOnException, breakpoints, version
debug> 
debug> n
break in helloword-debug.js:2
  1 var hello = 'hello';
  2 var world = 'nodejs';
  3 
  4 debugger;
debug> repl
Press Ctrl + C to leave debug repl
> hello
'hello'

debug> n
break in helloword-debug.js:4
  2 var world = 'nodejs';
  3 
  4 debugger;
  5 
  6 var hello_world = hello + ' ' + world;
debug> n
break in helloword-debug.js:6
  4 debugger;
  5 
  6 var hello_world = hello + ' ' + world;
  7 console.log(hello_world);
  8 
debug> n
break in helloword-debug.js:7
  5 
  6 var hello_world = hello + ' ' + world;
  7 console.log(hello_world);
  8 
  9 });
debug> repl
Press Ctrl + C to leave debug repl
> hello_world
'hello nodejs'
> 
end

< Failed to open socket on port 5858, waiting 1000 ms before retrying

ps -ef|grep debug-brk|awk '{print $2}'|xargs kill -9

npm install -g node-inspector

node-inspector &

node --debug-brk app.js

node-debug app.js

➜  node-debug-tutorial git:(master) node extend.js 
node debug
hello node debug

➜  node-debug-tutorial git:(master) node-debug  extend.js
Node Inspector is now available from http://localhost:8080/debug?port=5858
Debugging `extend.js`

debugger listening on port 5858

base.call(this);

npm init .
npm install --save express
touch express-helloworld.js

var express = require('express');
var app = express();

app.get('/',function(req,res){
	res.send('hello,world');
});

app.listen(5008);

npm install -g supervisor
supervisor express-helloworld.js

➜  node-debug-tutorial git:(master) ✗ node-debug express-helloworld.js 
Node Inspector is now available from http://localhost:8080/debug?port=5858
Debugging `express-helloworld.js`

debugger listening on port 5858

curl -G -d "test=string" http://127.0.0.1:5008/

We improved stepping performance by loading the scopes and variables 
of stack frames lazily. This improvement is based on a protocol change
that affects all debug adapters.

npm install --save-dev chai
npm install --save-dev sinon
npm install --save-dev supertest
npm install --save-dev zombie

chai.should();

foo.should.be.a('string');
foo.should.equal('bar');
foo.should.have.lengthOf(3);
tea.should.have.property('flavors')
  .with.lengthOf(3);

var expect = chai.expect;

expect(foo).to.be.a('string');
expect(foo).to.equal('bar');
expect(foo).to.have.lengthOf(3);
expect(tea).to.have.property('flavors')
  .with.lengthOf(3);

var assert = chai.assert;

assert.typeOf(foo, 'string');
assert.equal(foo, 'bar');
assert.lengthOf(foo, 3)
assert.property(tea, 'flavors');
assert.lengthOf(tea.flavors, 3);

function once(fn) {
    var returnValue, called = false;
    return function () {
        if (!called) {
            called = true;
            returnValue = fn.apply(this, arguments);
        }
        return returnValue;
    };
}

it('calls the original function', function () {
    var callback = sinon.spy();
    var proxy = once(callback);

    proxy();

    assert(callback.called);
});

const request = require('supertest');
const express = require('express');

const app = express();

app.get('/user', function(req, res) {
  res.status(200).json({ name: 'tobi' });
});

request(app)
  .get('/user')
  .expect('Content-Type', /json/)
  .expect('Content-Length', '15')
  .expect(200)
  .end(function(err, res) {
    if (err) throw err;
  });

const Browser = require('zombie');

// We're going to make requests to http://example.com/signup
// Which will be routed to our test server localhost:3000
Browser.localhost('example.com', 3000);

describe('User visits signup page', function() {

  const browser = new Browser();

  before(function(done) {
    browser.visit('/signup', done);
  });

  describe('submits form', function() {

    before(function(done) {
      browser
        .fill('email',    '[email protected]')
        .fill('password', 'eat-the-living')
        .pressButton('Sign Me Up!', done);
    });

    it('should be successful', function() {
      browser.assert.success();
    });

    it('should see welcome page', function() {
      browser.assert.text('title', 'Welcome To Brains Depot');
    });
  });
});

	# features/documentation.feature
	Feature: Example feature
	  As a user of Cucumber.js
	  I want to have documentation on Cucumber
	  So that I can concentrate on building awesome applications

	  Scenario: Reading documentation
	    Given I am on the Cucumber.js GitHub repository
	    When I click on "CLI"
	    Then I should see "Running specific features"

// features/support/world.js
require('chromedriver')
var seleniumWebdriver = require('selenium-webdriver');
var {defineSupportCode} = require('cucumber');

function CustomWorld() {
  this.driver = new seleniumWebdriver.Builder()
    .forBrowser('chrome')
    .build();
}

defineSupportCode(function({setWorldConstructor}) {
  setWorldConstructor(CustomWorld)
})

// features/step_definitions/hooks.js
var {defineSupportCode} = require('cucumber');

defineSupportCode(function({After}) {
  After(function() {
    return this.driver.quit();
  });
});

// features/step_definitions/browser_steps.js
var seleniumWebdriver = require('selenium-webdriver');
var {defineSupportCode} = require('cucumber');

defineSupportCode(function({Given, When, Then}) {
  Given('I am on the Cucumber.js GitHub repository', function() {
    return this.driver.get('https://github.com/cucumber/cucumber-js/tree/master');
  });

  When('I click on {stringInDoubleQuotes}', function (text) {
    return this.driver.findElement({linkText: text}).then(function(element) {
      return element.click();
    });
  });

  Then('I should see {stringInDoubleQuotes}', function (text) {
    var xpath = "//*[contains(text(),'" + text + "')]";
    var condition = seleniumWebdriver.until.elementLocated({xpath: xpath});
    return this.driver.wait(condition, 5000);
  });
});

npm install --save-dev gulp
npm install --save-dev gulp-mocha
npm install --save-dev gulp-istanbul

var gulp = require('gulp');
var istanbul = require('gulp-istanbul');
var mocha = require('gulp-mocha'); 

gulp.task('test', function (cb) {
  gulp.src(['db/**/*.js'])
    .pipe(istanbul()) // Covering files
    .on('finish', function () {
      gulp.src(['test/*.js'])
        .pipe(mocha())
        .pipe(istanbul.writeReports()) // Creating the reports after tests runned
        .on('end', cb);
    });
});

gulp.task('default',['test'], function() {
  gulp.watch(['./db/**/*','./test/**/*'], ['test']);
});

gulp.task('watch',['test'], function() {
  gulp.watch(['./db/**/*','./test/**/*'], ['test']);
});

  "scripts": {
    "start": "./node_modules/.bin/supervisor ./bin/www",
    "test": "./node_modules/.bin/mocha -u tdd"
  },

node --debug app.js
Debugger listening on 127.0.0.1:5858

let vm = require('vm')
let debug = vm.runInDebugContext('Debug')

function test() {}

debug.setListener((event, execState, eventData, data) => {
    if (event != debug.DebugEvent.Break) return

    var script   = eventData.func().script().name()
    var line     = eventData.sourceLine()
    var col      = eventData.sourceColumn()

    var location = script + ":" + line + ":" + col

    var funcName = eventData.func().name()
    if (funcName != "") {
        location += " " + funcName + "()"
    }

    console.log(location)
})

debug.setBreakPoint(test, 0, 0)

test()
// /Users/sang/workspace/github/node-debug-tutorial/a.js:3:17 test()

       {
            "type": "node",
            "request": "attach",
            "name": "Attach (Inspector Protocol)",
            "port": 9229,
            "protocol": "inspector"
        },
        {
            "type": "node",
            "request": "attach",
            "name": "Attach (Legacy Protocol)",
            "port": 5858,
            "protocol": "legacy"
        },

Debugger listening on ws://127.0.0.1:9229/3e4a2794-11ac-4471-bf3c-a5849e92e20a
For help see https://nodejs.org/en/docs/inspector

http://[host:port]/json/list 
http://127.0.0.1/9229/json/list 

1、 打开chrome://inspect
2、 点击Remote Target下面的inspect来打开chrome devtools