coffee

Coffee

Test command line on Node.js.

---

Install

$ npm i coffee --save-dev

Usage

Coffee is useful for test command line in test frammework (like Mocha).

describe('cat', function() {
  it('should concat input', function(done) {
    const coffee = require('coffee');
    coffee.spawn('cat')
      .write('1')
      .write('2')
      .expect('stdout', '12')
      .expect('code', 0)
      .end(done);
  })
})

You can also use fork for spawning Node processes.

coffee.fork('/path/to/file.js', [ 'args' ])
  .expect('stdout', '12\n')
  .expect('stderr', '34\n')
  .expect('code', 0)
  .end(done);

In file.js

console.log(12);
console.error(34);

Support multiple process coverage with nyc

Recommend to use nyc for coverage, you can use any test frammework supported by nyc.

API

coffee.spawn

Run command using child_process.spawn, then return Coffee instance.

Arguments see child_process.spawn

coffee.fork

Run command using child_process.fork, then return Coffee instance.

Arguments see child_process.fork

coffee.Coffee

Assertion object

coffee.expect(type, expected)

Assert type with expected value, expected value can be string, regular expression, and array.

coffee.spawn('echo', [ 'abcdefg' ])
  .expect('stdout', 'abcdefg')
  .expect('stdout', /^abc/)
  .expect('stdout', [ 'abcdefg', /abc/ ])
  .end(done);

Accept type: stdout, stderr, code, error

coffee.notExpect(type, expected)

The opposite assertion of expect.

coffee.write(data)

Write data to stdin, see example above.

coffee.waitForPrompt(bool)

If you set false, coffee will write stdin immediately, otherwise will wait for prompt message.

coffee.fork('/path/to/cli', [ 'abcdefg' ])
  .waitForPrompt()
  .write('tz\n')
  .write('2\n');
  .end(done);

cli process should emit prompt message:

const readline = require('readline');

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
});

function ask(q, callback) {
  process.send({ type: 'prompt' });
  rl.question(q, callback);
}

ask('What\'s your name? ', answer => {
  console.log(`hi, ${answer}`);
  ask('How many coffee do you want? ', answer => {
    console.log(`here is your ${answer} coffee`);
    rl.close();
  });
});

coffee.end(callback)

Callback will be called after completing the assertion, the first argument is Error if throw exception.

coffee.fork('path/to/cli')
  .expect('stdout', 'abcdefg')
  .end(done);

// recommended to left undefind and use promise.
const { stdout, stderr, code } = await coffee.fork('path/to/cli').end();
assert(stdout.includes(abcdefg));

coffee.debug(level)

Write data to process.stdout and process.stderr for debug

level can be

• 0 (default): pipe stdout + stderr
• 1: pipe stdout
• 2: pipe stderr
• false: disable

Alternative you can use COFFEE_DEBUG env.

coffee.coverage()

If you set false, coffee will not generate coverage.json, default: true.

coffee.beforeScript(scriptFile)

Add a hook script before fork child process run.

coffee.Rule

Assertion Rule

you could add your custom rule, see test/fixtures/extendable for more details.

const { Coffee, Rule } = require('coffee');

class FileRule extends Rule {
  assert(actual, expected, message) {
    // do sth
    return super.assert(content, pattern, message);
  }
}

class MyCoffee extends Coffee {
  constructor(...args) {
    super(...args);
    this.setRule('file', FileRule);
  }
}

LISENCE

Copyright (c) 2017 node-modules. Licensed under the MIT license.