mocha : how to run multiple JS test files under separate process environment

Question

I am new to Mocha so this might probably be a trivial question but couldn't yet find an answer:

I have a simple NodeJS project with the below package.json

{
  "name": "test",
  "version": "1.0.0",
  "description": "test",
  "main": "index.js",
  "scripts": {
    "test": "mocha"
  },
  "author": "davide talesco",
  "license": "ISC",
  "devDependencies": {
    "chai": "^4.0.2",
    "mocha": "^3.4.2"
  }
}

and the following 2 tests files under test folder:

test1.js

process.env.NODE_ENV = 'test';

var chai = require('chai');
var should = chai.should();

describe('Test setProp', function(){
  it('env variable should be test', function(done){
    process.env.NODE_ENV.should.be.equal('test');
    return done();
  });
});

test2.js

process.env.NODE_ENV = 'prod';

var chai = require('chai');
var should = chai.should();

describe('Test setProp', function(){
  it('env variable should be prod', function(done){
    process.env.NODE_ENV.should.be.equal('prod');
    return done();
  });
});

when I run npm test the first test complete succesfully whilst the second fails as per below

ie-macp-davidt:crap davide_talesco$ npm test

> [email protected] test /Users/davide_talesco/development/crap
> mocha



  Test setProp
    1) env variable should be test

  Test setProp
    ✓ env variable should be prod


  1 passing (16ms)
  1 failing

  1) Test setProp env variable should be test:

      AssertionError: expected 'prod' to equal 'test'
      + expected - actual

      -prod
      +test

      at Context.<anonymous> (test/test1.js:11:36)



npm ERR! Test failed.  See above for more details.

its pretty clear that the tests are running under the same process... my question is : how can I make them run under completely separate processes so each one can set its own environment?

Thanks,

Davide

Answer 1

One of the most simple ways is to use Unix find command:

find ./test -name '*.js' -exec mocha \{} \;

I'd recommend to use local mocha binaries to avoid troubles in case it isn't installed globally:

find ./test -name '*.js' -exec ./node_modules/.bin/mocha \{} \;

If you want to add that to package.json, please note that backslashes should be escaped:

...
"scripts": {
    "test": "find ./test -name '*.js' -exec ./node_modules/.bin/mocha \\{} \\;"
},
...