Tell Mocha to use CoffeeScript files by default

Question

I'm currently trying to set up testing in Mocha for an application I'm writing using Zappa.js. So far I've been following this tutorial, and converting what I need from JS to Coffeescript.

However I'm a little stuck with trying to run tests. I have a Makefile, which currently looks like this:

REPORTER = dot

test:
  @NODE_ENV=test ./node_modules/.bin/mocha \
    --reporter $(REPORTER) \

.PHONY: test

And I've set up my package.json file to run tests like so:

{
  "scripts": {
    "test": "make test"
  }
}

The issue I'm finding is that, because I'm trying to write my Mocha tests using Coffeescript as well, Mocha does not pick up any of my tests in the "test/" folder when I run "npm test". I know for a fact that I can tell Mocha to run .coffee files by using the following in Terminal (which works):

mocha --compilers coffee:coffee-script

What I want to know is how do I go about telling Mocha to use Coffeescript files by default?

score 5 · Accepted Answer · edited Oct 17 '14 at 19:17

OK I managed to find a way to solve my own question, so I thought I'd share in case anyone else need this.

NOTE: For CoffeeScript 1.7+ --require coffee-script needs to be changed to --require coffee-script/register

The solution is to instead create a Cakefile as opposed to a Makefile, which looks like this:

#Cakefile

{exec} = require "child_process"

REPORTER = "min"

task "test", "run tests", ->
  exec "NODE_ENV=test
    ./node_modules/.bin/mocha
    --compilers coffee:coffee-script
    --reporter #{REPORTER}
    --require coffee-script
    --require test/test_helper.coffee
    --colors
    ", (err, output) ->
      throw err if err
      console.log output

And then change the package.json to this:

#package.json

{
  "scripts": {
    "test": "cake test"
  }
}

Finally I had to install Coffeescript into the project using:

npm install coffee-script

And create a file test/test_helper.coffee, which contains global declarations for the tests.

If you want contributors to be able to execute your tests, you'll want to do `npm install coffee-script --save-dev` — Wil Moore III, Aug 16 '13 at 05:15
For CoffeeScript 1.7+ `--require coffee-script` needs to be changed to `--require coffee-script/register` http://stackoverflow.com/a/9943255/167815 — Dave James Miller, May 18 '14 at 10:38

score 4 · Answer 2 · answered Oct 15 '13 at 05:50

I configure the mocha tests directly using npm

package.json (scripts only)

"scripts": {
  "start": "node app.js",
  "start-watch": "./node_modules/.bin/node-dev app.js",
  "test": "NODE_ENV=test ./node_modules/.bin/mocha --require coffee-script --compilers coffee:coffee-script --recursive ./test",
  "test-watch": "NODE_ENV=test ./node_modules/.bin/mocha --require coffee-script --compilers coffee:coffee-script --recursive ./test --watch"
}

and then execute the test coffeescript files by running

npm test

or

npm run-script test-watch

This **does** work when using `--require coffee-script/register` — meridius, Oct 09 '16 at 14:39

score 0 · Answer 3 · answered Aug 16 '13 at 07:08

Below is a working Makefile and package.json

Makefile:

REPORTER = dot
COMPILER = coffee:coffee-script

node_modules:
    @npm install

test: node_modules
    @./node_modules/.bin/mocha --reporter $(REPORTER) --compilers $(COMPILER)

clean: node_modules
    @$(RM) -r node_modules

.PHONY: clean test

package.json (devDependencies only):

  "devDependencies": {
    "coffee-script": "~1.6.3",
    "chai": "~1.7.2",
    "mocha": "~1.12.0"
  }

Then do:

% make clean
% make test

Tell Mocha to use CoffeeScript files by default

3 Answers3