Cannot run Mocha with CoffeeScript

Question

Makefile - Content:

REPORTER = dot  all: build  build:     @./node_modules/coffee-script/bin/coffee \         -c \         -o lib src  clean:     rm -rf lib     mkdir lib  watch:     @./node_modules/coffee-script/bin/coffee \         -o lib \         -cw src  test:     @./node_modules/mocha/bin/mocha \         --reporter $(REPORTER) \         test/*.coffee  .PHONY: build clean watch test 

The project root directory has a test folder with two files: mocha.opts and example.coffee

example.coffee - Content

describe "feature", ->    it "should add two numbers", ->        (2+2).should.equal 4 

On running make test, getting the following error:

cribe 'feature',       ^^^^^^^^^  node.js:201         throw e; // process.nextTick error, or 'error' event on first tick               ^ SyntaxError: Unexpected string     at Module._compile (module.js:429:25)     at Object..js (module.js:459:10)     at Module.load (module.js:348:31)     at Function._load (module.js:308:12)     at Module.require (module.js:354:17)     at require (module.js:370:17)     at /home/my_username/testcode/coffeepress/node_modules/mocha/bin/_mocha:261:27     at Array.forEach (native)     at load (/home/my_username/testcode/coffeepress/node_modules/mocha/bin/_mocha:258:9)     at Object.<anonymous> (/home/my_username/testcode/coffeepress/node_modules/mocha/bin/_mocha:249:1)     at Module._compile (module.js:441:26)     at Object..js (module.js:459:10)     at Module.load (module.js:348:31)     at Function._load (module.js:308:12)     at Array.0 (module.js:479:10)     at EventEmitter._tickCallback (node.js:192:40) 

Running Mocha with js files succeeds, but cannot get it to run with CoffeeScript. I really want to - for code brevity.

Please guide.

Answer 1

As of Mocha 1.0:

coffee-script is no longer supported out of the box. CS and similar transpilers may be used by mapping the file extensions (for use with --watch) and the module name. For example --compilers coffee:coffee-script with CoffeeScript 1.6- or --compilers coffee:coffee-script/register with CoffeeScript 1.7+.

(Quoting http://visionmedia.github.io/mocha/#compilers-option) So, you need to add the line

--compilers coffee:coffee-script/register 

or, for CS <= 1.6.x,

--compilers coffee:coffee-script 

to your mocha.opts file.

Answer 2

From CoffeeScript 1.7 onwards, the option should be:

--compilers coffee:coffee-script/register 

An issue was filed on Mocha's github site.