Cannot run Mocha with CoffeeScript - 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.

Answer 3

Apparently, a change in Mocha made in April 2018 (softly) deprecated the --compilers option. In the command line you now get:
(node:27864) DeprecationWarning: "--compilers" will be removed in a future version of Mocha; see https://git.io/vdcSr for more info
Like the link says, this can easily be fixed by just not using --compilers and using this new (simplified) mocha.opts options:
--require coffeescript/register
test/*.coffee
The last line is needed to make Mocha understand it should now use *.coffee files as test files. This seems not to be covered with the --require option.

Answer 4

mocha --require coffeescript/register
Source: https://github.com/mochajs/mocha/wiki/compilers-deprecation

Answer 5

with the latest update of mocha the the require statement must written in package.json file as
"mocha":{
"require":"coffeescript",
"reporter":"spec"
},

Answer 6

I needed two changes to my mocha args to get this to work:
--require coffee-script/register
--compilers coffee:coffee-script/register