How can I dynamically generate test cases in javascript/node?

Question

The nose testing framework (for python) supports dynamically generating test cases at run-time (the following, from the documentation, results in five distinct test cases):

def test_evens():     for i in range(0, 5):         yield check_even, i, i*3  def check_even(n, nn):     assert n % 2 == 0 or nn % 2 == 0 

How can I achieve this result using javascript frameworks such as mocha or qunit? (I am not attached to any particular framework at this point.)

My use-case is writing a test runner to monitor several items on an external server. I would provide a list of resource URLs. Each test attempts to poll that resource and returns success or failure depending on what it finds. I have a prototype built in python (using nose) but would like to implement in node.js if I can. Eventually, this would be included in a CI setup.

Answer 1

Yes you can dynamically created test suites with cases using Mocha. I have installed mocha globally npm install -g mocha and I use should.

var should = require('should');  var foo = 'bar';  ['nl', 'fr', 'de'].forEach(function(arrElement) {   describe(arrElement + ' suite', function() {     it('This thing should behave like this', function(done) {       foo.should.be.a.String();       done();     });     it('That thing should behave like that', function(done) {       foo.should.have.length(3);       done();     });   }); }); 

Answer 2

If you want to dynamically create It() tests using data obtained asynchronously, you can (ab)use the before() hook with a placeholder It() test to ensure mocha waits until before() is run. Here's the example from my answer to a related question, for convenience:

before(function () {     console.log('Let the abuse begin...');     return promiseFn().         then(function (testSuite) {             describe('here are some dynamic It() tests', function () {                 testSuite.specs.forEach(function (spec) {                     it(spec.description, function () {                         var actualResult = runMyTest(spec);                         assert.equal(actualResult, spec.expectedResult);                     });                 });             });         }); });  it('This is a required placeholder to allow before() to work', function () {     console.log('Mocha should not require this hack IMHO'); });