Node.js dependency injection

consumer.js

var declaration = require('./declaration');

declaration();
// --> assertion error 3 is not equal to 4

declaration({
  assert: {
    equal: function () {
      return true;
    }
  }
});
// --> 

declaration.js

function resolve(deps, name) {
  if (deps && deps[name]) {
    return deps[name];
  } else {
    return require(name);
  }
}

module.exports = function(deps) {  
  var assert = resolve(deps, 'assert');
  assert.equal(3,4);
};