Inject mocks for test suite

[leorossi]

I migrated from another DI library to awilix. I migrated the codebase but now I am struggling with test suite, since I use mocks for many of the tests I am wondering how I can inject my custom modules after I register them in the container.
Is there a way to do that?

[jeffijoe]

Not sure what you mean, could you elaborate, perhaps with an example of what you're trying to do?

If you are talking about unit tests, then you don't need Awilix in your tests because your code now uses plain constructors/factories to accept dependencies.

const service = new MyService({ db: dbMock })

[leorossi]

Thanks for the quick reply.
I am migrating also the test suite which originally was using the old library, so I am not sure the same approach will work with awilix. Here is an example

Example:
file api_utils.js is the module to be tested.

module.exports = function({ env, log  }) {
  const API_Utils = function API_Utils() {

  }
  API_Utils.prototype.doStuff = function() {
    log.info('Doing some stuff');
  }
  return API_Utils;
};

This is a sample module that can use the previous one

module.exports = function({ api_utils }) {
  apiUtils = new api_utils();
  apiUtils.doStuff();
}

The unit test file test/api_utils.js (using mocha)

...
describe('API_Utils', () => {
  it('should log "Doing some stuff"', (done) => {
    const mocks = {
      log: {
        info: function(message) {
          assert.equals(message, 'Doing some stuff');
        }
      }
    }
   // How should I inject mocks.log ?
  });
});

[jeffijoe]

First of all, your general usage seems wrong to me, since you are exporting a function which itself creates a constructor function.

This is how I would do it:

api_utils.js

module.exports = API_Utils

function API_Utils ({ env, log  }) {
  this.env = env
  this.log = log
};

API_Utils.prototype.doStuff = function() {
  this.log.info('Doing some stuff');
}

And the usage:

module.exports = function({ apiUtils }) {
  apiUtils.doStuff();
}

And finally the test — your mocks object can be used as-is.

const APIUtils = require('../path/to/api_utils.js')

describe('API_Utils', () => {
  it('should log "Doing some stuff"', (done) => {
    const mocks = {
      log: {
        info: function(message) {
          assert.equals(message, 'Doing some stuff');
        }
      }
    }
    const apiUtils = new APIUtils(mocks)
    // Use here
  });
});

Does this make sense?

[leorossi]

Yes it makes sense.

The old library required to use the

module.exports = function(dep1, dep2 ... ) {
 // here create the returnable object
}

That's why is used the same with awilix. Will test soon and update (or close) the issue. Thanks for now

[leorossi]

Ok I managed to understand better how to refactor the codebase and make it simpler.
I have another question but I'll close this issue and open another, after searching for previous similar issues. Thanks.