composeWith sub-generator not mocking as expected

[wulfgarpro]

I'm trying to test my generator, which, using composeWith, relies on a sub-generator (generator-express):

this.composeWith(require.resolve('generator-express/app'), {dirname: this.props.app_name, createDirectory: 'n'});
My test is trying to mock said sub-generator:

var deps = [
      [helpers.createDummyGenerator(), require.resolve('generator-express/app')]
];

describe('generator-cesium/app Test', () => {
    beforeEach(() => {
        return helpers.run(path.join(__dirname, '../generators/app'))
            .inDir(path.join(__dirname, 'tmp'))
            .withPrompts({
                viewerContext: '/',  // eslint-disable-line camelcase
                appName: 'app'       // eslint-disable-line camelcase
            })
            .withGenerators(deps)
    });
...

But, I keep getting the following error:

Error [ERR_UNHANDLED_ERROR]: Unhandled error. (TypeError: Cannot read property 'match' of undefined)

      at Immediate.setImmediate (node_modules/generator-express/node_modules/yeoman-generator/lib/index.js:406:18)

The error, indicating that the sub-generator is still being executed, leads me to believe that the mock is not actually working?

[chippawah]

I'm having the same issue. There's a command that's being run within the sub-generator that should be mocked and therefore not run.

[wulfgarpro]

I have a SO question here outlining the issue. AFAICT, the only answer I've been given, as light on detail as it is, does not work, and worryingly, the user who answered purports to be a contributor to the Yeoman project 😟.

[eddiemonge]

@wulfgarpro @SBoudrias is one of the core contributors and wrote the sub-generator stuff.

[mshima]

The problem is that when you composeWith a generator path, it will load that path and ignore the registered generators/mocks.
https://github.com/yeoman/generator/blob/006e13e485fcaeed613c78d594884bc1c69961e5/lib/index.js#L707-L709

The mock is registered to the environment with the namespace.
To use the mock you should use namespaces instead of paths.

As far as I can see this is not a bug so I am closing it.