Implement `context` for `@Factory` decorator

[vabatta]

Description

This PR implements the change needed to add the context to the @Factory decorator. The current behaviour is the following:

• The initial context available is passed through DataFactory.createForClass(User).generate<InitialContext>(10, { ... });
• After each @Factory decorator the returned values are added to the context as well as the final value with the class property key (e.g. @Factory() => { first, last } readonly name: string the context will be { first, last, name })

Refers to

Issue https://github.com/edwardanthony/nestjs-seeder/issues/6

Testing

Run the local sample.

$> cd sample

For local MongoDB (you need docker).

$> docker-compose up -d

Build.

$> npm run build

Run the seeder.

$> node dist/sample/src/seeder

Check your MongoDB.

[edwardanthony]

Thank you so much for the PR. I'll test this as soon as I can.

[vabatta]

@edwardanthony This misses the updates to README.md though. Would you be fine to do it yourself or shall I?

[edwardanthony]

It's fine for now. I'll try to figure out the use case and update the README, I'll let you know if otherwise.

[vabatta]

@edwardanthony An important note is that the rule of one is kept by the Schema as the initialContext is begin overwritten by the @Factory methods. See the issue for another possible feature #6 .

[vabatta]

This is stale as the feature is rolled out already.