fix get children dependency bug

[s97712]

[coveralls]

Pull Request Test Coverage Report for Build 28

• 7 of 7 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 100.0%

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Totals
Change from base Build 27:	0.0%
Covered Lines:	226
Relevant Lines:	226

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💛 - Coveralls

[gnaeus]

Sorry for a long wait. If I clearly understand, your PR allows to register dependencies of parent component services inside child component providers. But it can results to unpredictable behaviour.

For example... Suppose we have an SPA with two pages: Home and About. And two services: AppService and PageService.

class PageService {
  dispose() {
    // ...
  }
}

class AppService {
  @inject pageService: PageService;
}

We register AppService in App component level.

@provider(AppService)
class App extends React.Component {
  render() {
    return (
      <Router>
        <Route path="/home" component={Home} />
        <Route path="/about" component={About} />
      </Router>
    )
  }
}

Then we register PageService in concrete page's provider. And inject AppService into each page.

@provider(PageService)
class Home extends React.Component {
  @inject appService: AppService;
  // ...
}

@provider(PageService)
class About extends React.Component {
  @inject appService: AppService;
  // ...
}

But wait... If user starts our SPA from /home route, then appService lives in App provider and appService.pageService in Home provider. But if user starts from /about route, appService.pageService will be stored in About provider. So our initialization logic implicitly depends on route visiting sequence.

Moreover, if user navigates from /home to /about then Home page provider will be unmounted. And appService.pageService will be disposed by calling pageService.dispose() inside react-ioc.

The right way is to move up PageService registration to App component provider.

@provider(AppService, PageService)
class App extends React.Component // ...

[s97712]

Thank for your reply. Sub-dependency is very common and useful in angular. I really like this feature, and will try to fix the problem.