After upgrading TypeScript, Angular controller registration now fails to compile

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Since all of the properties of IController are optional, I believe the errors you are seeing are a result of the new checking for “Weak Types” in TypeScript 2.4. Check this link from Microsoft for details. Also check this related Github issue.

Some relevant quotes from Microsoft:

In TypeScript 2.4, we’re adding a similar check for what we call weak
types. Any type that contains only optional properties is considered a
weak type since it provides few restrictions on what can be assigned
to it.

…

In TypeScript 2.4, it’s now an error to assign anything to a weak type
when there’s no overlap in properties.

…

You can think of this as TypeScript “toughening up” the weak
guarantees of these types to catch what would otherwise be silent
bugs.

Since this is a breaking change, you may need to know about the
workarounds which are the same as those for strict object literal
checks:

  1. Declare the properties if they really do exist.
  2. Add an index signature to the weak type (i.e. [propName: string]: {}).
  3. Use a type assertion (i.e. opts as Options).

Edit: Based on this information, a simple solution would then be to implement one of the methods defined in IController. For example, as mentioned by @Amy in the comments, you could just define an empty $onInit method in your controller.

Edit: For the sake of completeness, here’s the full code:

export class TopMenuController implements angular.IController {
  static $inject = ["$templateCache", "Restangular"];

  $onInit() { }

  constructor(
      private readonly $templateCache: angular.ITemplateCacheService,
      private readonly restangular: Restangular.IElement) {
  }
}

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