noImplicitAny checks don't work for a setter parameter of Object.defineProperty #8410

Activity

1. mhegazy commented on May 1, 2016

   

   Mohamed Hegazy (mhegazy)

   on May 1, 2016

   Contributor

   More actions

   it gets a contextual type from the declaration, see https://github.com/Microsoft/TypeScript/blob/master/lib/lib.d.ts#L81.

   we could change the definition of defineProperty to use TypedPropertyDescriptor instead of PropertyDescriptor, that will make your setter argument inferred from declaration, so it will be {} and not any, which would be closer to an error. but that would be a breaking change.
2. mhegazy commented on May 1, 2016

   

   Mohamed Hegazy (mhegazy)

   on May 1, 2016

   Contributor

   More actions

   so just to be clear, the reported behavior is expected given the lib.d.ts definition. if there is anything to do is to change the definition in lib.d.ts
3. Mohamed Hegazy (mhegazy)

   added

   SuggestionAn idea for TypeScriptAn idea for TypeScript

   In DiscussionNot yet reached consensusNot yet reached consensus

   on May 1, 2016
4. falsandtru commented on May 1, 2016

   

   falsandtru (falsandtru)

   on May 1, 2016

   ContributorAuthor

   More actions

   related: #8373
5. Daniel Rosenwasser (DanielRosenwasser)

   added

   Domain: lib.d.tsThe issue relates to the different libraries shipped with TypeScriptThe issue relates to the different libraries shipped with TypeScript

   on May 2, 2016
6. kitsonk commented on May 2, 2016

   

   Kitson Kelly (kitsonk)

   on May 2, 2016

   Contributor

   More actions

   I don't think they are actually related. It is being properly contextually typed as any. What I think Mohamed Hegazy (@mhegazy) is suggesting is that it might be worth this being implemented in lib.d.ts in the future, as it stands at the moment it will always be non-implicit any because of the contextual typing:

   interface PropertyDescriptor<T> {
       configurable?: boolean;
       enumerable?: boolean;
       value?: T;
       writable?: boolean;
       get? (): T;
       set? (v: T): void;
   }
   
   interface ObjectConstructor {
       defineProperty<T>(o: any, p: string, attributes: PropertyDescriptor<T>): any;
   }

   I suspect there are a few other places too that would need to be adjusted.
7. Mohamed Hegazy (mhegazy)

   added

   Working as IntendedThe behavior described is the intended behavior; this is not a bugThe behavior described is the intended behavior; this is not a bug

   and removed

   In DiscussionNot yet reached consensusNot yet reached consensus

   on May 16, 2016
8. mhegazy commented on May 16, 2016

   

   Mohamed Hegazy (mhegazy)

   on May 16, 2016

   Contributor

   More actions

   As noted earlier, there is a context type passed through, and that suppresses the noImplicitAny errors. you can get a better behavior by defining an extra overload of define property as:

   interface ObjectConstructor {
       defineProperty<T>(o: any, p: string, attributes: TypedPropertyDescriptor<T>): any;
   }

   it is not clear there is much value in changing the lib.d.ts definitions for everybody though.
9. Mohamed Hegazy (mhegazy)

   closed this as completedon May 16, 2016
10. microsoft

    locked and limited conversation to collaborators on Jun 19, 2018