Instance property used in reassigning method causes implicit `any` in `checkJs`

[DanielRosenwasser]

// ./foo.ts

class Foo {
    constructor() {
        this.foo = "Hello";
    }
    slicey() {
        this.foo = this.foo.slice();
    }
}

// ./tsconfig.json

{
  "compilerOptions": { "strict": true },
  "files": ["./foo.ts"]
}

Current Behavior

'foo' implicitly has type 'any' because it does not have a type annotation and is referenced directly or indirectly in its own initializer.ts(7022)

Proposed Behavior

If an implicit any is going to be inferred, but foo has an initializer in the constructor, it should always infer the type from the initializer.

[DanielRosenwasser]

Found using checkJs on the following code https://github.com/jleeson/iris/blob/be259e3a5d11657cbb5775bd96aae48cb8fbd368/src/views/View.js#L12

[sandersn]

This has been around since at least 2.3. It's related to over-eager type resolution in Javascript, which causes a circularity in type checking. It appears in a number of places, but this will probably be the most commonly encountered.

It's easy to work around with a type annotation or a stage 3 property declaration.