Type of variable incorrectly `any` when used in function body in its own initializer

[vvakame]

reproduction code.

interface IResource<T> {
    $save(): void;
}
interface IResourceClass<T> {
    new (): T;
    query(callback: Function): IResourceArray<T>;
}
interface IResourceArray<T> extends Array<T> {
}

function makeClass<T, U>(): U {
    return null;
}

interface IFoo {
    foo: string;
}
interface IFooResource extends IResource<IFooResource>, IFoo {
}
interface IFooResourceClass extends IResourceClass<IFooResource> {
}

var Clazz = makeClass<IFooResource, IFooResourceClass>();
var array = Clazz.query(() => {
    var obj1 = array[1];
    obj1.foo;
    obj1.$save();
    // I'm expected an error occured following line.
    // but tsc 1.0.1 and master/HEAD are compiled it.
    obj1.notExsists;
});

var obj2 = array[1];
obj2.foo;
obj2.$save();
// I'm expected an error occured following line.
// but tsc master/HEAD are compiled it. tsc 1.0.1 are decline it.
obj2.notExsists;

in tsc 1.0.1

$ tsc --version
Version 1.0.1.0
$ tsc test.ts
/Users/vvakame/tmp/test.ts(38,6): error TS2094: The property 'notExsists' does not exist on value of type 'IFooResource'.

in master/HEAD 2a106bf

$ node ~/work/TypeScript/built/local/tsc.js test.ts
$ echo $?
0

in playground (I think playground are works perfectly)
http://goo.gl/4jjVHi

in real world
https://gist.github.com/vvakame/1272d6b94febc18d0bd4
https://github.com/borisyankov/DefinitelyTyped/blob/master/angularjs/angular-resource.d.ts

[RyanCavanaugh]

Reduced. When a variable refers to itself inside a function body in its own initializer, that should not cause the type of the variable to be any.

function noWitness(n: any): string {
    return '';
}

// x: any, should be x: string
var x = noWitness(() => { x; });
x.ewjoew; // should be error

[vladima]

By Design as existing behavior matches spec 5.1 Variable statements:

• If the declaration includes an initializer but no type annotation, and if the initializer doesn’t directly or indirectly reference the variable, the widened type (section 3.9) of the initializer expression becomes the type of the variable. If the initializer directly or indirectly references the variable, the type of the variable becomes the Any type.

Reassigning this to Jonathan to either confirm the resolution or to clarify what new behavior we would like to see.

[RyanCavanaugh]

This is a breaking change and runs counter to the witnessing spec that Anders sent out. We should at least discuss this.

[sophiajt]

We should add Anders witness spec work to the official spec. Assigning to Anders to make update.