Inconsistent type inference

[ylepikhov]

TypeScript Version: 2.3.3
See also playground

Code

interface I {

    p: string;
}

class C implements I {

    p: string;
    pp: number;
}

// no error
const c: Partial<C> = { p: "" };

function ff<T extends I>(v: Partial<T>) {

    // no error
    return v.p;
}

function f<T extends I>() {

    // error TS2322: Type '{ p: string; }' is not assignable to type 'Partial<T>'
    // why?
    const t: Partial<T> = { p: "" };
}

Expected behavior:
No error

Actual behavior:
Error at line: const t: Partial<T> = { p: "" };

[mhegazy]

Partial is not really a special type. it is just a mapping operation that happens on a type. This is already tracked by #12731

[mhegazy]

Automatically closing this issue for housekeeping purposes. The issue labels indicate that it is unactionable at the moment or has already been addressed.