Weak Type Detection - not being detected with const

[alan-agius4]

TypeScript Version: 2.5.2

Code

function foo(_opts: Options) {
    // do something;
    return;
}

interface Options {
    data?: any;
    show?: boolean;
}

interface OptionsExtended extends Options {
    title?: string;
}

const opts = {
    show: true,
    title: "title"
};

// this works
foo(opts);

// this doesn't
foo({
    show: true,
    title: "title"
});

Expected behavior:
Both of them to emit an error

Actual behavior:
the first one works and doesn't emit an error

[kitsonk]

This doesn't have to do with weak type detection. This has to do with excess property checks between fresh object literals and inferred types. I just explained it here.