idea-test.js

describe("", function () {
    it("", function () {
        var frame = window.open("blah.html?id=10");
        return inFrame(frame, function () {
            expect(window.location).toEndWith("id=10");
        });
    });
});

Where inFrame establishes the test runner DSL inside the frame with an proxy test reporter that forwards messages back to the parent context’s current test report, and where inFrame returns a promise that resolves when all expectation messages that were sent have been received.

And where the callback on inFrame is serialized via toString to the test context.