Error when trying to switch back to the original browser window using intern leadfoot

Question

I'm getting the following error when I call switchToWindow(handle): null value in entry: name=null

The original window is still open when I try to switch and handle is not null or empty. Here is the code I'm using:

var session = this.remote;
var handle;

return session
    .get('http://www.google.com')
    .getCurrentWindowHandle()
    .then(function (currentHandle) {
        console.log('handle: ' + currentHandle);
        handle = currentHandle;
    })
    .execute(function() {
        var newWindow = window.open('https://www.instagram.com/', 'insta');
    })
    .switchToWindow('insta')
    .closeCurrentWindow()
    .then(function () {
        console.log('old handle: ' + handle);
    })
    .sleep(2000)
    .switchToWindow(handle);

Answer 1

A Command chain is a single JavaScript expression. This means that all the arguments to all the calls in the chain are evaluated at once, synchronously. When handle is assigned in a then callback near the top of the chain, it won't affect the switchToWindow call at the bottom of the chain, because the value of handle had already been evaluated before the then callback ever executed.

If you want to keep a reference to a value early in a chain, and use it later, both uses should be in then callbacks.

return session
    ...
    .then(function (currentHandle) {
        handle = currentHandle;
    })
    ...
    .then(function () {
        return session.switchToWindow(handle);
    });