I'm not quite sure I understand you, but it sounds like a case for `Promise.resolve(value)`[1] – that's what I do whenever I don't know if something will be a Promise or an already-resolved value. `Promise.resolve(value)` returns a Promise that immediately resolves with `value` or whatever `value` resolves to if it's a Promise – no need to do any checks yourself, no need to nest Promises inside Promises inside Promises.

For example, imagine you have a charting library and you want to draw a chart, but you don't know if the data is available already or if it's being loaded asynchronously. You can just write:

    // `drawChart(data)` is a synchronous function
    // `data` may be the data itself or a promise that resolves to the data
    Promise.resolve(data).then(drawChart)

For me, this is actually the killer feature of Promises, avoiding callback hell is just a nice side-effect. Once you start thinking of Promises as placeholders for values that may or may not be known already (rather than just an abstraction of the `callback(err, value)` pattern), you can write some really elegant code.

[1] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...