add mockGoferScript export

[Josh Willing]

This would be a convenience function to combine with the fm-gofer library.

The usage should look something like this:

Example interface describing API:

Example usage:

// mock data example
// (use similar call signature to return a string or number,
//    they should all be stringified automatically to simulate
//    how FM passes only strings to JS functions)
mockGoferScript(
    'Fetch Data',
    {
        "name": "Josh",
        "animal": "Humanish",
    },
   { delay: 1500 } // simulate slow FM script
)

// custom callback example 
mockGoferScript(
    'Fetch Data',
    // if possible, these three params should be automatically destructured and passed to this fn (via currying?)
    (callbackName, promiseID, parameter) => {
        // do some custom logic, perhaps simulating intermittent record lock errors
        window[callbackName](promiseID, JSON.stringify({name: 'Josh', animal: 'Humanish'});
    },
    { delay: 123 }
)

It should be able to accept any of the following as the second param

1. a void fn with args callbackName, promiseID, and parameter
2. an object or array, which will be stringified and returned via callback automatically
3. a string, which will be returned verbatim automatically
4. a number whiwh will be stringified and returned automatically.

[Josh Willing]

resultFromFM should be optional and possibly should live in the options object. One advantage of putting it in the options object is it will have a key name, which will be more readable.

current:

declare const mockGoferScript: (scriptName: string, resultFromFM: Record<string, unknown> | any[] | number | string | ResultFunction | AsyncResultFunction, options?: {
    delay?: number | undefined;
    returnError?: boolean | undefined;
    logParams?: boolean | undefined;
}) => void;

proposed:

declare const mockGoferScript: (scriptName: string, resultFromFM?: Record<string, unknown> | any[] | number | string | ResultFunction | AsyncResultFunction, options?: {
    delay?: number | undefined;
    returnError?: boolean | undefined;
    logParams?: boolean | undefined;
}) => void;

// or...
declare const mockGoferScript: (scriptName: string, options?: {
    resultFromFM?: Record<string, unknown> | any[] | number | string | ResultFunction | AsyncResultFunction;
    delay?: number | undefined;
    returnError?: boolean | undefined;
    logParams?: boolean | undefined;
}) => void;

[Josh Willing]

consider adding options param to regular mockScript, but exclude returnError, because that's gofer specific.

[Josh Willing]

Maybe add ability to import json data from a file instead of having to inline it in the mocks (even though you could mock one script per file, theoretically).

[Josh Willing]

I changed my mind about adding support for a path to a mock json file because this can already be elegantly done like this:

mockGoferScript('My Script', {
  resultFromFM: () => import("./mocks/data.json"),
  logParams: true,
  delay: 500,
});

So with that out of the way, I'm feeling pretty comfortable with the current design and close to merging.