Add Jest for Basic Testing of Pure Functions

[JGreenlee]

One example test given here - simply asserting an expected output from a function of diaryHelper.

This will only allow us to test simple functions, not components

[Abby-Wheelis]

I just got a chance to test this out, and am working on adding a few more tests. This is my first time working with this testing framework, so it took me a moment to figure out. I discovered that the tests can be run by setting up the phone server (I needed to do a full re-setup to have the updated dependencies) and then typing "npm test" at the command line.

@JGreenlee can you take a look at the test I commented out and see if you think it should run? It's failing for me, but I haven't figured out why.

[JGreenlee]

No fault of the test. That function isn't working as intended!
Look at the body of the function and you see that key is never used. So the function won't work with something like MotionTypes.WALKING.

All the more reason that we need tests to find unexpected behaviors like this!

/**
 * @param motionName A string like "WALKING" or "MotionTypes.WALKING"
 * @returns A MotionType object containing the name, icon, and color of the motion type
 */
export function motionTypeOf(motionName: MotionTypeKey | `MotionTypes.${MotionTypeKey}`) {
  let key = ('' + motionName).toUpperCase();
  key = key.split(".").pop(); // if "MotionTypes.WALKING", then just take "WALKING"
  return MotionTypes[motionName] || MotionTypes.UNKNOWN;
}

[JGreenlee]

Runs correctly with fix, added commit

[JGreenlee]

@shankari How can we integrate this with Github Actions so the tests run automatically?

[shankari]

@JGreenlee you would create a new github actions workflow (.github/workflows) that runs the command. I would suggest starting with the install workflow osx-serve-install from this repo and adding on a test stage, similar to the way that the test-with-manual-install builds on osx-ubuntu-manual-install in the server code.

at this point, I think that @nataliejschultz is our GitHub actions expert since she has actually written a new workflow, although both @humbleOldSage and @MukuFlash03 have been adding tests as well.

[JGreenlee]

That seems to have worked! I think the tests ran twice though (once for the www folder, and once for the platforms/browser/www folder)
I'll see if I can ignore platforms so actions don't take longer than they need to

[shankari]

I am merging this for now, since the workflow name does not affect the addition of new tests, and we want people to write tests as they are migrating the code.

@JGreenlee please create a new workflow or rename this one in a future PR

[shankari]

In the server code, we have install and test in separate workflows.
(future fix): I am fine with having this in the same workflow (at least initially), but then we should rename the file to indicate that it is also testing.