From a0c72551578101895b8b09477c210ca8aecede87 Mon Sep 17 00:00:00 2001 From: Aria Minaei Date: Sun, 15 Jan 2023 22:04:27 +0100 Subject: [PATCH] Add more tests to dataverse --- packages/dataverse/src/Atom.ts | 12 +- packages/dataverse/src/Ticker.test.ts | 79 +++++ packages/dataverse/src/Ticker.ts | 2 +- packages/dataverse/src/integration.test.ts | 2 +- packages/dataverse/src/prism/newPrism.test.ts | 329 ++++++++++++++++++ packages/dataverse/src/prism/prism.test.ts | 4 +- 6 files changed, 421 insertions(+), 7 deletions(-) create mode 100644 packages/dataverse/src/Ticker.test.ts create mode 100644 packages/dataverse/src/prism/newPrism.test.ts diff --git a/packages/dataverse/src/Atom.ts b/packages/dataverse/src/Atom.ts index d7056fc..5ecb27d 100644 --- a/packages/dataverse/src/Atom.ts +++ b/packages/dataverse/src/Atom.ts @@ -150,14 +150,20 @@ export default class Atom implements IdentityPrismProvider { this._checkUpdates(this._rootScope, oldState, newState) } - get() { + get(): State { return this._currentState } + getByPointer(fn: (p: Pointer) => Pointer): S { + const pointer = fn(this.pointer) + const path = getPointerParts(pointer).path + return this._getIn(path) as S + } + /** * Gets the state of the atom at `path`. */ - getIn(path: (string | number)[]): unknown { + private _getIn(path: (string | number)[]): unknown { return path.length === 0 ? this.get() : get(this.get(), path) } @@ -230,7 +236,7 @@ export default class Atom implements IdentityPrismProvider { const subscribe = (listener: (val: unknown) => void) => this._onPathValueChange(path, listener) - const getValue = () => this.getIn(path) + const getValue = () => this._getIn(path) return prism(() => { return prism.source(subscribe, getValue) diff --git a/packages/dataverse/src/Ticker.test.ts b/packages/dataverse/src/Ticker.test.ts new file mode 100644 index 0000000..c15b2a2 --- /dev/null +++ b/packages/dataverse/src/Ticker.test.ts @@ -0,0 +1,79 @@ +import {Ticker} from '@theatre/dataverse' +import {EMPTY_TICKS_BEFORE_GOING_DORMANT} from './Ticker' + +describe(`Ticker`, () => { + test(`Usage of Ticker`, async () => { + const ticker = new Ticker() + const listener = jest.fn() + + ticker.onNextTick(listener) + + ticker.tick() + expect(listener).toHaveBeenCalledTimes(1) + + ticker.tick() + expect(listener).toHaveBeenCalledTimes(1) + }) + + test(`Tickers go dormant`, () => { + const onDormant = jest.fn() + const onActive = jest.fn() + const ticker = new Ticker({onDormant, onActive}) + expect(ticker.dormant).toBe(true) + + const listener = jest.fn() + ticker.onNextTick(listener) + expect(ticker.dormant).toBe(false) + expect(onActive).toHaveBeenCalledTimes(1) + + ticker.tick() + expect(listener).toHaveBeenCalledTimes(1) + + // at this point, the ticker is active, but after a few ticks, it should go dormant + for (let i = 0; i < EMPTY_TICKS_BEFORE_GOING_DORMANT; i++) { + ticker.tick() + if (i < EMPTY_TICKS_BEFORE_GOING_DORMANT - 1) { + expect(ticker.dormant).toBe(false) + expect(onDormant).toHaveBeenCalledTimes(0) + } + } + + expect(ticker.dormant).toBe(true) + expect(onDormant).toHaveBeenCalledTimes(1) + + // after going dormant, it should stay dormant + ticker.tick() + expect(ticker.dormant).toBe(true) + expect(onDormant).toHaveBeenCalledTimes(1) + + // but if we schedule a callback, it should go active again + ticker.onNextTick(listener) + expect(ticker.dormant).toBe(false) + expect(onActive).toHaveBeenCalledTimes(2) + }) + + test(`Ticker.onThisOrNextTick()`, () => { + const ticker = new Ticker() + const mainListener = jest.fn(() => { + ticker.onNextTick(thisWillBeCalledOnTheNextTick) + ticker.onThisOrNextTick(thisWillBeCalledOnTheSameTick) + }) + const thisWillBeCalledOnTheSameTick = jest.fn() + const thisWillBeCalledOnTheNextTick = jest.fn() + + ticker.onThisOrNextTick(mainListener) + expect(mainListener).toHaveBeenCalledTimes(0) + expect(thisWillBeCalledOnTheSameTick).toHaveBeenCalledTimes(0) + expect(thisWillBeCalledOnTheNextTick).toHaveBeenCalledTimes(0) + + ticker.tick() + expect(mainListener).toHaveBeenCalledTimes(1) + expect(thisWillBeCalledOnTheSameTick).toHaveBeenCalledTimes(1) + expect(thisWillBeCalledOnTheNextTick).toHaveBeenCalledTimes(0) + + ticker.tick() + expect(mainListener).toHaveBeenCalledTimes(1) + expect(thisWillBeCalledOnTheSameTick).toHaveBeenCalledTimes(1) + expect(thisWillBeCalledOnTheNextTick).toHaveBeenCalledTimes(1) + }) +}) diff --git a/packages/dataverse/src/Ticker.ts b/packages/dataverse/src/Ticker.ts index f0032c5..89462db 100644 --- a/packages/dataverse/src/Ticker.ts +++ b/packages/dataverse/src/Ticker.ts @@ -6,7 +6,7 @@ type ICallback = (t: number) => void * * Perhaps counting ticks vs. time is not the best way to do this. But it's a start. */ -const EMPTY_TICKS_BEFORE_GOING_DORMANT = 60 /*fps*/ * 3 /*seconds*/ // on a 60fps screen, 3 seconds should pass before the ticker goes dormant +export const EMPTY_TICKS_BEFORE_GOING_DORMANT = 60 /*fps*/ * 3 /*seconds*/ // on a 60fps screen, 3 seconds should pass before the ticker goes dormant /** * The Ticker class helps schedule callbacks. Scheduled callbacks are executed per tick. Ticks can be triggered by an diff --git a/packages/dataverse/src/integration.test.ts b/packages/dataverse/src/integration.test.ts index 6a23b9e..09fa695 100644 --- a/packages/dataverse/src/integration.test.ts +++ b/packages/dataverse/src/integration.test.ts @@ -5,7 +5,7 @@ import Atom, {val} from './Atom' import prism from './prism/prism' import Ticker from './Ticker' -describe(`v2 atom`, () => { +describe(`integration`, () => { describe(`identity pointers`, () => { it(`should work`, () => { const data = {foo: 'hi', bar: 0} diff --git a/packages/dataverse/src/prism/newPrism.test.ts b/packages/dataverse/src/prism/newPrism.test.ts new file mode 100644 index 0000000..d2fff18 --- /dev/null +++ b/packages/dataverse/src/prism/newPrism.test.ts @@ -0,0 +1,329 @@ +import {prism} from '@theatre/dataverse' + +describe(`prism()`, () => { + // these tests are going will act as a guide on how to use prisms. + + // prisms are a way to create a value that depends on other values. + // prisms can be hot or cold, they have dependencies and dependents, and hot prisms can be stale or fresh. + + // let's start with a simple example: + test(`using a pretty useless prism`, async () => { + // each prism has a calculate function that it runs to calculate its value. let's make a simple function that just returns 1 + const calculate = jest.fn(() => 1) + + // now we can make a prism out of it + const pr = prism(calculate) + + // now, this prism is pretty useless. it doesn't depend on anything, and it doesn't have any dependents. + // but we can already illustrate some of the concepts that are important to understand prisms. + + // `calculate` won't be called until it's needed + expect(calculate).not.toHaveBeenCalled() + + // we can get the value of the prism, which will be what `calculate` returned + expect(pr.getValue()).toBe(1) + + // now the calculate function will have be called + expect(calculate).toHaveBeenCalledTimes(1) + + // now, you might expect that if we call `getValue()` again, the calculate function won't be called again. + // but that's not the case. the calculate function will be called again, because the prism is cold. + // we'll talk about cold/hot in a bit, but let's just say that cold prisms are calculated every time they're read. + + pr.getValue() + expect(calculate).toHaveBeenCalledTimes(2) + + // we can even check whether a prism is hot or cold. Ours is cold. + expect(pr.isHot).toBe(false) + + // we'll get to hot prisms soon, but let's talk about dependencies and dependents first. + }) + + // prisms can depend on other prisms. let's make a prism that depends on another prism. + test(`prisms can depend on other prisms`, async () => { + const calculateA = jest.fn(() => 1) + const a = prism(calculateA) + + const calculateATimesTwo = jest.fn(() => a.getValue() * 2) + const aTimesTwo = prism(calculateATimesTwo) + + // clear the count of mocks + function clearMocks() { + calculateA.mockClear() + calculateATimesTwo.mockClear() + } + + // now, `aTimesTwo` depends on `a`. + // In our parlance, `aTimesTwo` is a dependent of `a`, and `a` is a dependency of `aTimesTwo`. + + // now if we read the value of `aTimesTwo`, it will call `calculateATimesTwo`, which will call `calculateA`: + expect(aTimesTwo.getValue()).toBe(2) + expect(calculateA).toHaveBeenCalledTimes(1) + expect(calculateATimesTwo).toHaveBeenCalledTimes(1) + + clearMocks() + + // and like we saw in the previous test, if we read the value of `aTimesTwo` again, it will call both of our calculate functions again: + aTimesTwo.getValue() + expect(calculateATimesTwo).toHaveBeenCalledTimes(1) + expect(calculateA).toHaveBeenCalledTimes(1) + + clearMocks() + + // but if we read the value of `a`, it won't call `calculateATimesTwo`: + a.getValue() + expect(calculateATimesTwo).toHaveBeenCalledTimes(0) + expect(calculateA).toHaveBeenCalledTimes(1) + + clearMocks() + + // now let's see what happens if we make our prism hot. + + // one way to do this, is to add an `onStale` listener to our prism. + const onStale = jest.fn() + const unsubscribe = aTimesTwo.onStale(onStale) + + // as soon as we do this, the prism will become hot. + expect(aTimesTwo.isHot).toBe(true) + + // and so will its dependencies: + expect(a.isHot).toBe(true) + + // so let's see what happens when we read the value of `aTimesTwo` again: + aTimesTwo.getValue() + // `calculateATimesTwo` will be called again, + expect(calculateATimesTwo).toHaveBeenCalledTimes(1) + // and so will `calculateA`, + expect(calculateA).toHaveBeenCalledTimes(1) + + clearMocks() + + // but if we read `aTimesTwo` again, none of the calculate functions will be called again. + aTimesTwo.getValue() + expect(calculateATimesTwo).toHaveBeenCalledTimes(0) + expect(calculateA).toHaveBeenCalledTimes(0) + + clearMocks() + + // this behavior propogates up the dependency chain, so if we read `a` again, `calculateA` won't be called again, + // because its value is already fresh. + a.getValue() + expect(calculateA).toHaveBeenCalledTimes(0) + + clearMocks() + + // at this point, since none of our prisms depend on a prism whose value will change, they'll remain + // fresh forever. + a.getValue() + aTimesTwo.getValue() + a.getValue() + aTimesTwo.getValue() + + expect(calculateATimesTwo).toHaveBeenCalledTimes(0) + expect(calculateA).toHaveBeenCalledTimes(0) + + clearMocks() + + // but as soon as we unsubscribe from our `onStale()` listener, the prisms will become cold again. + unsubscribe() + expect(aTimesTwo.isHot).toBe(false) + expect(a.isHot).toBe(false) + + // and they'll return back to their cold behavior. + aTimesTwo.getValue() + expect(calculateATimesTwo).toHaveBeenCalledTimes(1) + expect(calculateA).toHaveBeenCalledTimes(1) + + clearMocks() + + aTimesTwo.getValue() + expect(calculateATimesTwo).toHaveBeenCalledTimes(1) + expect(calculateA).toHaveBeenCalledTimes(1) + + clearMocks() + + // now, one more thing before we move on. What will if we make `a` hot, but not `aTimesTwo`? + // let's try it out. + const unsubcribeFromAOnStale = a.onStale(() => {}) + // a will go hot + expect(a.isHot).toBe(true) + // but aTimesTwo will stay cold + expect(aTimesTwo.isHot).toBe(false) + + // now let's read the value of `a` + a.getValue() + + // `calculateA` will be called + expect(calculateA).toHaveBeenCalledTimes(1) + // and obviously `calculateATimesTwo` won't be called + expect(calculateATimesTwo).toHaveBeenCalledTimes(0) + + clearMocks() + + // and if we re-read the value of `a`, `calculateA` won't be called again, becuase `a` is hot and its value is fresh. + a.getValue() + expect(calculateA).toHaveBeenCalledTimes(0) + + clearMocks() + + // but if we read the value of `aTimesTwo`, `calculateATimesTwo` will be called, because `aTimesTwo` is cold. + aTimesTwo.getValue() + expect(calculateATimesTwo).toHaveBeenCalledTimes(1) + // yet `calculateA` won't be called, because `a` is hot and its value is fresh. + expect(calculateA).toHaveBeenCalledTimes(0) + + clearMocks() + + // in conclusion, if we make a prism hot, it'll make its dependencies hot too. + // if we read the value of a cold prism, it'll call its calculate function, which will + // call the calculate functions of its dependencies, and so on. + // but if we read the value of a hot prism, it'll only call its calculate function if its value is stale. + + // le'ts wrap up this part by unsubscribing from `a`'s `onStale` listener to not have any lingering listeners. + unsubcribeFromAOnStale() + }) + + // so far, our prisms have not depended on any changing values, so in turn, _their_ values have never changed either. + // but what if we want to create a prism that depends on a changing value? + // we call those values "sources", and we can create them using the `prism.source()` hook: + test('prism.source()', () => { + // let's say we want to create a prism that depends on this value: + let value = 0 + + { + // the _wrong_ way to do this, is to create a prism that directly reads this value + const p = prism(() => value) + + // this will actually work if the prism is cold: + expect(p.getValue()).toBe(0) + value = 1 + expect(p.getValue()).toBe(1) + + // but if we make the prism hot, it'll never update its value, because it's not subscribed to any sources. + const unsubscribe = p.onStale(() => {}) + expect(p.isHot).toBe(true) + // on first read, it'll give us the current value of `value`, which is 1. + expect(p.getValue()).toBe(1) + // but if we change `value` again, the prism won't know + value = 2 + expect(p.getValue()).toBe(1) + // and so it'll keep returning the old value. + expect(p.getValue()).toBe(1) + + unsubscribe() + } + + // so, the _right_ way to do this, is to use the `source` hook: + { + // the source hook requires a `listen` function, and a `get` function. + // let's skip the `listen` function for now, and just focus on the `getValue` function. + const listen = jest.fn(() => () => {}) + // the `getValue` function should return the current value of the source. + const get = jest.fn(() => value) + + const p = prism(() => { + return prism.source(listen, get) * 2 + }) + + value = 1 + + // our prism is cold right now. let's see what happens when we read its value. + expect(p.getValue()).toBe(2) + // `get` will be called once, because we're reading the value of the source for the first time. + expect(get).toHaveBeenCalledTimes(1) + // and `listen` won't be called at all + expect(listen).toHaveBeenCalledTimes(0) + + get.mockClear() + + // now let's make the prism hot + const unsubscribe = p.onStale(() => {}) + expect(p.isHot).toBe(true) + expect(p.getValue()).toBe(2) + // `get` will be called again, because we're reading the value of the source for the second time. + expect(get).toHaveBeenCalledTimes(1) + // and `listen` will be called once, because our prism wants to be notified when the source changes. + expect(listen).toHaveBeenCalledTimes(1) + + get.mockClear() + listen.mockClear() + + // now, since our `listen` function is a mock, it won't actually do anything, + // so the prism still won't know when the source changes. + value = 2 + expect(p.getValue()).toBe(2) + // `get` won't be called again, because the source hasn't changed. + expect(get).toHaveBeenCalledTimes(0) + + unsubscribe() + } + + { + let value = 0 + // now let's implement an actual `listen` function. + + // first, we need to keep track of all the listeners that our source wil have + const listeners = new Set<(val: number) => void>() + + // the `listen` function should return an stop function. + // the stop function should stop listening to the source. + const listen = jest.fn((fn) => { + listeners.add(fn) + + return function stop() { + listeners.delete(fn) + } + }) + + const get = jest.fn(() => value) + + // and now we need to define a function that will notify all the listeners that the source has changed. + const set = (newValue: number) => { + if (newValue !== value) { + value = newValue + listeners.forEach((fn) => fn(value)) + } + } + + // don't worry, there are helpers for this in dataverse. but for now, we'll implement + // it manually to understand how it works. + + // now let's create a prism that depends on our source. + const p = prism(() => { + return prism.source(listen, get) * 2 + }) + + // let's make the prism hot + const staleListener = jest.fn() + const unsubscribe = p.onStale(staleListener) + expect(p.isHot).toBe(true) + + // and let's read its value + expect(p.getValue()).toBe(0) + // `get` will be called once, because we're reading the value of the source for the first time. + expect(get).toHaveBeenCalledTimes(1) + // and `listen` will be called once, because our prism wants to be notified when the source changes. + expect(listen).toHaveBeenCalledTimes(1) + + get.mockClear() + listen.mockClear() + + // now let's change the value of the source + set(1) + + // this time, our prism will know that the source has changed, and it'll update its value. + expect(p.getValue()).toBe(2) + + // and that's how we can create a prism that depends on a changing value. + + unsubscribe() + } + }) + + // in practice, we'll almost never need to use the `source` hook directly, + // and we'll never need to provide our own `listen` and `get` functions. + // instead, we'll use `Atom`s, which are sources that are already implemented for us. + describe(`Basics of Atoms`, () => { + // TODO + }) +}) diff --git a/packages/dataverse/src/prism/prism.test.ts b/packages/dataverse/src/prism/prism.test.ts index e86a76e..957cdb1 100644 --- a/packages/dataverse/src/prism/prism.test.ts +++ b/packages/dataverse/src/prism/prism.test.ts @@ -36,9 +36,9 @@ describe('prism', () => { return bD.getValue() }) expect(cD.getValue()).toEqual(2) - const untap = cD.keepHot() + const unsubscribe = cD.keepHot() expect((cD as $IntentionalAny)._state.handle._dependencies.size).toEqual(1) - untap() + unsubscribe() }) describe('prism.ref()', () => {