Expose timers API

src/debounce/debounce.fork.test.ts

@@ -7,11 +7,11 @@ import {
   createEvent,
   createStore,
   sample,
-  createWatch,
-} from 'effector';
+  createWatch, createEffect,
+} from 'effector'
 import { wait, watch } from '../../test-library';
 
-import { debounce } from './index';
+import { debounce, DebounceTimerFxProps } from './index'
 
 test('debounce works in forked scope', async () => {
   const app = createDomain();
@@ -186,19 +186,23 @@ describe('edge cases', () => {
   test('does not call target twice for sample chain doubles', async () => {
     const trigger = createEvent();
 
+    const scope = fork();
     const db = debounce({ source: trigger, timeout: 100 });
 
     const listener = jest.fn();
-    db.watch(listener);
+
+    createWatch({
+      unit: db,
+      fn: listener,
+      scope,
+    })
 
     const start = createEvent();
     const secondTrigger = createEvent();
 
     sample({ clock: start, fn: () => 'one', target: [secondTrigger, trigger] });
     sample({ clock: secondTrigger, fn: () => 'two', target: [trigger] });
 
-    const scope = fork();
-
     await allSettled(start, { scope });
 
     expect(listener).toBeCalledTimes(1);
@@ -232,3 +236,44 @@ describe('edge cases', () => {
     expect(triggerListener).toBeCalledTimes(0);
   })
 });
+
+test('exposed timers api', async () => {
+  const timerFx = createEffect(({ canceller, timeout }: DebounceTimerFxProps) => {
+    const { timeoutId, rejectPromise } = canceller;
+
+    if (timeoutId) clearTimeout(timeoutId);
+    if (rejectPromise) rejectPromise();
+
+    return new Promise((resolve, reject) => {
+      canceller.timeoutId = setTimeout(resolve, timeout / 2);
+      canceller.rejectPromise = reject;
+    });
+  });
+
+  const scope = fork({
+    handlers: [
+      [debounce.timerFx, timerFx],
+    ]
+  });
+
+  const mockedFn = jest.fn();
+
+  const clock = createEvent();
+  const tick = debounce(clock, 50);
+
+  createWatch({
+    unit: tick,
+    fn: mockedFn,
+    scope,
+  });
+
+  allSettled(clock, { scope });
+
+  await wait(20);
+
+  expect(mockedFn).not.toBeCalled();
+
+  await wait(5);
+
+  expect(mockedFn).toBeCalled();
+});

src/debounce/index.ts

@@ -9,18 +9,38 @@ import {
   merge,
   UnitTargetable,
   EventAsReturnType,
+  createEffect
 } from 'effector';
 
-export function debounce<T>(
+type DebounceCanceller = { timeoutId?: NodeJS.Timeout; rejectPromise?: () => void; };
+
+export type DebounceTimerFxProps = {
+  canceller: DebounceCanceller;
+  timeout: number;
+};
+
+const timerFx = createEffect(({ canceller, timeout }: DebounceTimerFxProps) => {
+  const { timeoutId, rejectPromise } = canceller;
+
+  if (timeoutId) clearTimeout(timeoutId);
+  if (rejectPromise) rejectPromise();
+
+  return new Promise((resolve, reject) => {
+    canceller.timeoutId = setTimeout(resolve, timeout);
+    canceller.rejectPromise = reject;
+  });
+});
+
+export function _debounce<T>(
   source: Unit<T>,
   timeout: number | Store<number>,
 ): EventAsReturnType<T>;
-export function debounce<T>(_: {
+export function _debounce<T>(_: {
   source: Unit<T>;
   timeout: number | Store<number>;
   name?: string;
 }): EventAsReturnType<T>;
-export function debounce<
+export function _debounce<
   T,
   Target extends UnitTargetable<T> | UnitTargetable<void>,
 >(_: {
@@ -29,7 +49,7 @@ export function debounce<
   target: Target;
   name?: string;
 }): Target;
-export function debounce<T>(
+export function _debounce<T>(
   ...args:
     | [
         {
@@ -50,25 +70,20 @@ export function debounce<T>(
 
   const $timeout = toStoreNumber(timeout);
 
-  const saveCancel = createEvent<[NodeJS.Timeout, () => void]>();
-  const $canceller = createStore<[NodeJS.Timeout, () => void] | []>([], {
+  const $canceller = createStore<DebounceCanceller | null>(null, {
     serialize: 'ignore',
-  }).on(saveCancel, (_, payload) => payload);
+  });
 
   const tick = (target as UnitTargetable<T>) ?? createEvent();
 
-  const timerFx = attach({
+  const innerTimerFx = attach({
     name: name || `debounce(${(source as any)?.shortName || source.kind}) effect`,
-    source: $canceller,
-    effect([timeoutId, rejectPromise], timeout: number) {
-      if (timeoutId) clearTimeout(timeoutId);
-      if (rejectPromise) rejectPromise();
-      return new Promise((resolve, reject) => {
-        saveCancel([setTimeout(resolve, timeout), reject]);
-      });
-    },
+    source: $canceller as Store<DebounceCanceller>,
+    mapParams: (timeout: number, source: DebounceCanceller) => ({ canceller: source, timeout }),
+    effect: timerFx,
   });
-  $canceller.reset(timerFx.done);
+
+  $canceller.reset(innerTimerFx.done);
 
   // It's ok - nothing will ever start unless source is triggered
   const $payload = createStore<T[]>([], { serialize: 'ignore', skipVoid: false }).on(
@@ -88,15 +103,15 @@ export function debounce<T>(
         // debounce timeout should be restarted on timeout change
         $timeout,
         // debounce timeout can be restarted in later ticks
-        timerFx,
+        innerTimerFx,
       ],
       () => true,
     );
 
   const requestTick = merge([
     source,
     // debounce timeout is restarted on timeout change
-    sample({ clock: $timeout, filter: timerFx.pending }),
+    sample({ clock: $timeout, filter: innerTimerFx.pending }),
   ]);
 
   sample({
@@ -106,21 +121,33 @@ export function debounce<T>(
   });
 
   sample({
+    clock: triggerTick,
     source: $timeout,
+    fn: (timeout) => timeout,
+    target: innerTimerFx,
+  });
+
+  sample({
     clock: triggerTick,
-    target: timerFx,
+    source: $canceller,
+    fn: (canceller) => canceller ?? {},
+    target: $canceller,
   });
 
   sample({
     source: $payload,
-    clock: timerFx.done,
+    clock: innerTimerFx.done,
     fn: ([payload]) => payload,
     target: tick,
   });
 
   return tick as any;
 }
 
+export const debounce = Object.assign(_debounce, {
+  timerFx
+});
+
 function toStoreNumber(value: number | Store<number> | unknown): Store<number> {
   if (is.store(value)) return value;
   if (typeof value === 'number') {

src/debounce/readme.md

@@ -197,3 +197,32 @@ someHappened(4);
 
 // someHappened now 4
 ```
+
+### [Tests] Exposed timers API example
+
+```ts
+/**
+ * `canceller` - is object, which contains previous timeout id and previous effect promise reject
+ */
+const timerFx = createEffect(({ canceller, timeout }: DebounceTimerFxProps) => {
+  const { timeoutId, rejectPromise } = canceller;
+
+  if (timeoutId) clearTimeout(timeoutId);
+  if (rejectPromise) rejectPromise();
+
+  return new Promise((resolve, reject) => {
+    canceller.timeoutId = setTimeout(resolve, timeout);
+    canceller.rejectPromise = reject;
+  });
+});
+
+const scope = fork({
+  handlers: [[debounce.timerFx, timerFx]],
+});
+
+const clock = createEvent();
+const tick = debounce(clock, 200);
+
+// important! call from scope
+allSettled(clock, { scope });
+```

src/delay/delay.fork.test.ts

@@ -1,7 +1,14 @@
 import 'regenerator-runtime/runtime';
-import { createDomain, fork, serialize, allSettled } from 'effector';
+import {
+  createDomain,
+  fork,
+  serialize,
+  allSettled,
+  createEffect, createEvent, createWatch, UnitValue
+} from 'effector'
 
-import { delay } from './index';
+import { delay, DelayTimerFxProps } from './index'
+import { wait } from '../../test-library'
 
 test('throttle works in forked scope', async () => {
   const app = createDomain();
@@ -127,3 +134,37 @@ test('throttle do not affect original store value', async () => {
 
   expect($counter.getState()).toMatchInlineSnapshot(`0`);
 });
+
+test('exposed timers api', async () => {
+  const timerFx = createEffect<DelayTimerFxProps, UnitValue<any>>(
+    ({ payload, milliseconds }) =>
+      new Promise((resolve) => {
+        setTimeout(resolve, milliseconds / 2, payload);
+      }),
+  )
+
+  const scope = fork({
+    handlers: [[delay.timerFx, timerFx]],
+  });
+
+  const mockedFn = jest.fn();
+
+  const clock = createEvent();
+  const tick = delay(clock, 50);
+
+  createWatch({
+    unit: tick,
+    fn: mockedFn,
+    scope,
+  });
+
+  allSettled(clock, { scope });
+
+  await wait(20);
+
+  expect(mockedFn).not.toBeCalled();
+
+  await wait(5);
+
+  expect(mockedFn).toBeCalled();
+});

src/delay/index.ts

@@ -11,27 +11,36 @@ import {
   MultiTarget,
   UnitValue,
   UnitTargetable,
+  attach,
 } from 'effector';
 
 type TimeoutType<Payload> = ((payload: Payload) => number) | Store<number> | number;
+export type DelayTimerFxProps = { payload: UnitValue<any>; milliseconds: number };
 
-export function delay<Source extends Unit<any>>(
+const timerFx = createEffect<DelayTimerFxProps, UnitValue<any>>(
+  ({ payload, milliseconds }) =>
+    new Promise((resolve) => {
+      setTimeout(resolve, milliseconds, payload);
+    }),
+)
+
+export function _delay<Source extends Unit<any>>(
   source: Source,
   timeout: TimeoutType<UnitValue<Source>>,
 ): EventAsReturnType<UnitValue<Source>>;
 
-export function delay<Source extends Unit<any>, Target extends TargetType>(config: {
+export function _delay<Source extends Unit<any>, Target extends TargetType>(config: {
   source: Source;
   timeout: TimeoutType<UnitValue<Source>>;
   target: MultiTarget<Target, UnitValue<Source>>;
 }): Target;
 
-export function delay<Source extends Unit<any>>(config: {
+export function _delay<Source extends Unit<any>>(config: {
   source: Source;
   timeout: TimeoutType<UnitValue<Source>>;
 }): EventAsReturnType<UnitValue<Source>>;
 
-export function delay<
+export function _delay<
   Source extends Unit<any>,
   Target extends TargetType = TargetType,
 >(
@@ -57,15 +66,9 @@ export function delay<
 
   const ms = validateTimeout(timeout);
 
-  const timerFx = createEffect<
-    { payload: UnitValue<Source>; milliseconds: number },
-    UnitValue<Source>
-  >(
-    ({ payload, milliseconds }) =>
-      new Promise((resolve) => {
-        setTimeout(resolve, milliseconds, payload);
-      }),
-  );
+  const innerTimerFx = attach({
+    effect: timerFx
+  });
 
   sample({
     // ms can be Store<number> | number
@@ -77,14 +80,18 @@ export function delay<
       milliseconds:
         typeof milliseconds === 'function' ? milliseconds(payload) : milliseconds,
     }),
-    target: timerFx,
+    target: innerTimerFx,
   });
 
-  sample({ clock: timerFx.doneData, target: targets as UnitTargetable<any>[] });
+  sample({ clock: innerTimerFx.doneData, target: targets as UnitTargetable<any>[] });
 
   return target as any;
 }
 
+export const delay = Object.assign(_delay, {
+  timerFx
+});
+
 function validateTimeout<T>(
   timeout: number | ((_: T) => number) | Store<number> | unknown,
 ) {