test: test for scheduler

jest.config.js

@@ -0,0 +1,12 @@
+module.exports = {
+  preset: 'ts-jest',
+  coverageDirectory: 'coverage',
+  coverageReporters: ['html', 'lcov', 'text'],
+  collectCoverageFrom: ['packages/*/src/**/*.ts'],
+  moduleFileExtensions: ['ts', 'js', 'json'],
+  moduleNameMapper: {
+    '^@vue/(.*?)$': '<rootDir>/packages/$1/src'
+  },
+  rootDir: __dirname,
+  testMatch: ['<rootDir>/packages/**/__tests__/**/*spec.(t|j)s']
+}

package.json

@@ -23,10 +23,12 @@
     ]
   },
   "devDependencies": {
+    "@types/jest": "^23.3.2",
     "chalk": "^2.4.1",
     "dts-bundle": "^0.7.3",
     "execa": "^1.0.0",
     "fs-extra": "^7.0.0",
+    "jest": "^23.6.0",
     "lerna": "^3.4.0",
     "lint-staged": "^7.2.2",
     "minimist": "^1.2.0",
@@ -36,6 +38,7 @@
     "rollup-plugin-replace": "^2.0.0",
     "rollup-plugin-terser": "^2.0.2",
     "rollup-plugin-typescript2": "^0.17.0",
+    "ts-jest": "^23.10.0",
     "typescript": "^3.0.3",
     "yorkie": "^2.0.0"
   }

packages/scheduler/__tests__/scheduler.spec.ts

@@ -0,0 +1,78 @@
+import { queueJob, nextTick } from '../src/index'
+
+test('queueJob', async () => {
+  const calls: any = []
+  const job1 = () => {
+    calls.push('job1')
+  }
+  const job2 = () => {
+    calls.push('job2')
+  }
+  queueJob(job1)
+  queueJob(job2)
+  expect(calls).toEqual([])
+  await nextTick()
+  expect(calls).toEqual(['job1', 'job2'])
+})
+
+test('queueJob while already flushing', async () => {
+  const calls: any = []
+  const job1 = () => {
+    calls.push('job1')
+    // job1 queues job2
+    queueJob(job2)
+    // should be called sync
+    expect(calls).toEqual(['job1', 'job2'])
+  }
+  const job2 = () => {
+    calls.push('job2')
+  }
+  queueJob(job1)
+  expect(calls).toEqual([])
+  await nextTick()
+  expect(calls).toEqual(['job1', 'job2'])
+})
+
+test('queueJob w/ postFlushCb', async () => {
+  const calls: any = []
+  const job1 = () => {
+    calls.push('job1')
+  }
+  const job2 = () => {
+    calls.push('job2')
+  }
+  const cb1 = () => {
+    calls.push('cb1')
+  }
+  const cb2 = () => {
+    calls.push('cb2')
+  }
+  queueJob(job1, cb1)
+  queueJob(job2, cb2)
+  await nextTick()
+  expect(calls).toEqual(['job1', 'job2', 'cb1', 'cb2'])
+})
+
+test('queueJob w/ postFlushCb while flushing', async () => {
+  const calls: any = []
+  const job1 = () => {
+    calls.push('job1')
+    // job1 queues job2
+    queueJob(job2, cb2)
+    // should be called sync
+    expect(calls).toEqual(['job1', 'job2'])
+  }
+  const job2 = () => {
+    calls.push('job2')
+  }
+  const cb1 = () => {
+    calls.push('cb1')
+  }
+  const cb2 = () => {
+    calls.push('cb2')
+  }
+  queueJob(job1, cb1)
+  expect(calls).toEqual([])
+  await nextTick()
+  expect(calls).toEqual(['job1', 'job2', 'cb1', 'cb2'])
+})

packages/scheduler/src/index.ts

@@ -1,10 +1,11 @@
 const queue: Array<() => void> = []
 const postFlushCbs: Array<() => void> = []
 const p = Promise.resolve()
+
 let flushing = false
 
-export function nextTick(fn: () => void) {
+export function nextTick(fn?: () => void): Promise<void> {
-  p.then(fn)
+  return p.then(fn)
 }
 
 export function queueJob(job: () => void, postFlushCb?: () => void) {