Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
eater
Search
Yosuke Furukawa
PRO
April 26, 2016
Programming
2
1.3k
eater
node 学園付属小学校の2回目で話した eater の話です。
Yosuke Furukawa
PRO
April 26, 2016
Tweet
Share
More Decks by Yosuke Furukawa
See All by Yosuke Furukawa
Node.js, Deno, Bun 最新動向とその所感について
yosuke_furukawa
PRO
9
3.7k
Welcome JSConf.jp 2024
yosuke_furukawa
PRO
1
4.1k
tc39 x jsconf.jp Panel Discussion 2024
yosuke_furukawa
PRO
0
230
Removing Corepack
yosuke_furukawa
PRO
9
1.6k
JavaScript Runtime とはなにか
yosuke_furukawa
PRO
15
2.8k
Strip Types と Storage
yosuke_furukawa
PRO
4
410
Module Harmony について
yosuke_furukawa
PRO
3
1.7k
LTのやり方
yosuke_furukawa
PRO
16
2.6k
AppRouter Panel Talk
yosuke_furukawa
PRO
3
810
Other Decks in Programming
See All in Programming
A2A プロトコルを試してみる
azukiazusa1
2
1.3k
AIと”コードの評価関数”を共有する / Share the "code evaluation function" with AI
euglena1215
1
100
Systèmes distribués, pour le meilleur et pour le pire - BreizhCamp 2025 - Conférence
slecache
0
120
Azure AI Foundryではじめてのマルチエージェントワークフロー
seosoft
0
150
Flutterで備える!Accessibility Nutrition Labels完全ガイド
yuukiw00w
0
140
たった 1 枚の PHP ファイルで実装する MCP サーバ / MCP Server with Vanilla PHP
okashoi
1
220
WindowInsetsだってテストしたい
ryunen344
1
230
ペアプロ × 生成AI 現場での実践と課題について / generative-ai-in-pair-programming
codmoninc
1
4.3k
Discover Metal 4
rei315
2
110
Is Xcode slowly dying out in 2025?
uetyo
1
250
deno-redisの紹介とJSRパッケージの運用について (toranoana.deno #21)
uki00a
0
180
「Cursor/Devin全社導入の理想と現実」のその後
saitoryc
0
700
Featured
See All Featured
The Psychology of Web Performance [Beyond Tellerrand 2023]
tammyeverts
48
2.9k
[RailsConf 2023] Rails as a piece of cake
palkan
55
5.6k
Distributed Sagas: A Protocol for Coordinating Microservices
caitiem20
331
22k
Being A Developer After 40
akosma
90
590k
Design and Strategy: How to Deal with People Who Don’t "Get" Design
morganepeng
130
19k
Why Our Code Smells
bkeepers
PRO
337
57k
Why You Should Never Use an ORM
jnunemaker
PRO
58
9.4k
Building a Scalable Design System with Sketch
lauravandoore
462
33k
Fight the Zombie Pattern Library - RWD Summit 2016
marcelosomers
233
17k
VelocityConf: Rendering Performance Case Studies
addyosmani
331
24k
Sharpening the Axe: The Primacy of Toolmaking
bcantrill
44
2.4k
Optimising Largest Contentful Paint
csswizardry
37
3.3k
Transcript
Eater @yosuke_furukawa
@yosuke_furukawa
Hello, Noders. This is Full-time Papa committer
None
child_process.spawn()
None
Node Quiz
Quiz: child_process API ͷԼهͷ ҧ͍ԿͰ͠ΐ͏ 1. exec 2. spawn 3.
fork
A: spawn ͕Ұ൪ϩʔϨϕϧ exec/fork spawn ͷ wrapper
A: exec callback Ͱड͚Δɺ fork JavaScript ͷίʔυ Λ
Node.js ͱͯ͠࠶࣮ߦ͢Δ
child_process.spawn const spawn = require('child_process').spawn; const ls = spawn('ls', [‘-al']);
ls.stdout.on('data', (data) => { console.log(data); }); ls.stderr.on('data', (data) => { console.log(data); }); ls.on('exit', (code) => { if (code !== 0) console.error(`Error occurred`); });
child_process.exec const exec = require('child_process').exec; exec(‘ls -al‘, (err, stdout, stderr)
=> { console.log(`${stdout}`); console.error(`${stderr}`); if (error !== null) { console.error(`Error occurred`); } });
child_process.fork const fork = require('child_process').fork; const ls = fork(‘ls.js’); ls.stdout.on('data',
(data) => { console.log(data); }); ls.stderr.on('data', (data) => { console.log(data); }); ls.on('exit', (code) => { if (code !== 0) console.error(`Error occurred`); });
spawn > exec ͜ͷॱͰ simple exec > spawn ͜ͷॱͰ easy
spawn > fork ͜ͷॱͰ simple fork > spawn ͜ͷॱͰ easy
Easy / Simple ͷҧ͍
None
Simple !== Easy
Simple is “୯७” ٬؍తɺҰͭͷࣄ͔͠͠ͳ͍
Easy is “؆୯” ओ؍తɺ”୭͔”ʹͱͬͯ؆୯ “୭ʹͱͬͯ؆୯” ଘࡏ͠ͳ͍
ॳ৺ऀ͕ؕΓ͕ͪͳࣄɿ Easy ͷݴ༿ʹὃ͞Ε͕ͪ ୭ʹͱͬͯEasy ͳΜͯ͋Γ ͑ͳ͍
ॳ৺ऀ͕ؕΓ͕ͪͳࣄɿ Simple ͱ Easy Λࠞಉ͍ͯ͠ Δʹࠔ͞Ε͕ͪ
Eater
Eater is *Ea*sy *t*est runn*er*
Eater has one simple rule If test file outputs `stderr`
message, the test failed.
Easy => ୭ʹͱͬͯʁ `node` ͔͠Βͳ͍Α͏ͳਓ mocha/jestͷࡉ͔͍ߏจΛ֮ ͑ͯͳͯ͘ɺnode ίϚϯυ ͰεΫϦϓτͱ࣮ͯ͠ߦ͢Δ ͚ͩͰΠφϑͳਓ
Eaterͷtest script `node` command Ͱ࣮ߦͰ͖Δ
Easy => ୭ʹͱͬͯʁ mock/spyΛଟ༻͢Δ͚Ͳɺ mock/spyͷ։์࿙ΕΛΕ ͕ͪͳਓʹͱͬͯ
EaterͷtestҰͭҰ͕ͭผϓ ϩηεͰ࣮ߦ͞ΕΔ
mockΛ։์͠ͳͯ͘OK // you don’t need to fix mock/spy console.log =>
(message) { assert(message.match(/Foo Bar/)); }; const mockDate = new Date(2016, 3, 9); Date.now = () => { return mockDate.valueOf(); }; process.exit => (exitcode) { assert(exitcode === 1); };
͔͠ϓϩηείΞͰ ಄ଧͪʹͳΔ eater ——procs 4 ※procs optionͰՄม
Eater DEMO https://github.com/yosuke- furukawa/eater-demo
Happy Eater https://github.com/yosuke- furukawa/eater