Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Sign up for free
Menu
Search
Features
All features
Private URLs
Password Protection
Custom URLS
Scheduled publishing
Remove Branding
Restrict embedding
Deck Collections
Notes
Explore
Featured decks
Featured speakers
Programming
Technology
Storyboards
Pricing
Search
Sign in
Sign up for free
eater
Search
Yosuke Furukawa
PRO
April 26, 2016
Programming
1.4k
2
Share
Embed
Copy iframe code
Copy JS code
Copy link
Start on current slide
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
More Decks by Yosuke Furukawa
See All by Yosuke Furukawa
Webの地図
yosuke_furukawa
PRO
3
2.4k
XHTMLが残したもの
yosuke_furukawa
PRO
2
460
jsmini JavaScript Engine を作ってみた話
yosuke_furukawa
PRO
0
390
デザインシステムが必須の時代に
yosuke_furukawa
PRO
2
280
Node.js, Deno, Bun 最新動向とその所感について
yosuke_furukawa
PRO
10
5.3k
Welcome JSConf.jp 2024
yosuke_furukawa
PRO
1
4.8k
tc39 x jsconf.jp Panel Discussion 2024
yosuke_furukawa
PRO
0
360
Removing Corepack
yosuke_furukawa
PRO
9
2k
JavaScript Runtime とはなにか
yosuke_furukawa
PRO
15
3.2k
Other Decks in Programming
See All in Programming
Family mrubyの進捗
kishima
1
100
Building an Out-of-Order CPU
latte72
1
730
スマート反転とウェブアクセシビリティ
camiha
0
160
Go を使い始めて 2 ヶ月の学び / My first two months with Go
contour_gara
0
420
数年滞っていたダークモード対応をおよそ2週間で完了させる
chigichan24
0
690
PyO3 で既存 Python 評価器を Rust core 化する ー wasm-bindgen でブラウザにも配るための設計
kdash
1
560
週末にAI-DLCを本気で回したら$1,600溶けた
hbashimizu
0
130
不幸な GC
chencmd
0
890
What We Talk About When We Talk About XP
m_seki
2
410
PHPプロジェクトの結合バランスを可視化する #php_night
kajitack
0
230
GKE で Pod の見方を変えたら、スケールアウト時の挙動を真に捉えられた話
stkk
0
100
AIの中の人になってみる
htkym
0
170
Featured
See All Featured
What Being in a Rock Band Can Teach Us About Real World SEO
427marketing
0
1.1k
The agentic SEO stack - context over prompts
schlessera
0
910
GraphQLの誤解/rethinking-graphql
sonatard
75
12k
The Illustrated Children's Guide to Kubernetes
chrisshort
51
53k
Bioeconomy Workshop: Dr. Julius Ecuru, Opportunities for a Bioeconomy in West Africa
akademiya2063
PRO
1
340
A brief & incomplete history of UX Design for the World Wide Web: 1989–2019
jct
2
500
How to build an LLM SEO readiness audit: a practical framework
nmsamuel
1
890
XXLCSS - How to scale CSS and keep your sanity
sugarenia
249
1.3M
技術選定の審美眼(2025年版) / Understanding the Spiral of Technologies 2025 edition
twada
PRO
120
120k
How People are Using Generative and Agentic AI to Supercharge Their Products, Projects, Services and Value Streams Today
helenjbeal
1
310
Connecting the Dots Between Site Speed, User Experience & Your Business [WebExpo 2025]
tammyeverts
11
1k
The SEO Collaboration Effect
kristinabergwall1
1
550
Transcript
Eater @yosuke_furukawa
@yosuke_furukawa
Hello, Noders. This is Full-time Papa committer
None
child_process.spawn()
None
Node Quiz
Quiz: child_process API ͷԼهͷ ҧ͍ԿͰ͠ΐ͏ 1. exec 2. spawn 3.
fork
A: spawn ͕Ұ൪ϩʔϨϕϧ exec/fork spawn ͷ wrapper
A: exec callback Ͱड͚Δɺ fork JavaScript ͷίʔυ Λ
Node.js ͱͯ͠࠶࣮ߦ͢Δ
child_process.spawn const spawn = require('child_process').spawn; const ls = spawn('ls', [‘-al']);
ls.stdout.on('data', (data) => { console.log(data); }); ls.stderr.on('data', (data) => { console.log(data); }); ls.on('exit', (code) => { if (code !== 0) console.error(`Error occurred`); });
child_process.exec const exec = require('child_process').exec; exec(‘ls -al‘, (err, stdout, stderr)
=> { console.log(`${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