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eater
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Yosuke Furukawa
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April 26, 2016
Programming
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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
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April 26, 2016
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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