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
Walking through the source code of an OSS libra...
Search
kkeeth
May 21, 2022
Programming
0
200
Walking through the source code of an OSS library(ESLint)
kkeeth
May 21, 2022
Tweet
Share
More Decks by kkeeth
See All by kkeeth
Programming to play with p5.js
clown0082
0
22
とある EM の初めての育休からの学び
clown0082
1
3.9k
The history of Javascript frameworks: changes in front-end design philosophy
clown0082
2
180
Visually experience the beauty of mathematics with p5.js
clown0082
1
3k
Rediscover the joy of coding with Creative Coding
clown0082
0
1.6k
全員が意思決定する会社で開発者体験や生産性を見る大変さについて
clown0082
0
620
JavaScript × Mathematics go to Digital Art
clown0082
1
390
In-house study group at YUMEMI
clown0082
0
210
Playing Ionic Logo by p5.js
clown0082
0
280
Other Decks in Programming
See All in Programming
[Codecon - 2025] Como não odiar seus testes
camilacampos
0
100
React 使いじゃなくても知っておきたい教養としての React
oukayuka
11
1.3k
リッチエディターを安全に開発・運用するために
unachang113
1
270
AIのメモリー
watany
11
1k
Understanding Kotlin Multiplatform
l2hyunwoo
0
230
状態遷移図を書こう / Sequence Chart vs State Diagram
orgachem
PRO
3
290
効率的な開発手段として VRTを活用する
ishkawa
1
180
MCPを使ってイベントソーシングのAIコーディングを効率化する / Streamlining Event Sourcing AI Coding with MCP
tomohisa
0
190
20250708_JAWS_opscdk
takuyay0ne
2
150
フロントエンドのパフォーマンスチューニング
koukimiura
6
2.3k
SQLアンチパターン第2版 データベースプログラミングで陥りがちな失敗とその対策 / Intro to SQL Antipatterns 2nd
twada
PRO
34
10k
AI Agent 時代のソフトウェア開発を支える AWS Cloud Development Kit (CDK)
konokenj
6
1k
Featured
See All Featured
Side Projects
sachag
455
43k
Typedesign – Prime Four
hannesfritz
42
2.7k
How to Ace a Technical Interview
jacobian
278
23k
For a Future-Friendly Web
brad_frost
179
9.8k
StorybookのUI Testing Handbookを読んだ
zakiyama
30
5.9k
How GitHub (no longer) Works
holman
314
140k
Thoughts on Productivity
jonyablonski
69
4.8k
Cheating the UX When There Is Nothing More to Optimize - PixelPioneers
stephaniewalter
283
13k
Why You Should Never Use an ORM
jnunemaker
PRO
58
9.5k
Intergalactic Javascript Robots from Outer Space
tanoku
271
27k
YesSQL, Process and Tooling at Scale
rocio
173
14k
GitHub's CSS Performance
jonrohan
1031
460k
Transcript
Walking through the source code of an OSS library(ESLint)
'SPOUFOE&OHJOFFS-5 #FFS#BTI @kkeeth @kuwahara_jsri @kkeeth
Who am I const my_info = { Name: ‘Kuwahara KEETH
Kiyohito’, Company: ‘Yumemi Inc’, Position: ‘Servant Leader/Board’, Skills: ‘Riot.js/Next.js/Chit-chat’, }
Published
OQNKTDPNdLLFFUI
🙇 Sorry … 🙇 This slide is written in English.
However, I am still learning English, and there may be some inappropriate expressions. Plz feedback for me called “Masakari” about my talk!!
Let’s start 😆
one day in development 💁
*NDPODFSOFEBCPVUUIFCFIBWJPS PGUIJTEFQFOEFOUMJCSBSZ🤔 *TOUUIBUBIVSEMFUPCFHJOXJUI $BOZPVSFBMMZSFBEJU me my “inner voice” -FUTSFBEUIFDPEFPGUIJTMJCSBSZ
me
:FT CVU*EPOUVOEFSTUBOEXIBU UIJTMJCSBSZJTEPJOHBOE .BZCFZPVEPOUIBWFUIFUJNF *TUIBUFTTFOUJBMMZXIBUZPVXBOUUP TPMWF me my “inner
voice” *UEFQFOETPOUIFUIJOH CVU JOUFSJNTVQQPSUDBOCFBMJBCJMJUZ MBUFSPO me
#VUFWFOJGZPVVOEFSTUBOEUIF TPVSDFDPEF XIBUEPZPVEPXJUI JU my “inner voice” *GJUTBCVH JUTCFTUUPDSFBUFBO JTTVFPS13
me 8IFOEPZPVUIJOLUIBUXJMMCF SFTPMWFE %PZPVUIJOLJUXJMMCF EPOFPOUJNF my “inner voice”
*GOPU UIFXPSTUUIBUDBOIBQQFOJT UIBUXFGPSLUIFSFQPTJUPSZBOE MPBEUIFDIBOHFT 8IPJTHPJOHUPNBJOUBJOJU 8IBUTUIFDPTU me my “inner
voice” )NNN*HVFTTTP0LBZ MFUT KVTUBTTVNFUIBUTUIFEFTJHOJUT TVQQPTFEUPCF😅 me
*GOPU UIFXPSTUUIBUDBOIBQQFOJT UIBUXFGPSLUIFSFQPTJUPSZBOE MPBEUIFDIBOHFT 8IPJTHPJOHUPNBJOUBJOJU 8IBUTUIFDPTU me my “inner
voice” )NNN*HVFTTTP0LBZ MFUT KVTUBTTVNFUIBUTUIFEFTJHOJUT TVQQPTFEUPCF😅 me none of your business ʘ(^o^)ʗ
I feel like I could learn more from reading codes
😆
Then, let's read the source code of ESLint!
*NBHFCZIUUQTFTMJOUPSH
Basically, we start from the module written in the main
of package.json💁
Next, let’s look at “bin” dir.
Only 3 helper functions and an executable function here💁
None
Next, let’s look at “lib/cli.js” fi le.
None
“cli.js” depends on “ESLint” module “ESLint” module depends on “CLIEngine”
module
I found out later that...
There exists a dependency map💁 *NBHFCZIUUQTHJUIVCDPNFTMJOUFTMJOUCMPCNBJOEPDTTSDEFWFMPQFSHVJEFBSDIJUFDUVSFEFQFOEFODZTWH
Knowledge 1: Overall design
Unified format for writing each module📝
Uni fi ed format for writing each module
Uni fi ed format for writing each module
util objects rich in methods📝
w /PEFKTlVUJMzPCKFDU w MJCSVMFTVUJMTBTUVUJMT w MJCTIBSFETUSJOHVUJMT w MJCTIBSFETBTUVUJMT NFUIPET SFHHFYQBUUFSOT
w MJCTPVSDFDPEFUPLFOTUPSFVUJMT the number of using methods
Knowledge 2: Node.js’s “util” module is useful
w VUJMJOTQFDU w VUJMGPSNBU w VUJMJOIFSJUT w VUJMMQSPNJTJGZ ˡ8IBUTVSQSJTFENFXBTUIJT Methods
used by ESLint
*NBHFCZIUUQTOPEFKTPSHBQJVUJMIUNM
Knowledge 3: Generator functions in JavaScript
Do you understand the following code?💁
None
Let's take a look at some sample codes💁
None
None
None
more detail, show MDN👉
An afterthought
An afterthought w /PUXSJUUFOJOUZQFTDSJQU UZQFEF fi OJUJPOTBSFXSJUUFO w "OZXBZ
UIFEPDVNFOUBUJPOJTFYUFOTJWF w +4%PDJTXFMMEPDVNFOUFE BTJTNE w %PDVNFOUBUJPOJTVTJOH&MFWFOUZKT UZ w 5PPMTGPS44( w %PDVNFOUBUJPOBQQJTFBTJFSUPWJFXUIBOUIFP ff i DJBMTJUF w 5IFSFBSFBMTPDPODFQUTPGMBZPVUBOEDPNQPOFOUT
None
None
Thoughts💁
Thoughts w 8FEPOUIBWFUPVOEFSTUBOEJUUPUBMZ👍 w %FTJHOJOHGBNPVTMJCSBSJFTJTBHSFBUMFBSOJOHFYQFSJFODF👍 w 8FDBOJNQSPWFNZTLJMMTGPSTVSF👍 w *GZPV fi
OEJUEJ ff i DVMU ZPVDBOSFBEJUXJUITPNFPOFFMTF👍 w *GZPVIBWFUSPVCMF JU`THPPEUPSFBEGSPNUIFUFTUDPEF👍
None