What I Talk About When I Talk About Ktlint

5min. LT @ shibuya.apk #23
ktlint
https://github.com/shyiko/ktlint

Lint for Kotlin
https://speakerdeck.com/takusemba/lint-for-kotlin

kotlinとLintとEditorConfig
https://qiita.com/kaelaela/items/508632fd26fdb553dc89

Transcript

1. What
   I talk
   about
   when I
   talk
   about
   Ktlint
   kaelaela
   

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2. Problems in a large team
   ● Spawn untold coding rule
   ● Reviewer spend fluitless time for similer
   mistake
   ● Yesterday’s nice doc could be today’s trash
   

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3. Difficulty of Kotlin
   ● Many different ways of writing
   ● So we make many team rules
   ● These all rules can’t taught through word of
   mouth
   

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4. We have many solutions
   ● Inspect by Android Studio
   ● Static code analytics
   ● Automate with Danger
   etc...
   

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5. Static code analytics
   e.g.
   FindBugs
   Android Lint
   Ktlint
   ...
   

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6. What is ktlint？
   

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7. Customize with editorconfig
   

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8. Basic usage
   Write code Push CI Analytics + Danger Fix format Push Review Fix Push
   

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9. Not good enough
   Write code Push CI Analytics + Danger Fix format Push Review Fix Push
   we S I L ne fi d o r d .
   

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10. Redundant commits...
    ● fix danger comment
    ● fix danger
    ● fix code format
    ● format code
    ● format
    ● :put_litter_in_its_place:
    ...
    

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11. Write code Push CI Analytics + Danger Fix format Push Review Fix Push
    More and more automation
    

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12. Write code build & format push CI Analytics + Danger Review Fix Push
    More and more automation
    

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13. Write code build & format push CI Analytics + Danger Review Fix Push
    More and more automation
    No m ed n ev .
    No m or c it.
    No m or c e r a d!
    

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14. Add ktformat task to build.gradle
    task ktFormat {
    description "R.I.P danger..."
    classpath = configrations.ktlint
    Main = "com.github.shyiko.ktlint.Main"
    args "-F", "src/**/*.kt"
    }
    

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15. Add ktformat task to build.gradle
    task ktFormat {
    description "R.I.P danger..."
    classpath = configrations.ktlint
    Main = "com.github.shyiko.ktlint.Main"
    args "-F", "src/**/*.kt"
    } For p i
    

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16. Add ktformat task to build.gradle
    task ktFormat {
    description "R.I.P danger..."
    classpath = configrations.ktlint
    Main = "com.github.shyiko.ktlint.Main"
    args "-F", "src/**/*.kt"
    } Yo c ha t et s
    

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17. Only format @ local debug build time
    e.g.
    applicationVariants.all { variant ->
    def flavor = variant.productFlavors[0].name
    def buildType = variant.buildType.name
    if (flavor == 'develop' && buildType == 'debug') {
    ktFormat.execute()
    }
    }
    

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18. $./gradlew --profile ktFormat
    Che p r a c
    on p o c !
    

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19. What I talk about
    ● Use ktlint for your team
    ● Do not review about code fomat
    ● And I want to remove “Format commit”
    ● Use ktFormat for reviewer and you
    ● Format at local debug build time
    ● Focus your coding
    

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20. Tha y .
    What
    I talk
    about
    when I
    talk
    about
    Ktlint
    

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