Codenarc Revisited GR8Conf EU 2019

When was the last time you looked at code quality? Do you have some old codenarc configuration with half(or more!) of the rules turned off because they were reporting false positives? Or maybe you have @SupressWarnings all over your code? Or perhaps you want to do something small like to enforce tabs vs spaces for all members of your team?

Codenarc is a static analysis tool for Groovy that enforces style, detects bad practices, and suggests improvements. If it has been awhile since you last looked at codenarc, there might be new rules or configuration options to get you back on the path to better code quality. This session will explore what is new with codenarc, options for specific groovy ecosystem projects such as grails, and walk through how to create custom rules for your own project.

Transcript

1. Codenarc Revisited
   Jenn Strater
   @codeJENNerator
   

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2. @codeJENNerator
   About Me
   

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3. @codeJENNerator
   About You
   

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4. @codeJENNerator
   What
   is ?
   

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5. @codeJENNerator
   “CodeNarc is a static analysis tool for Groovy
   source code, enabling monitoring and
   enforcement of many coding standards and best
   practices…
   CodeNarc is similar to popular static analysis
   tools such as PMD or Checkstyle. Unlike those
   tools which analyze Java code, CodeNarc
   analyzes Groovy code.”
   https://github.com/CodeNarc/CodeNarc
   

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6. @codeJENNerator
   

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7. @codeJENNerator
   • codenarc.sourceforge.net
   

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8. @codeJENNerator
   • codenarc.sourceforge.net
   • Latest Release: 1.4.0 on May 26, 2019
   

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9. @codeJENNerator
   Why use Codenarc?
   • Improves readability
   • Saves time with code reviews
   • Code with fewer bugs
   • Help onboard new team members
   

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10. @codeJENNerator
    Who needs Codenarc?
    • Interns/Junior Devs
    • Java Devs converting to Groovy
    • New Team Members
    • YOU!
    

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11. @codeJENNerator
    Demo
    

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12. @codeJENNerator
    Configure the Gradle
    Plugin
    plugins {
    id 'codenarc'
    }
    codenarc {
    toolVersion = '1.4'
    }
    codenarcMain {
    configFile file('config/codenarc/codenarc.groovy')
    }
    codenarcTest {
    configFile file('config/codenarc/codenarcTest.groovy')
    }
    

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13. @codeJENNerator
    Other Codenarc Plugins
    • IntelliJ (recently updated!!)
    • Eclipse
    • Grails 2.x Plugin
    • Maven
    • Hudson/Jenkins
    

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14. @codeJENNerator
    Approaches
    

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15. @codeJENNerator
    Approaches
    • Start with one project or team
    

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16. @codeJENNerator
    Approaches
    • Start with one project or team
    • Turn on all rules
    

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17. @codeJENNerator
    Approaches
    • Start with one project or team
    • Turn on all rules
    • Look at all of the violations
    

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18. @codeJENNerator
    Approaches
    • Start with one project or team
    • Turn on all rules
    • Look at all of the violations
    • Turn off rules that don’t make sense for your team
    

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19. @codeJENNerator
    Approaches
    • Start with one project or team
    • Turn on all rules
    • Look at all of the violations
    • Turn off rules that don’t make sense for your team
    • Fix all the problems
    

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20. @codeJENNerator
    Approaches
    • Start with one project or team
    • Turn on all rules
    • Look at all of the violations
    • Turn off rules that don’t make sense for your team
    • Fix all the problems
    • Once you have a good set of rules with minimal false
    positives, set that as the standard for all teams using
    Groovy
    

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21. @codeJENNerator
    Approaches
    • Turn on all the rules
    • Set a violation limit and fail builds that add go
    above the limit
    

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22. https://flic.kr/p/rmit9T
    

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23. @codeJENNerator
    1.0 (Sept 2017)
    • Updates several library versions
    • Updated Infrastructure
    • Lots of bug fixes
    

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24. @codeJENNerator
    1.3 (Jan 2019)
    • Lots of new Javadoc rules
    • Fixes for some of the problematic JUnit rules
    

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25. @codeJENNerator
    1.4 (May 26, 2019)
    • Enforcing Static Compilation
    • More Javadoc formatting rules
    

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26. img src: https://flic.kr/p/rehEf5
    I don’t like all of the Codenarc Rules!
    

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27. @codeJENNerator
    Dry
    • DuplicateListLiteral
    • DuplicateMapLiteral
    • DuplicateNumberLiteral
    • DuplicateStringLiteral
    

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28. @codeJENNerator
    JUnit Ruleset
    Doesn’t work well with Spock
    

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29. @codeJENNerator
    No Def
    https://flic.kr/p/apRkJh
    

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30. @codeJENNerator
    No Def
    • Great for Spring Boot and other
    Groovy only projects
    https://flic.kr/p/apRkJh
    

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31. @codeJENNerator
    No Def
    • Great for Spring Boot and other
    Groovy only projects
    • Problematic with Grails
    https://flic.kr/p/apRkJh
    

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32. @codeJENNerator
    Good in Theory
    

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33. @codeJENNerator
    Good in Theory
    • Unnecessary Return
    

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34. @codeJENNerator
    Good in Theory
    • Unnecessary Return
    • Line Length
    

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35. @codeJENNerator
    Debatable
    

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36. @codeJENNerator
    Debatable
    • Unnecessary Groovy String
    

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37. @codeJENNerator
    Debatable
    • Unnecessary Groovy String
    • Unnecessary Getter
    

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38. @codeJENNerator
    Debatable
    

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39. @codeJENNerator
    Debatable
    • Misordered Static Imports
    

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40. @codeJENNerator
    Debatable
    • Misordered Static Imports
    • No Wildcard Imports
    

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41. @codeJENNerator
    WARNING!
    • Enhanced Ruleset does not work with the gradle
    codenarc plugin
    • https://objectpartners.com/2016/03/16/resolving-
    codenarc-compilation-warnings/
    

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42. @codeJENNerator
    Demo
    

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43. @codeJENNerator
    Create a Custom Rule
    import org.codenarc.rule.AbstractRule

    import org.codenarc.source.SourceCode

    

    /**

    * Sample rule. Checks for static fields.

    */

    class MyStaticFieldRule extends AbstractRule {

    String name = 'MyStaticField'

    int priority = 2

    

    void applyTo(SourceCode sourceCode, List violations) {

    sourceCode.ast.classes.each { clazz ->

    clazz.fields.each { fieldNode ->

    if (fieldNode.static) {

    violations << createViolation(sourceCode, fieldNode)

    }

    }

    }

    }

    }
    

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44. @codeJENNerator
    Adding Custom Rules to
    Your Project
    • Follow the Grails Guide! https://guides.grails.org/
    grails-codenarc/guide/index.html
    

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45. @codeJENNerator
    Conclusion
    

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46. @codeJENNerator
    Read the docs for more
    on..
    • Rule Specifics
    • Ant Task
    • Command Line
    

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47. @codeJENNerator
    

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48. @codeJENNerator
    • Subscribe to the mailing list: https://sourceforge.net/
    p/codenarc/mailman
    

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49. @codeJENNerator
    • Subscribe to the mailing list: https://sourceforge.net/
    p/codenarc/mailman
    • Contribute on GitHub: https://github.com/codenarc/
    codenarc
    

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50. @codeJENNerator
    Example Rulesets
    • Grails
    • https://github.com/jlstrater/gr8data/tree/master/
    config/codenarc
    • Spring Boot
    • https://github.com/jlstrater/groovy-spring-boot-
    restdocs-example/tree/master/gradle/codenarc
    

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51. @codeJENNerator
    Questions?
    https://flic.kr/p/5DeuzB
    https://speakerdeck.com/jlstrater/codenarc-revisited-gr8conf-eu-2019
    

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