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
2. @codeJENNerator About Me
3. @codeJENNerator About You
4. @codeJENNerator What is ?
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
6. @codeJENNerator
7. @codeJENNerator • codenarc.sourceforge.net
8. @codeJENNerator • codenarc.sourceforge.net • Latest Release: 1.4.0 on May 26, 2019
9. @codeJENNerator Why use Codenarc? • Improves readability • Saves time with code reviews • Code with fewer bugs • Help onboard new team members
10. @codeJENNerator Who needs Codenarc? • Interns/Junior Devs • Java Devs converting to Groovy • New Team Members • YOU!
11. @codeJENNerator Demo
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') }
13. @codeJENNerator Other Codenarc Plugins • IntelliJ (recently updated!!) • Eclipse • Grails 2.x Plugin • Maven • Hudson/Jenkins
14. @codeJENNerator Approaches
15. @codeJENNerator Approaches • Start with one project or team
16. @codeJENNerator Approaches • Start with one project or team • Turn on all rules
17. @codeJENNerator Approaches • Start with one project or team • Turn on all rules • Look at all of the violations
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
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
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
21. @codeJENNerator Approaches • Turn on all the rules • Set a violation limit and fail builds that add go above the limit
22. https://flic.kr/p/rmit9T
23. @codeJENNerator 1.0 (Sept 2017) • Updates several library versions • Updated Infrastructure • Lots of bug fixes
24. @codeJENNerator 1.3 (Jan 2019) • Lots of new Javadoc rules • Fixes for some of the problematic JUnit rules
25. @codeJENNerator 1.4 (May 26, 2019) • Enforcing Static Compilation • More Javadoc formatting rules
26. img src: https://flic.kr/p/rehEf5 I don’t like all of the Codenarc Rules!
27. @codeJENNerator Dry • DuplicateListLiteral • DuplicateMapLiteral • DuplicateNumberLiteral • DuplicateStringLiteral
28. @codeJENNerator JUnit Ruleset Doesn’t work well with Spock
29. @codeJENNerator No Def https://flic.kr/p/apRkJh
30. @codeJENNerator No Def • Great for Spring Boot and other Groovy only projects https://flic.kr/p/apRkJh
31. @codeJENNerator No Def • Great for Spring Boot and other Groovy only projects • Problematic with Grails https://flic.kr/p/apRkJh
32. @codeJENNerator Good in Theory
33. @codeJENNerator Good in Theory • Unnecessary Return
34. @codeJENNerator Good in Theory • Unnecessary Return • Line Length
35. @codeJENNerator Debatable
36. @codeJENNerator Debatable • Unnecessary Groovy String
37. @codeJENNerator Debatable • Unnecessary Groovy String • Unnecessary Getter
38. @codeJENNerator Debatable
39. @codeJENNerator Debatable • Misordered Static Imports
40. @codeJENNerator Debatable • Misordered Static Imports • No Wildcard Imports
41. @codeJENNerator WARNING! • Enhanced Ruleset does not work with the gradle codenarc plugin • https://objectpartners.com/2016/03/16/resolving- codenarc-compilation-warnings/
42. @codeJENNerator Demo
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)
 }
 }
 }
 }
 }
44. @codeJENNerator Adding Custom Rules to Your Project • Follow the Grails Guide! https://guides.grails.org/ grails-codenarc/guide/index.html
45. @codeJENNerator Conclusion
46. @codeJENNerator Read the docs for more on.. • Rule Specifics • Ant Task • Command Line
47. @codeJENNerator
48. @codeJENNerator • Subscribe to the mailing list: https://sourceforge.net/ p/codenarc/mailman
49. @codeJENNerator • Subscribe to the mailing list: https://sourceforge.net/ p/codenarc/mailman • Contribute on GitHub: https://github.com/codenarc/ codenarc
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
51. @codeJENNerator Questions? https://flic.kr/p/5DeuzB https://speakerdeck.com/jlstrater/codenarc-revisited-gr8conf-eu-2019