How static PHP analyzer changed the way I look at code

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How static PHP analyzer changed the way I look at code Nicole Cordes, biz-design, SymfonyCon Lisbon 2018

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TOOLS

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TOOLS PHPStan PHP Static Analysis Tool  https://github.com/phpstan/phpstan Strength: Type safety checks

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TOOLS PHPStan PHP Static Analysis Tool  https://github.com/phpstan/phpstan Strength: Type safety checks

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TOOLS PHPMD PHP Mess Detector  https://phpmd.org Strength: Code structure and measurements

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TOOLS PHPMD PHP Mess Detector  https://phpmd.org Strength: Code structure and measurements

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TOOLS Code Climate Automated code review and quality analytics  https://codeclimate.com Strength: Lines of code and complexity

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TOOLS Code Climate Automated code review and quality analytics  https://codeclimate.com Strength: Lines of code and complexity

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TOOLS Code Climate Automated code review and quality analytics  https://codeclimate.com Strength: Lines of code and complexity

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TOOLS SonarCloud SonarQube as a Service  https://sonarcloud.io Strength: Code complexity and duplications

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TOOLS SonarCloud SonarQube as a Service  https://sonarcloud.io Strength: Code complexity and duplications

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TOOLS SonarCloud SonarQube as a Service  https://sonarcloud.io Strength: Code complexity and duplications

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TOOLS SonarCloud SonarQube as a Service  https://sonarcloud.io Strength: Code complexity and duplications

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MEASUREMENT

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MEASUREMENT Names  Variable names  Not too short  Not too long  lowerCamelCase  Method names  Not too short  Usage of __construct method  isX() or hasY() for bool return type

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MEASUREMENT Lengths  Method size too long  Split into multiple small pieces  Parameter list too long  Group parameters in new objects  (Public) field count to high  Redesign objects and group fields

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CODE

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CODE Structure I  Commented out code  Remove!  Too many return statements  Return early but only once  Prevent superfluous return variables  Prevent superfluous else branch  Too many return type possibilities  Stick to one return type

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CODE Structure II  Too many methods  Split into multiple object  Throw dedicated exceptions  Avoid static calls  Use dependencies

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COMPLEXITY

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COMPLEXITY Cognitive Complexity  How hard is your code to understand  Each control structure increases the complexity  Logical operators increase the count  Ternary and null coalescing operator increase the count  Merge nested if statements  Refactor and use helper functions

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CONCLUSION

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CONCLUSION The way I changed  I pay more attention in naming variables and methods  I refractor conditions to own functions  I prevent multiple return points  I use exactly one return type  I started to think about my code before I write it  Benefits  My classes and concepts are more structured  My code is more readable  My code is better testable

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WARNING

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WARNING Stop overengineering  Maybe not possible to remove all remarks  Depending on frameworks  Depending on time  Depending on money  False positives may be found  Use the knowledge in upcoming code!

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Thank you for listening

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Photograph Credits  https://pxhere.com/en/photo/868966  https://pxhere.com/en/photo/599783  https://pxhere.com/en/photo/46962  https://commons.wikimedia.org/wiki/File:Jenga_distorted.jpg  https://pxhere.com/en/photo/1175794  https://pxhere.com/en/photo/672522