Learning Sessions: Refactoring Reminders

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Refactoring Reminders Don’t get lost in the trees Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Why Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Readability Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Communication Ideas (Business) Logic Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Maintainability Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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When Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Rule of Three “Two instances of the same code do not require refactoring - three, yes.” 1. When you’re doing something for the first time, just get it done. 2. When you’re doing something similar for the second time, cringe at having to repeat but do the same thing anyway. 3. When you’re doing something for the third time, start refactoring. Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Scout’s Rule “Always leave the campsite cleaner than when you found it.” Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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WRF Work > Right > Fast Make It Work, then Make It Right, then Make It Fast Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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How

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Code Smells (?)

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Code Smells - Bloaters Photo from refactoring.guru

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Code Smells - Abusers Photo from refactoring.guru

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Code Smells - Preventers Photo from refactoring.guru

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Code Smells - Dispensables Photo from refactoring.guru

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Code Smells - Couplers Photo from refactoring.guru

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But how many of these sound like judgement calls? Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Function Patterns Class Interaction Service Design Class Interaction Function Patterns Function Patterns Function Patterns Function Patterns Function Patterns science art Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Use Only What is Needed, Not More Less is More! Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Principle of Least Astonishment Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Be Idiomatic Make use of the tools you have Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Fail Loudly with trace Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Would I be able to understand this in one week, two months, three years? Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Delete Rename Move Oh! And prefer Renaming a file than Deleting and Adding. For it to appear as a rename in Git - rename the file in one commit, then modify in another if necessary. Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Start Small Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Communicate! Before, please Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Guiding Principles - No change in functionality - Tests continues passing and build is green - Can do/stop anytime (!) Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Principles > Practices Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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One More Thing Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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On nulls Let’s try to avoid them! - `null` should not be allowed as a valid input - There should be an explicit empty/base case for that. - Making variables non-nullable makes application behaviour predictable - `null` should only be allowed if we cannot help something to be null if things goes wrong As an Input: Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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On nulls [cont] - It’s the easy go-to for an empty object As an Output: Samantha Wong - Dashboard Learning Sessions - 20 May 2021

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Links References https://www.industriallogic.com/img/ blog/2005/09/smellstorefactorings.p df https://flylib.com/books/en/1.476.1/ https://refactoring.guru/

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CI/CD - Small, frequent changes -> lowering deployment risk - Build pipelines need to be well maintained - - Easy to find where are the mistakes

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End Samantha Wong - Dashboard Learning Sessions - 20 May 2021