Clean Code: A Handbook of Agile Software Craftsmanship, 2nd Edition

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Relentless Improvement

5. I will fearlessly and relentlessly improve my creations at every opportunity. I will never degrade them.

Robert Baden Powell, the father of the Boy Scouts of America, left a posthumous message exhorting the scouts to leave the world a better place than they found it. It was from this statement that the “Boy Scout Rule” was derived.

Check the code in cleaner than you checked it out.

How? By performing random acts of kindness upon the code every time you check it in. One of those random acts of kindness is to increase test coverage.

Test Coverage

Do you measure how much of your code is covered by your tests? Do you know what percentage of lines are covered? Do you know what percentage of branches are covered? If not, ...