Refactoring Golf

Instructions

npm install -g npm@latest

nvm install node

install yarn

https://classic.yarnpkg.com/lang/en/docs/install/#windows-stable

then, run yarn to install all dependencies

yarn needs to read the package.json file to know the dependencies and the scripts definitions

THE FOLOWING COMMAND LINES must be typed in a terminal, at the folder PATH where there is the 'package.json' file

yarn install --ignore-engines

Execute tests

Just run the test suite

yarn test

Run the test suit with code coverage

yarn test:ci

Game

• Start on hole 1 and refactor the code to be like the code in hole 2
  • Use a diff tool to see the differences in code between the starting hole and end hole
• Move to hole 2 and refactor the code from hole 2 to be like the code in hole 3
• Apply the same pattern until you reach hole 13
• Remember to keep the code compiling and the tests passing at all times during the refactor
• For every refactor, run the tests, and if they pass, commit
• It's okay, and actually heavily encouraged, to revert back to a previous working state at any moment
• Give each hole at least 3 attempts for each run.

Before you start

• Make sure you have identified as many code smells on the starting hole as possible.
• Make sure the code builds, and tests are passing yarn test

First run

• Refactor the code as best as you can.
  • Create your own branch based on 'hole001', for example: 'hole001-review'
    • Create a pull request
    • annotate your ideas, remarks on code
    • do the refactoring
    • create a Pull Request

Second run

• Refactor the code following the treatment available for each code smell in https://refactoring.guru/refactoring/smells.
  • Using pen and pencil, take note of the following:
    • For every compilation error you get during or after a refactor, count 1 strike.
    • For every failing test during or after a refactor, count 2 strikes.

Third run

• Refactor the code following the treatment available for each code smell in https://refactoring.guru/refactoring/smells. Use automated IDE refactoring as much as possible.
  • Using pen and pencil, take note of the following:
    • For every manual edit, count 1 strike.
      • Any code formatting applied does not count as a manual edit
      • Deleting blank lines or blank spaces does not count as a manual edit
    • For every compilation error you get during or after a refactor, count 1 strike.
    • For every failing test during or after a refactor, count 2 strikes.

Refactoring Priority Premise

The kata uses the following order of code smells to refactor

• Refactor readability
  • Comments
  • Dead code
  • Magic strings and numbers
  • Scope (variables, blocks)
  • Clutter
  • Implicit knowledge
  • Naming
• Reduce complexity
  • Duplicated code
  • Long method
• Reorder responsibilities
  • Data class
  • Message chain
  • Feature Envy
  • Inappropriate Intimacy
  • Large class
• Refine abstractions
  • Long parameter list
  • Data clump
  • Primitive obsession
  • Middle man
• Refactor to design patterns
  • Switch statements
  • Strategy
  • State
  • Command
  • others
• Refactor to SOLID
  • Refused bequest
  • Divergent change
  • Shotgun surgery
  • Speculative generality
  • Parallel inheritance

Additional Instructions

Execute mutation tests

yarn mutants

Run the tests in watch mode

yarn watch

Explanations, References

https://blog.logrocket.com/using-prettier-eslint-automate-formatting-fixing-javascript/#differences-between-eslint-prettier

https://code.visualstudio.com/docs/remote/wsl-tutorial