Coding Standards and Best Practices

General

• Indentation should be consistent

  • I.e. all files should use either tabs or spaces and the same width (e.g. 4 characters)
  • Do not mix tabs and spaces

• Use one casing style

  • Usually:
    • camelCase for JavaScript
    • hyphen-case or camelCase for CSS
  • Do not mix casing styles e.g. let first_name = person.firstName;

• Test coverage should be sufficient

  • This should meet or exceed the configured threshold; if this isn't possible, explain why
• Comment code that might be difficult to understand...
  • ...but also consider simplifying complex code if at all possible. If you find that you're writing a lot of comments, then it's a good indicator that your code is too verbose and potentially overengineered

JavaScript

• Variable and function names should be descriptive

  • E.g. const actors = getActorsFromFilm(film); is easier to understand than const temp2 = doStuff(temp);

• Keep functions as short as possible

  • If a function is longer than 15 lines, consider breaking it down into smaller functions

• Use variables if a literal value is repeated more than once

  • E.g. console.log('Peter', 'Peter'.length); -> const name = 'Peter'; console.log(name, name.length);

CSS

• Styles should be based upon class selectors where possible e.g. .some-class

  • Facilitates reuse

• Don't use ID-based selectors e.g. #some-id

• Avoid styling HTML element selectors directly, unless it's to remove default browser styling

• Avoid using style properties in JavaScript

  • E.g. myElement.style.display = 'none';
  • This results in styles that are difficult to reuse
  • Use Element.prototype.classList instead e.g. myElement.classList.add('hidden');

Git

• Make small, frequent commits

  • If you make a mistake, then it's easier to revert than if you only make large, occasional commits

• Avoid committing commented-out code

  • If the code exists in a previous commit, then use GitHub or git diff to view it